As in Brazil, the mandolin has played an important role in the Music of Venezuela. It has enjoyed a privileged position as the main melodic instrument in several different regions of the country. Specifically, the eastern states of Sucre, Nueva Esparta, Anzoategui and Monagas have made the mandolin the main instrument in their versions of Joropo as well as Puntos, Jotas, Polos, Fulias, Merengues and Malagueñas. Also, in the west of the country the sound of the mandolin is intrinsically associated with the regional genres of the Venezuelan Andes: Bambucos, Pasillos, Pasodobles, and Waltzes. In the western city of Maracaibo the Mandolin has been played in Decimas, Danzas and Contradanzas Zulianas; in the capital, Caracas, the Merengue Rucaneao, Pasodobles and Waltzes have also been played with mandolin for almost a century. Today, Venezuelan mandolists include an important group of virtuoso players and ensembles such as Alberto Valderrama, Jesus Rengel, Ricardo Sandoval, Saul Vera, and Cristobal Soto.

What place in Brazil do mandolins play an important role?

Venezuela

What is the sound of mandolin associated with in the west country?

regional genres of the Venezuelan Andes

Who are the famous Venezuelen mandolinist?

Alberto Valderrama, Jesus Rengel, Ricardo Sandoval, Saul Vera, and Cristobal Soto.

What place in Brazil do mandolins play an unimportant role?

I'm not sure.

What is the sound of mandolin not associated with in the west country?

I'm not sure.

Who are the not famous Venezuelen mandolinist?

I'm not sure.


To fill this gap in the literature, mandolin orchestras have traditionally played many arrangements of music written for regular orchestras or other ensembles. Some players have sought out contemporary composers to solicit new works. Traditional mandolin orchestras remain especially popular in Japan and Germany, but also exist throughout the United States, Europe and the rest of the world. They perform works composed for mandolin family instruments, or re-orchestrations of traditional pieces. The structure of a contemporary traditional mandolin orchestra consists of: first and second mandolins, mandolas (either octave mandolas, tuned an octave below the mandolin, or tenor mandolas, tuned like the viola), mandocellos (tuned like the cello), and bass instruments (conventional string bass or, rarely, mandobasses). Smaller ensembles, such as quartets composed of two mandolins, mandola, and mandocello, may also be found.

What type of music has mandolins played?

mandolin orchestras have traditionally played many arrangements of music written for regular orchestras or other ensembles

Where do traditional mandolin orchestras remain popular?

Japan and Germany

What do the structure of a contempory traditional orchestra consist of?

first and second mandolins,

What are smalled ensambles composed of?

two mandolins, mandola, and mandocello,

What are the mandocellos usually tuned like?

cello

What type of music has mandolins never played?

I'm not sure.

Where do traditional mandolin orchestras remain unpopular?

I'm not sure.

What do the structure of a contemporary untraditional orchestra consist of?

I'm not sure.

What are large ensambles composed of?

I'm not sure.


Insects (from Latin insectum, a calque of Greek ἔντομον [éntomon], "cut into sections") are a class of invertebrates within the arthropod phylum that have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs of jointed legs, compound eyes and one pair of antennae. They are the most diverse group of animals on the planet, including more than a million described species and representing more than half of all known living organisms. The number of extant species is estimated at between six and ten million, and potentially represent over 90% of the differing animal life forms on Earth. Insects may be found in nearly all environments, although only a small number of species reside in the oceans, a habitat dominated by another arthropod group, crustaceans.

In what phylum are insects classified?

arthropod

How many parts comprise the body of an insect?

three-part

In addition to the head and abdomen, what is the other major section of an insect's body?

thorax

What type of exoskeleton do insects have?

chitinous

How many pairs of jointed legs do insects have?

three

What does insect mean in latin?

cut into sections

What is the Latin word for insect?

insectum

Insects are a class of what?

invertebrates

Insects have what kind of skeleton?

chitinous exoskeleton

An insects 3-part body includes a throat, abdomen, and what?

head


The life cycles of insects vary but most hatch from eggs. Insect growth is constrained by the inelastic exoskeleton and development involves a series of molts. The immature stages can differ from the adults in structure, habit and habitat, and can include a passive pupal stage in those groups that undergo 4-stage metamorphosis (see holometabolism). Insects that undergo 3-stage metamorphosis lack a pupal stage and adults develop through a series of nymphal stages. The higher level relationship of the Hexapoda is unclear. Fossilized insects of enormous size have been found from the Paleozoic Era, including giant dragonflies with wingspans of 55 to 70 cm (22–28 in). The most diverse insect groups appear to have coevolved with flowering plants.

How does the lifecycle of most insects typically begin?

hatch from eggs

What is the primary constraint on the physical growth of an insect?

inelastic exoskeleton

What stage of development differentiates a 4-stage metamorphosis from a 3-stage metamorphosis, notably absent in the latter?

pupal stage

What is the term given to denote the series of stages involved in the development of an adult insect?

nymphal

What era is attributed to the findings of enormous fossilized dragonflies with extremely long wingspans?

Paleozoic

Insects hatch from what?

eggs

Insects growth is constrained by what?

the inelastic exoskeleton

An insects developement involves a series of what?

molts

How many stages of metamorphosis does an insect go through?

The most diverse insects coevolved with what?

flowering plants


Adult insects typically move about by walking, flying, or sometimes swimming (see below, Locomotion). As it allows for rapid yet stable movement, many insects adopt a tripedal gait in which they walk with their legs touching the ground in alternating triangles. Insects are the only invertebrates to have evolved flight. Many insects spend at least part of their lives under water, with larval adaptations that include gills, and some adult insects are aquatic and have adaptations for swimming. Some species, such as water striders, are capable of walking on the surface of water. Insects are mostly solitary, but some, such as certain bees, ants and termites, are social and live in large, well-organized colonies. Some insects, such as earwigs, show maternal care, guarding their eggs and young. Insects can communicate with each other in a variety of ways. Male moths can sense the pheromones of female moths over great distances. Other species communicate with sounds: crickets stridulate, or rub their wings together, to attract a mate and repel other males. Lampyridae in the beetle order Coleoptera communicate with light.

What is the term for the gait of an insect characterized by walking in alternating triangles?

tripedal

What larval adaptation is common to underwater insects?

gills

What species of insect has the capability to walk on the surface of water?

water striders

What do crickets do in order to attract or repel a mate?

stridulate

What variation of beetle in the Coleoptera order communicate by way of light?

Lampyridae

Insects move by walking, flying, and what else?

swimming

Which insects walk, fly, and swim?

Adult

Insects walk the ground in alternating what?

triangles

Insects walking in an alternating triangle is called a what?

tripedal gait

What can insects do with each other in a variety of ways?

communicate


Humans regard certain insects as pests, and attempt to control them using insecticides and a host of other techniques. Some insects damage crops by feeding on sap, leaves or fruits. A few parasitic species are pathogenic. Some insects perform complex ecological roles; blow-flies, for example, help consume carrion but also spread diseases. Insect pollinators are essential to the life-cycle of many flowering plant species on which most organisms, including humans, are at least partly dependent; without them, the terrestrial portion of the biosphere (including humans) would be devastated. Many other insects are considered ecologically beneficial as predators and a few provide direct economic benefit. Silkworms and bees have been used extensively by humans for the production of silk and honey, respectively. In some cultures, people eat the larvae or adults of certain insects.

By what method do humans often try to control the spread of insects?

insecticides

What portion of the biosphere would be devastated absent the complex pollination role of insects?

terrestrial

What insect provides a tangible economic benefit via the production of silk?

Silkworms

What insect is known to consume carrion?

blow-flies

Humans consider most insects as what?

pests

Humans can control insects using what?

insecticides

Insects have the potential to damage what?

crops

Insects can damage crops by feeing on sap, fruits, or what?

leaves

Silkworms are used by humans for producing what?

silk


The word "insect" comes from the Latin word insectum, meaning "with a notched or divided body", or literally "cut into", from the neuter singular perfect passive participle of insectare, "to cut into, to cut up", from in- "into" and secare "to cut"; because insects appear "cut into" three sections. Pliny the Elder introduced the Latin designation as a loan-translation of the Greek word ἔντομος (éntomos) or "insect" (as in entomology), which was Aristotle's term for this class of life, also in reference to their "notched" bodies. "Insect" first appears documented in English in 1601 in Holland's translation of Pliny. Translations of Aristotle's term also form the usual word for "insect" in Welsh (trychfil, from trychu "to cut" and mil, "animal"), Serbo-Croatian (zareznik, from rezati, "to cut"), Russian (насекомое nasekomoje, from seč'/-sekat', "to cut"), etc.

What is the Latin term for insect?

insectum

Who introduced the Latin term for insect, borrowing from the Greek vernacular?

Pliny the Elder

How many sections does an insect's body appear to be divided?

three

Which Greek philosopher used the term entomos to describe insects, making reference to their notched bodies?

Aristotle

In what year is it typically reported that the word insect was first documented in English?

Insect means to have a notched or divided what?

body

Insects are cut into how many sections?

three sections

Who gave this class of life the name "insect"?

Aristotle

In what year did the word "insect" appear in a document?

Who introduced the Latin version of the word "insect"?

Pliny the Elder


The higher-level phylogeny of the arthropods continues to be a matter of debate and research. In 2008, researchers at Tufts University uncovered what they believe is the world's oldest known full-body impression of a primitive flying insect, a 300 million-year-old specimen from the Carboniferous period. The oldest definitive insect fossil is the Devonian Rhyniognatha hirsti, from the 396-million-year-old Rhynie chert. It may have superficially resembled a modern-day silverfish insect. This species already possessed dicondylic mandibles (two articulations in the mandible), a feature associated with winged insects, suggesting that wings may already have evolved at this time. Thus, the first insects probably appeared earlier, in the Silurian period.

From what period do researchers believe that the oldest known full-body impression of a flying insect originates?

Carboniferous

What is believed to be the oldest known insect fossil?

Devonian Rhyniognatha hirsti

In what year did Tufts researchers reportedly uncover what is believed to be the oldest known impression of a flying insect?

What is the term for a mandible with two articulations?

dicondylic

With what type of insect is a dicondylic mandible associated?

winged

What higher-level is constantly up for debate and research?

phylogeny

The higher-level phylogeny is of the what?

arthropods

What kind of impression has been uncovered by a University?

full-body

A University discovered a primitive flying what?

insect

How old is the primitive plying insect found by the University?

300 million-year-old


Late Carboniferous and Early Permian insect orders include both extant groups, their stem groups, and a number of Paleozoic groups, now extinct. During this era, some giant dragonfly-like forms reached wingspans of 55 to 70 cm (22 to 28 in), making them far larger than any living insect. This gigantism may have been due to higher atmospheric oxygen levels that allowed increased respiratory efficiency relative to today. The lack of flying vertebrates could have been another factor. Most extinct orders of insects developed during the Permian period that began around 270 million years ago. Many of the early groups became extinct during the Permian-Triassic extinction event, the largest mass extinction in the history of the Earth, around 252 million years ago.

In addition to Carboniferous, what other insect order is inclusive of extant groups, stem groups and Paleozoic groups?

Early Permian

To what measurement, in cm, did the wingspans of giant dragonfly-like forms reach?

55 to 70

Higher levels of what substance possibly contributed to the phenomenon of gigantism?

oxygen

How many million years ago is the Permian period believed to have begun?

The most significant mass extinction of insect groups is commonly ascribed to what period?

Permian-Triassic

Late Caboniferous and Early Permain are what kind of orders?

insect orders

The insect orders include both of what?

extant groups

The insect orders include a number of what kind of groups?

Paleozoic groups

What kind of giant insect form had wingspans?

dragonfly-like forms

How wide were the wingspans of the dragonfly-like forms?

55 to 70 cm


Insects were among the earliest terrestrial herbivores and acted as major selection agents on plants. Plants evolved chemical defenses against this herbivory and the insects, in turn, evolved mechanisms to deal with plant toxins. Many insects make use of these toxins to protect themselves from their predators. Such insects often advertise their toxicity using warning colors. This successful evolutionary pattern has also been used by mimics. Over time, this has led to complex groups of coevolved species. Conversely, some interactions between plants and insects, like pollination, are beneficial to both organisms. Coevolution has led to the development of very specific mutualisms in such systems.

What type of defense did plants adaptively evolve in response to insects?

chemical

What is the term for a plant-eating insect?

herbivores

What do many insects adaptively utilize in self-defense from predators?

plant toxins

How is toxicity sometimes visibly displayed by insects as a warning?

colors

What is an example of a mutually beneficial process indicating the coevolution of plants and insects?

pollination

Insects are considered terrestrial what?

herbivores

What were insects the major selection agents of?

plants

What did plants eventually form against insects?

chemical defenses

Insects formed mechanisms to shield against what?

plant toxins

Insects show how toxic they are with what kind of colors?

warning colors


Insects can be divided into two groups historically treated as subclasses: wingless insects, known as Apterygota, and winged insects, known as Pterygota. The Apterygota consist of the primitively wingless order of the silverfish (Thysanura). Archaeognatha make up the Monocondylia based on the shape of their mandibles, while Thysanura and Pterygota are grouped together as Dicondylia. The Thysanura themselves possibly are not monophyletic, with the family Lepidotrichidae being a sister group to the Dicondylia (Pterygota and the remaining Thysanura).

What is the term for the class of insects with wings?

Pterygota

What is the term for the class of insects without wings?

Apterygota

What group of insects are inclusive within the Monocondylia primarily due to the shape of their mandible?

Archaeognatha

What is the collective group to which Thysanura and Pterygota belong?

Dicondylia

Insects are historically divided into how many groups?

two groups

Insects with wings are known as what?

Pterygota

Does an Apterygots have wings or wingless?

wingless

What is a Thysanura?

silverfish

Thysanura and Pterygota are what?

Dicondylia


Traditional morphology-based or appearance-based systematics have usually given the Hexapoda the rank of superclass,:180 and identified four groups within it: insects (Ectognatha), springtails (Collembola), Protura, and Diplura, the latter three being grouped together as the Entognatha on the basis of internalized mouth parts. Supraordinal relationships have undergone numerous changes with the advent of methods based on evolutionary history and genetic data. A recent theory is that the Hexapoda are polyphyletic (where the last common ancestor was not a member of the group), with the entognath classes having separate evolutionary histories from the Insecta. Many of the traditional appearance-based taxa have been shown to be paraphyletic, so rather than using ranks like subclass, superorder, and infraorder, it has proved better to use monophyletic groupings (in which the last common ancestor is a member of the group). The following represents the best-supported monophyletic groupings for the Insecta.

Morphology-based and appearance-based are known as what?

systematics

What class is the Hexapoda ranked?

superclass

How many groups are defined in the superclass?

four groups

Springtails are also known as what?

Collembola

Collembola, protura, and dipkura are in a group called what?

Entognatha


Paleoptera and Neoptera are the winged orders of insects differentiated by the presence of hardened body parts called sclerites, and in the Neoptera, muscles that allow their wings to fold flatly over the abdomen. Neoptera can further be divided into incomplete metamorphosis-based (Polyneoptera and Paraneoptera) and complete metamorphosis-based groups. It has proved difficult to clarify the relationships between the orders in Polyneoptera because of constant new findings calling for revision of the taxa. For example, the Paraneoptera have turned out to be more closely related to the Endopterygota than to the rest of the Exopterygota. The recent molecular finding that the traditional louse orders Mallophaga and Anoplura are derived from within Psocoptera has led to the new taxon Psocodea. Phasmatodea and Embiidina have been suggested to form the Eukinolabia. Mantodea, Blattodea, and Isoptera are thought to form a monophyletic group termed Dictyoptera.

Paleoptera and Neoptera are what kind of insect orders?

winged

An insects hard body parts are called what?

sclerites

Insect's wings fold flat over their what?

abdomen

Neoptera can be divided into what kind of "based" group?

metamorphosis-based

Paraneopter and Endopterygota are closely what?

related


The Exopterygota likely are paraphyletic in regard to the Endopterygota. Matters that have incurred controversy include Strepsiptera and Diptera grouped together as Halteria based on a reduction of one of the wing pairs – a position not well-supported in the entomological community. The Neuropterida are often lumped or split on the whims of the taxonomist. Fleas are now thought to be closely related to boreid mecopterans. Many questions remain in the basal relationships amongst endopterygote orders, particularly the Hymenoptera.

What are likely to be paraphyletic?

The Exopterygota

Strepsiptera and Diptera are controversial what?

Matters

Strepsiptera and Diptera grouped together are called what?

Halteria

A discussion regarding wing pairs is not supported by what community?

the entomological community

What is split or lumped together by a taxonomist?

The Neuropterida


Though the true dimensions of species diversity remain uncertain, estimates range from 2.6–7.8 million species with a mean of 5.5 million. This probably represents less than 20% of all species on Earth[citation needed], and with only about 20,000 new species of all organisms being described each year, most species likely will remain undescribed for many years unless species descriptions increase in rate. About 850,000–1,000,000 of all described species are insects. Of the 24 orders of insects, four dominate in terms of numbers of described species, with at least 3 million species included in Coleoptera, Diptera, Hymenoptera and Lepidoptera. A recent study estimated the number of beetles at 0.9–2.1 million with a mean of 1.5 million.

The true diversity within the insect species remains what?

uncertain

How many insect species are estimated to exist?

2.6–7.8 million species

How many new species of all organisms are discovered each year?

Of all the species on earth, how much do insects make up?

less than 20%

For many years to come, most insect species will remain as what?

undescribed


Insects have segmented bodies supported by exoskeletons, the hard outer covering made mostly of chitin. The segments of the body are organized into three distinctive but interconnected units, or tagmata: a head, a thorax and an abdomen. The head supports a pair of sensory antennae, a pair of compound eyes, and, if present, one to three simple eyes (or ocelli) and three sets of variously modified appendages that form the mouthparts. The thorax has six segmented legs—one pair each for the prothorax, mesothorax and the metathorax segments making up the thorax—and, none, two or four wings. The abdomen consists of eleven segments, though in a few species of insects, these segments may be fused together or reduced in size. The abdomen also contains most of the digestive, respiratory, excretory and reproductive internal structures.:22–48 Considerable variation and many adaptations in the body parts of insects occur, especially wings, legs, antenna and mouthparts.

What kind of bodies to insects have?

segmented bodies

Insects bodies are supported by what?

exoskeletons

Chitin is what kind of outer covering on an insect?

hard

An insect's body is divided into what kind of units?

interconnected

What is an insects head, throat, and abdomen called?

tagmata


The head is enclosed in a hard, heavily sclerotized, unsegmented, exoskeletal head capsule, or epicranium, which contains most of the sensing organs, including the antennae, ocellus or eyes, and the mouthparts. Of all the insect orders, Orthoptera displays the most features found in other insects, including the sutures and sclerites. Here, the vertex, or the apex (dorsal region), is situated between the compound eyes for insects with a hypognathous and opisthognathous head. In prognathous insects, the vertex is not found between the compound eyes, but rather, where the ocelli are normally. This is because the primary axis of the head is rotated 90° to become parallel to the primary axis of the body. In some species, this region is modified and assumes a different name.:13

What part of the insect contains most of the sensing organs?

head

What is another word for head capsule?

epicranium

What displays the most features on an insect?

Orthoptera

What is the vertex also known as?

apex

The vertex is usually located between what kind of eyes?

compound


The thorax is a tagma composed of three sections, the prothorax, mesothorax and the metathorax. The anterior segment, closest to the head, is the prothorax, with the major features being the first pair of legs and the pronotum. The middle segment is the mesothorax, with the major features being the second pair of legs and the anterior wings. The third and most posterior segment, abutting the abdomen, is the metathorax, which features the third pair of legs and the posterior wings. Each segment is dilineated by an intersegmental suture. Each segment has four basic regions. The dorsal surface is called the tergum (or notum) to distinguish it from the abdominal terga. The two lateral regions are called the pleura (singular: pleuron) and the ventral aspect is called the sternum. In turn, the notum of the prothorax is called the pronotum, the notum for the mesothorax is called the mesonotum and the notum for the metathorax is called the metanotum. Continuing with this logic, the mesopleura and metapleura, as well as the mesosternum and metasternum, are used.

The throax has how many sections?

three sections

Another term for tagma is?

thorax

The anterior section is closest to the what?

head

The prothrorax is what segment of the insect?

anterior

The pleura is made of how many lateral regions?

two


The abdomen is the largest tagma of the insect, which typically consists of 11–12 segments and is less strongly sclerotized than the head or thorax. Each segment of the abdomen is represented by a sclerotized tergum and sternum. Terga are separated from each other and from the adjacent sterna or pleura by membranes. Spiracles are located in the pleural area. Variation of this ground plan includes the fusion of terga or terga and sterna to form continuous dorsal or ventral shields or a conical tube. Some insects bear a sclerite in the pleural area called a laterotergite. Ventral sclerites are sometimes called laterosternites. During the embryonic stage of many insects and the postembryonic stage of primitive insects, 11 abdominal segments are present. In modern insects there is a tendency toward reduction in the number of the abdominal segments, but the primitive number of 11 is maintained during embryogenesis. Variation in abdominal segment number is considerable. If the Apterygota are considered to be indicative of the ground plan for pterygotes, confusion reigns: adult Protura have 12 segments, Collembola have 6. The orthopteran family Acrididae has 11 segments, and a fossil specimen of Zoraptera has a 10-segmented abdomen.

What is the largest tagma of an insect?

abdomen

How many segments make up an insects abdomen?

11–12 segments

The abdomen is less strong than the thorax and what?

head

An insects abdomen has a sclerotized tergum and what else?

sternum

The pleural area holds what?

Spiracles


The insect outer skeleton, the cuticle, is made up of two layers: the epicuticle, which is a thin and waxy water resistant outer layer and contains no chitin, and a lower layer called the procuticle. The procuticle is chitinous and much thicker than the epicuticle and has two layers: an outer layer known as the exocuticle and an inner layer known as the endocuticle. The tough and flexible endocuticle is built from numerous layers of fibrous chitin and proteins, criss-crossing each other in a sandwich pattern, while the exocuticle is rigid and hardened.:22–24 The exocuticle is greatly reduced in many soft-bodied insects (e.g., caterpillars), especially during their larval stages.

Insect's outer skeleton is known as what?

the cuticle

The cuticle has how many layers?

two

Which cuticle later is like wax?

the epicuticle

The epicuticle does not consist of what?

chitin

Is the procuticle thinner or thicker than the epicuticle?

thicker


Insects are the only invertebrates to have developed active flight capability, and this has played an important role in their success.:186 Their muscles are able to contract multiple times for each single nerve impulse, allowing the wings to beat faster than would ordinarily be possible. Having their muscles attached to their exoskeletons is more efficient and allows more muscle connections; crustaceans also use the same method, though all spiders use hydraulic pressure to extend their legs, a system inherited from their pre-arthropod ancestors. Unlike insects, though, most aquatic crustaceans are biomineralized with calcium carbonate extracted from the water.

Insects are also known as what kind of vertebra?

invertebrates

Insects have developed what kind of active capability?

flight

Active flight ability has played what kind of role for insects?

important

How many times are insects muscles able to contract?

multiple

Insects muscles are attached to their what?

exoskeletons


The thoracic segments have one ganglion on each side, which are connected into a pair, one pair per segment. This arrangement is also seen in the abdomen but only in the first eight segments. Many species of insects have reduced numbers of ganglia due to fusion or reduction. Some cockroaches have just six ganglia in the abdomen, whereas the wasp Vespa crabro has only two in the thorax and three in the abdomen. Some insects, like the house fly Musca domestica, have all the body ganglia fused into a single large thoracic ganglion.

What is on each side of a thoracic segment?

ganglion

How many ganglia are on each side of a thoracic segment?

one

Ganglia are connected into a what?

a pair

How many pairs of ganglia are in a segment?

one pair

What other location on an insect are ganglia located?

abdomen


At least a few insects have nociceptors, cells that detect and transmit sensations of pain. This was discovered in 2003 by studying the variation in reactions of larvae of the common fruitfly Drosophila to the touch of a heated probe and an unheated one. The larvae reacted to the touch of the heated probe with a stereotypical rolling behavior that was not exhibited when the larvae were touched by the unheated probe. Although nociception has been demonstrated in insects, there is no consensus that insects feel pain consciously

How many insects have nociceptors?

a few

Cells that detect and transmit pain are called what?

nociceptors

When were nociceptors discovered?

Nociceptors were discovered by studying the common what?

fruitfly Drosophila

Which probe did the larvae react to?

the heated probe


The salivary glands (element 30 in numbered diagram) in an insect's mouth produce saliva. The salivary ducts lead from the glands to the reservoirs and then forward through the head to an opening called the salivarium, located behind the hypopharynx. By moving its mouthparts (element 32 in numbered diagram) the insect can mix its food with saliva. The mixture of saliva and food then travels through the salivary tubes into the mouth, where it begins to break down. Some insects, like flies, have extra-oral digestion. Insects using extra-oral digestion expel digestive enzymes onto their food to break it down. This strategy allows insects to extract a significant proportion of the available nutrients from the food source.:31 The gut is where almost all of insects' digestion takes place. It can be divided into the foregut, midgut and hindgut.

What produces saliva in an insects mouth?

salivary glands

What leads from the salivary glands to the reservoirs?

salivary ducts

What is an opening through the head called?

salivarium

Where is the salivarium located?

behind the hypopharynx

Where does an insect's digestion happen?

The gut


Once food leaves the crop, it passes to the midgut (element 13 in numbered diagram), also known as the mesenteron, where the majority of digestion takes place. Microscopic projections from the midgut wall, called microvilli, increase the surface area of the wall and allow more nutrients to be absorbed; they tend to be close to the origin of the midgut. In some insects, the role of the microvilli and where they are located may vary. For example, specialized microvilli producing digestive enzymes may more likely be near the end of the midgut, and absorption near the origin or beginning of the midgut.:32

What is another name for mesenteron?

midgut

Food goes in to the midgut after leaving where?

the crop

The majority of an insects digestion happens where?

the mesenteron

What kind of projections are in the midgut wall?

Microscopic

What are microscopic projections called?

microvilli


In the hindgut (element 16 in numbered diagram), or proctodaeum, undigested food particles are joined by uric acid to form fecal pellets. The rectum absorbs 90% of the water in these fecal pellets, and the dry pellet is then eliminated through the anus (element 17), completing the process of digestion. The uric acid is formed using hemolymph waste products diffused from the Malpighian tubules (element 20). It is then emptied directly into the alimentary canal, at the junction between the midgut and hindgut. The number of Malpighian tubules possessed by a given insect varies between species, ranging from only two tubules in some insects to over 100 tubules in others.:71–72, 78–80

What is a proctodaeum?

the hindgut

What kind of food particles have uric acid?

undigested

What kind of acid forms fecal pellets?

uric acid

An insects rectum absorbs how much water?

Where is an insects dry pellet discarded through?

the anus


The reproductive system of female insects consist of a pair of ovaries, accessory glands, one or more spermathecae, and ducts connecting these parts. The ovaries are made up of a number of egg tubes, called ovarioles, which vary in size and number by species. The number of eggs that the insect is able to make vary by the number of ovarioles with the rate that eggs can be develop being also influenced by ovariole design. Female insects are able make eggs, receive and store sperm, manipulate sperm from different males, and lay eggs. Accessory glands or glandular parts of the oviducts produce a variety of substances for sperm maintenance, transport and fertilization, as well as for protection of eggs. They can produce glue and protective substances for coating eggs or tough coverings for a batch of eggs called oothecae. Spermathecae are tubes or sacs in which sperm can be stored between the time of mating and the time an egg is fertilized.:880

Female insects reproductive system contain a pair of what?

ovaries

What kind of glands are in a female insect's reproductive system?

accessory glands

What connects the parts inside a female insect's reproductive system?

ducts

Where are egg tubes are found inside of an insect?

ovaries

What are egg tubes called?

ovarioles


For males, the reproductive system is the testis, suspended in the body cavity by tracheae and the fat body. Most male insects have a pair of testes, inside of which are sperm tubes or follicles that are enclosed within a membranous sac. The follicles connect to the vas deferens by the vas efferens, and the two tubular vasa deferentia connect to a median ejaculatory duct that leads to the outside. A portion of the vas deferens is often enlarged to form the seminal vesicle, which stores the sperm before they are discharged into the female. The seminal vesicles have glandular linings that secrete nutrients for nourishment and maintenance of the sperm. The ejaculatory duct is derived from an invagination of the epidermal cells during development and, as a result, has a cuticular lining. The terminal portion of the ejaculatory duct may be sclerotized to form the intromittent organ, the aedeagus. The remainder of the male reproductive system is derived from embryonic mesoderm, except for the germ cells, or spermatogonia, which descend from the primordial pole cells very early during embryogenesis.:885

What is the male reproductive system called?

testis

Where is tracheae located?

the body cavity

Most make insects contain a pair of what?

testes

What are inside male testes?

sperm tubes

Follicles inside a male insect's reproductive system connect to what?

the vas deferens


Insect respiration is accomplished without lungs. Instead, the insect respiratory system uses a system of internal tubes and sacs through which gases either diffuse or are actively pumped, delivering oxygen directly to tissues that need it via their trachea (element 8 in numbered diagram). Since oxygen is delivered directly, the circulatory system is not used to carry oxygen, and is therefore greatly reduced. The insect circulatory system has no veins or arteries, and instead consists of little more than a single, perforated dorsal tube which pulses peristaltically. Toward the thorax, the dorsal tube (element 14) divides into chambers and acts like the insect's heart. The opposite end of the dorsal tube is like the aorta of the insect circulating the hemolymph, arthropods' fluid analog of blood, inside the body cavity.:61–65 Air is taken in through openings on the sides of the abdomen called spiracles.

Respiration for insects happens without what?

lungs

Insect's respiratory system contains sacs, and what else?

internal tubes

What gets diffused or actively pumped through an insect's respiratory system?

gases

What gets delivered to tissues in an insect's respiratory system?

oxygen

Which system inside an insect's respiratory system does not carry oxygen?

circulatory system


There are many different patterns of gas exchange demonstrated by different groups of insects. Gas exchange patterns in insects can range from continuous and diffusive ventilation, to discontinuous gas exchange.:65–68 During continuous gas exchange, oxygen is taken in and carbon dioxide is released in a continuous cycle. In discontinuous gas exchange, however, the insect takes in oxygen while it is active and small amounts of carbon dioxide are released when the insect is at rest. Diffusive ventilation is simply a form of continuous gas exchange that occurs by diffusion rather than physically taking in the oxygen. Some species of insect that are submerged also have adaptations to aid in respiration. As larvae, many insects have gills that can extract oxygen dissolved in water, while others need to rise to the water surface to replenish air supplies which may be held or trapped in special structures.

What kind of exchange is demonstrated by different insects?

gas exchange

Gas exchange patterns can contain what kind of ventilation?

diffusive ventilation

Carbon dioxide is released continuously in what kind of gas exchange?

continuous gas exchange

What gas exchanges does carbon dioxide release when the insect is resting?

discontinuous gas exchange

Diffusive ventilation occurs by what?

diffusion


The majority of insects hatch from eggs. The fertilization and development takes place inside the egg, enclosed by a shell (chorion) that consists of maternal tissue. In contrast to eggs of other arthropods, most insect eggs are drought resistant. This is because inside the chorion two additional membranes develop from embryonic tissue, the amnion and the serosa. This serosa secretes a cuticle rich in chitin that protects the embryo against desiccation. In Schizophora however the serosa does not develop, but these flies lay their eggs in damp places, such as rotting matter. Some species of insects, like the cockroach Blaptica dubia, as well as juvenile aphids and tsetse flies, are ovoviviparous. The eggs of ovoviviparous animals develop entirely inside the female, and then hatch immediately upon being laid. Some other species, such as those in the genus of cockroaches known as Diploptera, are viviparous, and thus gestate inside the mother and are born alive.:129, 131, 134–135 Some insects, like parasitic wasps, show polyembryony, where a single fertilized egg divides into many and in some cases thousands of separate embryos.:136–137 Insects may be univoltine, bivoltine or multivoltine, i.e. they may have one, two or many broods (generations) in a year.

Where are insects hatched from?

eggs.

Fertilization happens where?

inside the egg

Fertilization and what else happens inside the egg?

development

Chorion is another word for what?

shell

Broods is another term for what word?

generations


Other developmental and reproductive variations include haplodiploidy, polymorphism, paedomorphosis or peramorphosis, sexual dimorphism, parthenogenesis and more rarely hermaphroditism.:143 In haplodiploidy, which is a type of sex-determination system, the offspring's sex is determined by the number of sets of chromosomes an individual receives. This system is typical in bees and wasps. Polymorphism is where a species may have different morphs or forms, as in the oblong winged katydid, which has four different varieties: green, pink and yellow or tan. Some insects may retain phenotypes that are normally only seen in juveniles; this is called paedomorphosis. In peramorphosis, an opposite sort of phenomenon, insects take on previously unseen traits after they have matured into adults. Many insects display sexual dimorphism, in which males and females have notably different appearances, such as the moth Orgyia recens as an exemplar of sexual dimorphism in insects.

Polymophism is a developmental and reproductive what?

variations

Haplodiploidy is what type of system?

sex-determination system

The number of chromosome sets determines the offspring's what?

sex

The sex-determination system is found in which insects?

bees and wasps

Polymophism species have different forms or what else?

morphs


Some insects use parthenogenesis, a process in which the female can reproduce and give birth without having the eggs fertilized by a male. Many aphids undergo a form of parthenogenesis, called cyclical parthenogenesis, in which they alternate between one or many generations of asexual and sexual reproduction. In summer, aphids are generally female and parthenogenetic; in the autumn, males may be produced for sexual reproduction. Other insects produced by parthenogenesis are bees, wasps and ants, in which they spawn males. However, overall, most individuals are female, which are produced by fertilization. The males are haploid and the females are diploid. More rarely, some insects display hermaphroditism, in which a given individual has both male and female reproductive organs.

How many insects use parthenogenesis?

Some

GIving birth without fertilized eggs is called what?

parthenogenesis

What usually partakes in a form of parthenogenesis?

aphids

Aphis have asexual and sexual what?

reproduction

Aphis are usually female and what else during the summer?

parthenogenetic


Hemimetabolous insects, those with incomplete metamorphosis, change gradually by undergoing a series of molts. An insect molts when it outgrows its exoskeleton, which does not stretch and would otherwise restrict the insect's growth. The molting process begins as the insect's epidermis secretes a new epicuticle inside the old one. After this new epicuticle is secreted, the epidermis releases a mixture of enzymes that digests the endocuticle and thus detaches the old cuticle. When this stage is complete, the insect makes its body swell by taking in a large quantity of water or air, which makes the old cuticle split along predefined weaknesses where the old exocuticle was thinnest.:142

Incomplete metamorphosis insects are called?

Hemimetabolous

What kind of metamorphosis do hemimetabolous insects undergo?

incomplete

Do hemimetabolous insects change quickly or gradually?

gradually

Hemimetabolous insects gradually change by a series of what?

molts

Insect's molt when they outgrow what?

exoskeleton


Holometabolism, or complete metamorphosis, is where the insect changes in four stages, an egg or embryo, a larva, a pupa and the adult or imago. In these species, an egg hatches to produce a larva, which is generally worm-like in form. This worm-like form can be one of several varieties: eruciform (caterpillar-like), scarabaeiform (grub-like), campodeiform (elongated, flattened and active), elateriform (wireworm-like) or vermiform (maggot-like). The larva grows and eventually becomes a pupa, a stage marked by reduced movement and often sealed within a cocoon. There are three types of pupae: obtect, exarate or coarctate. Obtect pupae are compact, with the legs and other appendages enclosed. Exarate pupae have their legs and other appendages free and extended. Coarctate pupae develop inside the larval skin.:151 Insects undergo considerable change in form during the pupal stage, and emerge as adults. Butterflies are a well-known example of insects that undergo complete metamorphosis, although most insects use this life cycle. Some insects have evolved this system to hypermetamorphosis.

What is a complete metamorphosis called?

Holometabolism

How many stages happen in complete metamorphosis?

four stages

What is another word for egg?

embryo

What is an imago?

the adult

Name an example of an insect that undergoes complete metamorphosis?

Butterflies


Many insects possess very sensitive and, or specialized organs of perception. Some insects such as bees can perceive ultraviolet wavelengths, or detect polarized light, while the antennae of male moths can detect the pheromones of female moths over distances of many kilometers. The yellow paper wasp (Polistes versicolor) is known for its wagging movements as a form of communication within the colony; it can waggle with a frequency of 10.6±2.1 Hz (n=190). These wagging movements can signal the arrival of new material into the nest and aggression between workers can be used to stimulate others to increase foraging expeditions. There is a pronounced tendency for there to be a trade-off between visual acuity and chemical or tactile acuity, such that most insects with well-developed eyes have reduced or simple antennae, and vice versa. There are a variety of different mechanisms by which insects perceive sound, while the patterns are not universal, insects can generally hear sound if they can produce it. Different insect species can have varying hearing, though most insects can hear only a narrow range of frequencies related to the frequency of the sounds they can produce. Mosquitoes have been found to hear up to 2 kHz., and some grasshoppers can hear up to 50 kHz. Certain predatory and parasitic insects can detect the characteristic sounds made by their prey or hosts, respectively. For instance, some nocturnal moths can perceive the ultrasonic emissions of bats, which helps them avoid predation.:87–94 Insects that feed on blood have special sensory structures that can detect infrared emissions, and use them to home in on their hosts.

Insects have specialized organs of what kind?

perception

Insect organs are described as sensitive and what?

specialized

What kind of insect can detect ultraviolet wavelengths?

bees

Bees can detect what kind of light?

polarized light

What is a Polistes versicolor?

yellow paper wasp


Some insects display a rudimentary sense of numbers, such as the solitary wasps that prey upon a single species. The mother wasp lays her eggs in individual cells and provides each egg with a number of live caterpillars on which the young feed when hatched. Some species of wasp always provide five, others twelve, and others as high as twenty-four caterpillars per cell. The number of caterpillars is different among species, but always the same for each sex of larva. The male solitary wasp in the genus Eumenes is smaller than the female, so the mother of one species supplies him with only five caterpillars; the larger female receives ten caterpillars in her cell.

Insects have what kind of sense of numbers?

rudimentary

Which insect displays a rudimentary sense of numbers?

solitary wasps

What kind of species does a solitary wasp prey upon?

single

What does the mother wasp provide for her eggs when they hatch?

caterpillars

Is the male solitary wasp bigger or smaller than the female solitary wasp?

smaller


A few insects, such as members of the families Poduridae and Onychiuridae (Collembola), Mycetophilidae (Diptera) and the beetle families Lampyridae, Phengodidae, Elateridae and Staphylinidae are bioluminescent. The most familiar group are the fireflies, beetles of the family Lampyridae. Some species are able to control this light generation to produce flashes. The function varies with some species using them to attract mates, while others use them to lure prey. Cave dwelling larvae of Arachnocampa (Mycetophilidae, Fungus gnats) glow to lure small flying insects into sticky strands of silk. Some fireflies of the genus Photuris mimic the flashing of female Photinus species to attract males of that species, which are then captured and devoured. The colors of emitted light vary from dull blue (Orfelia fultoni, Mycetophilidae) to the familiar greens and the rare reds (Phrixothrix tiemanni, Phengodidae).

What is another name for Colleobola?

Onychiuridae

Mycetophilldae is another name for what?

Diptera

Phengodidae is party of what insect family?

beetle

Elateridae and Staphylinidae are what kind of luminescent?

bioluminescent

What kind of fly mimics the flashing of female Photinus to attract males?

fireflies


Most insects, except some species of cave crickets, are able to perceive light and dark. Many species have acute vision capable of detecting minute movements. The eyes may include simple eyes or ocelli as well as compound eyes of varying sizes. Many species are able to detect light in the infrared, ultraviolet and the visible light wavelengths. Color vision has been demonstrated in many species and phylogenetic analysis suggests that UV-green-blue trichromacy existed from at least the Devonian period between 416 and 359 million years ago.

Most insects are able to perceive darkness and what else?

light

What insect is not abel to perceive light and dark?

cave crickets

Most insects have what kind of vision?

acute

Insects notice what type of movement?

minute

Many insects are able to see visible light, ultraviolet, and what other kind of light?

infrared


Insects were the earliest organisms to produce and sense sounds. Insects make sounds mostly by mechanical action of appendages. In grasshoppers and crickets, this is achieved by stridulation. Cicadas make the loudest sounds among the insects by producing and amplifying sounds with special modifications to their body and musculature. The African cicada Brevisana brevis has been measured at 106.7 decibels at a distance of 50 cm (20 in). Some insects, such as the Helicoverpa zeamoths, hawk moths and Hedylid butterflies, can hear ultrasound and take evasive action when they sense that they have been detected by bats. Some moths produce ultrasonic clicks that were once thought to have a role in jamming bat echolocation. The ultrasonic clicks were subsequently found to be produced mostly by unpalatable moths to warn bats, just as warning colorations are used against predators that hunt by sight. Some otherwise palatable moths have evolved to mimic these calls. More recently, the claim that some moths can jam bat sonar has been revisited. Ultrasonic recording and high-speed infrared videography of bat-moth interactions suggest the palatable tiger moth really does defend against attacking big brown bats using ultrasonic clicks that jam bat sonar.

What were the earliest organisms to produce sound?

Insects

Insects can sense what?

sounds

Insect sounds come from what kind of action?

mechanical

The mechanical action of what allows insects t make sound?

appendages

Moths create what kind of click sounds?

ultrasonic


Very low sounds are also produced in various species of Coleoptera, Hymenoptera, Lepidoptera, Mantodea and Neuroptera. These low sounds are simply the sounds made by the insect's movement. Through microscopic stridulatory structures located on the insect's muscles and joints, the normal sounds of the insect moving are amplified and can be used to warn or communicate with other insects. Most sound-making insects also have tympanal organs that can perceive airborne sounds. Some species in Hemiptera, such as the corixids (water boatmen), are known to communicate via underwater sounds. Most insects are also able to sense vibrations transmitted through surfaces.

What sound volume is produced by Coleoptera?

low

Low insect sounds are made by the insect's what?

movement

Low insect sounds can be heard through what?

microscopic stridulatory structures

Insect moving sounds are used to warn and do what with other insects?

communicate

Corixids are able to communicate with what type of sounds?

underwater


Some species use vibrations for communicating within members of the same species, such as to attract mates as in the songs of the shield bug Nezara viridula. Vibrations can also be used to communicate between entirely different species; lycaenid (gossamer-winged butterfly) caterpillars which are myrmecophilous (living in a mutualistic association with ants) communicate with ants in this way. The Madagascar hissing cockroach has the ability to press air through its spiracles to make a hissing noise as a sign of aggression; the Death's-head Hawkmoth makes a squeaking noise by forcing air out of their pharynx when agitated, which may also reduce aggressive worker honey bee behavior when the two are in close proximity.

What are used by insects to communicate with members of the same species?

vibrations

Vibrations are used to communicate with members of the same species, and what other species?

different species

Which insects has a song to attract males from the same species?

Nezara viridula

What is a lycaenid caterpillar?

gossamer-winged butterfly

Living in association with ants is called what?

myrmecophilous


Chemical communications in animals rely on a variety of aspects including taste and smell. Chemoreception is the physiological response of a sense organ (i.e. taste or smell) to a chemical stimulus where the chemicals act as signals to regulate the state or activity of a cell. A semiochemical is a message-carrying chemical that is meant to attract, repel, and convey information. Types of semiochemicals include pheromones and kairomones. One example is the butterfly Phengaris arion which uses chemical signals as a form of mimicry to aid in predation.

Animal taste and smell rely on what kind of communication?

Chemical

What is the physiological response of a sense organ called?

Chemoreception

Chemical stimuli are signals that regulate the activity of what?

a cell

What is a message-carrying chemical called?

semiochemical

Kairomones are a type of what?

semiochemicals


In addition to the use of sound for communication, a wide range of insects have evolved chemical means for communication. These chemicals, termed semiochemicals, are often derived from plant metabolites include those meant to attract, repel and provide other kinds of information. Pheromones, a type of semiochemical, are used for attracting mates of the opposite sex, for aggregating conspecific individuals of both sexes, for deterring other individuals from approaching, to mark a trail, and to trigger aggression in nearby individuals. Allomonea benefit their producer by the effect they have upon the receiver. Kairomones benefit their receiver instead of their producer. Synomones benefit the producer and the receiver. While some chemicals are targeted at individuals of the same species, others are used for communication across species. The use of scents is especially well known to have developed in social insects.:96–105

Insects use sound and what other means for communication?

chemical means

The chemicals used by insects to communicate are called what?

semiochemicals

Semiochemicals come from where?

plant metabolites

Insect chemicals are used to attract and what else?

repel

What insect chemical benefits both the receiver and the producer?

Synomones


Social insects, such as termites, ants and many bees and wasps, are the most familiar species of eusocial animal. They live together in large well-organized colonies that may be so tightly integrated and genetically similar that the colonies of some species are sometimes considered superorganisms. It is sometimes argued that the various species of honey bee are the only invertebrates (and indeed one of the few non-human groups) to have evolved a system of abstract symbolic communication where a behavior is used to represent and convey specific information about something in the environment. In this communication system, called dance language, the angle at which a bee dances represents a direction relative to the sun, and the length of the dance represents the distance to be flown.:309–311 Though perhaps not as advanced as honey bees, bumblebees also potentially have some social communication behaviors. Bombus terrestris, for example, exhibit a faster learning curve for visiting unfamiliar, yet rewarding flowers, when they can see a conspecific foraging on the same species.

Termites are considered what type of insect?

Social

Termites, bees, wasps, and what other insect are social insects?

ants

What is another term for social insect?

eusocial animal

Social insects live in well organized what?

colonies

The method that a bee dances is called what?

dance language


Only insects which live in nests or colonies demonstrate any true capacity for fine-scale spatial orientation or homing. This can allow an insect to return unerringly to a single hole a few millimeters in diameter among thousands of apparently identical holes clustered together, after a trip of up to several kilometers' distance. In a phenomenon known as philopatry, insects that hibernate have shown the ability to recall a specific location up to a year after last viewing the area of interest. A few insects seasonally migrate large distances between different geographic regions (e.g., the overwintering areas of the Monarch butterfly).:14

Insects with fine scale spatial orientation live in colonies and where else?

nests

Some insects have a fine scale spatial orientation and/or what else?

homing

Spacial orientation/homing allows an insect to return to one specific hole among how many?

thousands

An insect recalling a specific location for up to a year is called what?

philopatry

An insect that can recall a specific location for up to a year does what?

hibernate


The eusocial insects build nest, guard eggs, and provide food for offspring full-time (see Eusociality). Most insects, however, lead short lives as adults, and rarely interact with one another except to mate or compete for mates. A small number exhibit some form of parental care, where they will at least guard their eggs, and sometimes continue guarding their offspring until adulthood, and possibly even feeding them. Another simple form of parental care is to construct a nest (a burrow or an actual construction, either of which may be simple or complex), store provisions in it, and lay an egg upon those provisions. The adult does not contact the growing offspring, but it nonetheless does provide food. This sort of care is typical for most species of bees and various types of wasps.

Eusocial insects provide food for their offspring full-time or part-time?

full-time

What do eusocial insects guard?

eggs

What do eusocial insects build?

nest

Most eusocial insects lead what kind of life once becoming an adult?

short

An adult eusocial insect does not contact it's what?

growing offspring


Insects are the only group of invertebrates to have developed flight. The evolution of insect wings has been a subject of debate. Some entomologists suggest that the wings are from paranotal lobes, or extensions from the insect's exoskeleton called the nota, called the paranotal theory. Other theories are based on a pleural origin. These theories include suggestions that wings originated from modified gills, spiracular flaps or as from an appendage of the epicoxa. The epicoxal theory suggests the insect wings are modified epicoxal exites, a modified appendage at the base of the legs or coxa. In the Carboniferous age, some of the Meganeura dragonflies had as much as a 50 cm (20 in) wide wingspan. The appearance of gigantic insects has been found to be consistent with high atmospheric oxygen. The respiratory system of insects constrains their size, however the high oxygen in the atmosphere allowed larger sizes. The largest flying insects today are much smaller and include several moth species such as the Atlas moth and the White Witch (Thysania agrippina).

Insects are the only invertebrates that have evolved into what?

flight

What part of the insect has been up for debate?

wings

Wings from the paranotal lobes are based on what theory?

paranotal theory

Wings from modified gills is from what origin?

pleural origin

The epicoxal theory suggests insect wings are modified what?

epicoxal exites


Many adult insects use six legs for walking and have adopted a tripedal gait. The tripedal gait allows for rapid walking while always having a stable stance and has been studied extensively in cockroaches. The legs are used in alternate triangles touching the ground. For the first step, the middle right leg and the front and rear left legs are in contact with the ground and move the insect forward, while the front and rear right leg and the middle left leg are lifted and moved forward to a new position. When they touch the ground to form a new stable triangle the other legs can be lifted and brought forward in turn and so on. The purest form of the tripedal gait is seen in insects moving at high speeds. However, this type of locomotion is not rigid and insects can adapt a variety of gaits. For example, when moving slowly, turning, or avoiding obstacles, four or more feet may be touching the ground. Insects can also adapt their gait to cope with the loss of one or more limbs.

How many legs do adult insects contain?

six

Most adult insects have adopted what kind of gait?

tripedal

The tripedal gait allows what kind of walking?

rapid

Insects can adopt how many gaits?

a variety

Insects can change their gait to deal with the loss of what?

limbs


Cockroaches are among the fastest insect runners and, at full speed, adopt a bipedal run to reach a high velocity in proportion to their body size. As cockroaches move very quickly, they need to be video recorded at several hundred frames per second to reveal their gait. More sedate locomotion is seen in the stick insects or walking sticks (Phasmatodea). A few insects have evolved to walk on the surface of the water, especially members of the Gerridae family, commonly known as water striders. A few species of ocean-skaters in the genus Halobates even live on the surface of open oceans, a habitat that has few insect species.

What kind of locomotion is seen in stick insects?

sedate

What is another name for walking stick insects?

Phasmatodea

Some insects can walk on top of what?

water

What insect can walk on the surface of water?

water striders

Water striders are part of what insect family?

Gerridae


Many of these species have adaptations to help in under-water locomotion. Water beetles and water bugs have legs adapted into paddle-like structures. Dragonfly naiads use jet propulsion, forcibly expelling water out of their rectal chamber. Some species like the water striders are capable of walking on the surface of water. They can do this because their claws are not at the tips of the legs as in most insects, but recessed in a special groove further up the leg; this prevents the claws from piercing the water's surface film. Other insects such as the Rove beetle Stenus are known to emit pygidial gland secretions that reduce surface tension making it possible for them to move on the surface of water by Marangoni propulsion (also known by the German term Entspannungsschwimmen).

Water beetles have legs of what type of structure?

paddle-like

Dragonflys use what kind of propulsion?

jet

Dragonflys shoot water from where?

rectal chamber

Water striders have what kind of special groove up their leg?

recessed

Rove beetle Stenus emit what type of gland secretions?

pygidial


Insect ecology is the scientific study of how insects, individually or as a community, interact with the surrounding environment or ecosystem.:3 Insects play one of the most important roles in their ecosystems, which includes many roles, such as soil turning and aeration, dung burial, pest control, pollination and wildlife nutrition. An example is the beetles, which are scavengers that feed on dead animals and fallen trees and thereby recycle biological materials into forms found useful by other organisms. These insects, and others, are responsible for much of the process by which topsoil is created.:3, 218–228

Learning how insects interact with the surrounding environment is called what?

Insect ecology

Another term for surrounding environment is what?

ecosystem

What kind of role do insects play in their ecosystem?

important

What type of burial do insects engage in?

dung

Beetles are also known as what?

scavengers


Camouflage is an important defense strategy, which involves the use of coloration or shape to blend into the surrounding environment. This sort of protective coloration is common and widespread among beetle families, especially those that feed on wood or vegetation, such as many of the leaf beetles (family Chrysomelidae) or weevils. In some of these species, sculpturing or various colored scales or hairs cause the beetle to resemble bird dung or other inedible objects. Many of those that live in sandy environments blend in with the coloration of the substrate. Most phasmids are known for effectively replicating the forms of sticks and leaves, and the bodies of some species (such as O. macklotti and Palophus centaurus) are covered in mossy or lichenous outgrowths that supplement their disguise. Some species have the ability to change color as their surroundings shift (B. scabrinota, T. californica). In a further behavioral adaptation to supplement crypsis, a number of species have been noted to perform a rocking motion where the body is swayed from side to side that is thought to reflect the movement of leaves or twigs swaying in the breeze. Another method by which stick insects avoid predation and resemble twigs is by feigning death (catalepsy), where the insect enters a motionless state that can be maintained for a long period. The nocturnal feeding habits of adults also aids Phasmatodea in remaining concealed from predators.

What is an important defense strategy for insects to survive?

Camouflage

What does coloration and shape help an insect do in the surrounding environment?

blend

Protective coloring is common in what insect family?

beetle

What is Chrysomelidae?

leaf beetles

A beetle can resemble what kind of dung?

bird dung


Another defense that often uses color or shape to deceive potential enemies is mimicry. A number of longhorn beetles (family Cerambycidae) bear a striking resemblance to wasps, which helps them avoid predation even though the beetles are in fact harmless. Batesian and Müllerian mimicry complexes are commonly found in Lepidoptera. Genetic polymorphism and natural selection give rise to otherwise edible species (the mimic) gaining a survival advantage by resembling inedible species (the model). Such a mimicry complex is referred to as Batesian and is most commonly known by the mimicry by the limenitidine Viceroy butterfly of the inedible danaine Monarch. Later research has discovered that the Viceroy is, in fact more toxic than the Monarch and this resemblance should be considered as a case of Müllerian mimicry. In Müllerian mimicry, inedible species, usually within a taxonomic order, find it advantageous to resemble each other so as to reduce the sampling rate by predators who need to learn about the insects' inedibility. Taxa from the toxic genus Heliconius form one of the most well known Müllerian complexes.

Mimicry is another type of what kid of strategy?

defense

Mimicry is used to do what to potential enemies?

deceive

Longhorn beetles look similar to what other insect?

wasps

Mimicry complexes are usually found where?

in Lepidoptera

What is a well known Mullerian complex?

Taxa


Chemical defense is another important defense found amongst species of Coleoptera and Lepidoptera, usually being advertised by bright colors, such as the Monarch butterfly. They obtain their toxicity by sequestering the chemicals from the plants they eat into their own tissues. Some Lepidoptera manufacture their own toxins. Predators that eat poisonous butterflies and moths may become sick and vomit violently, learning not to eat those types of species; this is actually the basis of Müllerian mimicry. A predator who has previously eaten a poisonous lepidopteran may avoid other species with similar markings in the future, thus saving many other species as well. Some ground beetles of the Carabidae family can spray chemicals from their abdomen with great accuracy, to repel predators.

What kind of defense is found in the Coleoptera species?

Chemical

What chemical defense is used by the Monarch butterfly?

bright colors

Insects become toxic by doing what with the chemicals from plants?

sequestering

Which insect manufactures it's own toxins?

Lepidoptera

Some beetles can spray what from their abdomen?

chemicals


Pollination is the process by which pollen is transferred in the reproduction of plants, thereby enabling fertilisation and sexual reproduction. Most flowering plants require an animal to do the transportation. While other animals are included as pollinators, the majority of pollination is done by insects. Because insects usually receive benefit for the pollination in the form of energy rich nectar it is a grand example of mutualism. The various flower traits (and combinations thereof) that differentially attract one type of pollinator or another are known as pollination syndromes. These arose through complex plant-animal adaptations. Pollinators find flowers through bright colorations, including ultraviolet, and attractant pheromones. The study of pollination by insects is known as anthecology.

Pollen transferred in the reproduction of plants is called?

Pollination

What is required to transport pollen?

an animal

Most pollination is completed by what?

insects

What do insects receive in return for pollination?

energy rich nectar

Flowers that allow only one type of pollinator is called what?

pollination syndromes


Many insects are considered pests by humans. Insects commonly regarded as pests include those that are parasitic (e.g. lice, bed bugs), transmit diseases (mosquitoes, flies), damage structures (termites), or destroy agricultural goods (locusts, weevils). Many entomologists are involved in various forms of pest control, as in research for companies to produce insecticides, but increasingly rely on methods of biological pest control, or biocontrol. Biocontrol uses one organism to reduce the population density of another organism — the pest — and is considered a key element of integrated pest management.

Humans consider insects as what?

pests

Lice and bed bugs are considered what kind of insect?

parasitic

Flies and what other kind of insect transmit diseases?

mosquitoes

What kind of insect can damage architectural structures?

termites

Locusts destroy what?

agricultural goods


Although pest insects attract the most attention, many insects are beneficial to the environment and to humans. Some insects, like wasps, bees, butterflies and ants, pollinate flowering plants. Pollination is a mutualistic relationship between plants and insects. As insects gather nectar from different plants of the same species, they also spread pollen from plants on which they have previously fed. This greatly increases plants' ability to cross-pollinate, which maintains and possibly even improves their evolutionary fitness. This ultimately affects humans since ensuring healthy crops is critical to agriculture. As well as pollination ants help with seed distribution of plants. This helps to spread the plants which increases plant diversity. This leads to an overall better environment. A serious environmental problem is the decline of populations of pollinator insects, and a number of species of insects are now cultured primarily for pollination management in order to have sufficient pollinators in the field, orchard or greenhouse at bloom time.:240–243 Another solution, as shown in Delaware, has been to raise native plants to help support native pollinators like L. vierecki. Insects also produce useful substances such as honey, wax, lacquer and silk. Honey bees have been cultured by humans for thousands of years for honey, although contracting for crop pollination is becoming more significant for beekeepers. The silkworm has greatly affected human history, as silk-driven trade established relationships between China and the rest of the world.

What kind of insects attract the most attention from humans?

pest insects

Many insects are what to the environment?

beneficial

What do bees, wasps, butterflies, and ants do to flowers?

pollinate

What do insects gather from plants?

nectar

What kind of environmental problem would occur without pollination?

serious


Insectivorous insects, or insects which feed on other insects, are beneficial to humans because they eat insects that could cause damage to agriculture and human structures. For example, aphids feed on crops and cause problems for farmers, but ladybugs feed on aphids, and can be used as a means to get significantly reduce pest aphid populations. While birds are perhaps more visible predators of insects, insects themselves account for the vast majority of insect consumption. Ants also help control animal populations by consuming small vertebrates. Without predators to keep them in check, insects can undergo almost unstoppable population explosions.:328–348:400

What insects feed on other insects?

Insectivorous

Insectivorous insects are beneficial or harmful to humans?

beneficial

What insect feeds on aphids?

ladybugs

What are the most visible predators of insects?

birds

What is the largest consumer of insects?

insects themselves


Insects play important roles in biological research. For example, because of its small size, short generation time and high fecundity, the common fruit fly Drosophila melanogaster is a model organism for studies in the genetics of higher eukaryotes. D. melanogaster has been an essential part of studies into principles like genetic linkage, interactions between genes, chromosomal genetics, development, behavior and evolution. Because genetic systems are well conserved among eukaryotes, understanding basic cellular processes like DNA replication or transcription in fruit flies can help to understand those processes in other eukaryotes, including humans. The genome of D. melanogaster was sequenced in 2000, reflecting the organism's important role in biological research. It was found that 70% of the fly genome is similar to the human genome, supporting the evolution theory.

Insects play prominent roles in what?

biological research

What is a common insect used for research purposes?

fruit fly Drosophila melanogaster

Drosophila has helped develop principles in what kind of linkage?

genetic

Genetic systems are conserved among what?

eukaryotes

What percent of the fly genome is similar to the human genome


In some cultures, insects, especially deep-fried cicadas, are considered to be delicacies, while in other places they form part of the normal diet. Insects have a high protein content for their mass, and some authors suggest their potential as a major source of protein in human nutrition.:10–13 In most first-world countries, however, entomophagy (the eating of insects), is taboo. Since it is impossible to entirely eliminate pest insects from the human food chain, insects are inadvertently present in many foods, especially grains. Food safety laws in many countries do not prohibit insect parts in food, but rather limit their quantity. According to cultural materialist anthropologist Marvin Harris, the eating of insects is taboo in cultures that have other protein sources such as fish or livestock.

Insects are considered as what in some cultures?

delicacies

What deep-fried insect is part of the normal diet in some cultures?

cicadas

Insects have what kind of protein content?

high

What is the term for eating insects?

entomophagy

Where is eating insects considered taboo?

first-world countries


Scarab beetles held religious and cultural symbolism in Old Egypt, Greece and some shamanistic Old World cultures. The ancient Chinese regarded cicadas as symbols of rebirth or immortality. In Mesopotamian literature, the epic poem of Gilgamesh has allusions to Odonata which signify the impossibility of immortality. Amongst the Aborigines of Australia of the Arrernte language groups, honey ants and witchety grubs served as personal clan totems. In the case of the 'San' bush-men of the Kalahari, it is the praying mantis which holds much cultural significance including creation and zen-like patience in waiting.:9

What ancient world insect is considered symbolic?

Scarab beetles

Cicadas symbolize immortality in what culture?

Chinese

What kind of ants are symbolic among the Australian Aborigines?

honey ants

The praying mantis symbolizes patience and what else?

creation

Witchety grubs serve as personal clan totems in what country?

Australia


Even though there is a broad scientific agreement that essentialist and typological conceptualizations of race are untenable, scientists around the world continue to conceptualize race in widely differing ways, some of which have essentialist implications. While some researchers sometimes use the concept of race to make distinctions among fuzzy sets of traits, others in the scientific community suggest that the idea of race often is used in a naive or simplistic way,[page needed] and argue that, among humans, race has no taxonomic significance by pointing out that all living humans belong to the same species, Homo sapiens, and subspecies, Homo sapiens sapiens.

What do all living humans belong to?

the same species

What species are all humans?

Homo sapiens

Race has no taxonomic significance among whom?

humans

What set of traits do some scientists use race to make distinctions among?

fuzzy

How do scientists around the world continue to conceptualize race?

in widely differing ways


There is a wide consensus that the racial categories that are common in everyday usage are socially constructed, and that racial groups cannot be biologically defined. Nonetheless, some scholars argue that racial categories obviously correlate with biological traits (e.g. phenotype) to some degree, and that certain genetic markers have varying frequencies among human populations, some of which correspond more or less to traditional racial groupings. For this reason, there is no current consensus about whether racial categories can be considered to have significance for understanding human genetic variation.

What type of group can't be biologically defined?

racial

What type of categorization in every day usage is there wide agreement it is only a social construct?

racial

What do some people contend racial categories are obviously correlated with?

biological traits

Some genetic markers have varying frequencies among what populations?

human

What is the majority opinion on whether racial categories can be considered to have impact on human genetic variation?

no current consensus


When people define and talk about a particular conception of race, they create a social reality through which social categorization is achieved. In this sense, races are said to be social constructs. These constructs develop within various legal, economic, and sociopolitical contexts, and may be the effect, rather than the cause, of major social situations. While race is understood to be a social construct by many, most scholars agree that race has real material effects in the lives of people through institutionalized practices of preference and discrimination.

How do people create a social reality in which social categorization is achieved?

define and talk about a particular conception of race

What can be said to be a social construct?

races

What contexts do racial social constructs develop within?

legal, economic, and sociopolitical

Constructs may be the result rather than the inciter of what?

major social situations

What effect does race have in the lives of people?

real material


Socioeconomic factors, in combination with early but enduring views of race, have led to considerable suffering within disadvantaged racial groups. Racial discrimination often coincides with racist mindsets, whereby the individuals and ideologies of one group come to perceive the members of an outgroup as both racially defined and morally inferior. As a result, racial groups possessing relatively little power often find themselves excluded or oppressed, while hegemonic individuals and institutions are charged with holding racist attitudes. Racism has led to many instances of tragedy, including slavery and genocide.

Socioeconomic factors and enduring views on race has led to what for certain racial groups?

considerable suffering

What is discrimination often paired with?

racist mindsets

What do members of one group typically perceive the moral standing of outgroups as?

inferior

What do groups with less power often find themselves?

excluded or oppressed

What has led to many tragic instances of events like slavery and genocide?

Racism


In some countries, law enforcement uses race to profile suspects. This use of racial categories is frequently criticized for perpetuating an outmoded understanding of human biological variation, and promoting stereotypes. Because in some societies racial groupings correspond closely with patterns of social stratification, for social scientists studying social inequality, race can be a significant variable. As sociological factors, racial categories may in part reflect subjective attributions, self-identities, and social institutions.

What does law enforcement in some countries use to profile suspects?

race

Why is using racial categorization for profiling often criticized?

perpetuating an outmoded understanding of human biological variation

What promotes stereotypes?

use of racial categories

Who can race serve as a significant factor when studying social inequality?

social scientists

What may in part reflect subjective attributes, self-identities and social institutions?

sociological factors


Groups of humans have always identified themselves as distinct from neighboring groups, but such differences have not always been understood to be natural, immutable and global. These features are the distinguishing features of how the concept of race is used today. In this way the idea of race as we understand it today came about during the historical process of exploration and conquest which brought Europeans into contact with groups from different continents, and of the ideology of classification and typology found in the natural sciences.

What have human groups always considered themselves as compared to other nearby groups?

distinct

What have differences among groups not typically been perceived as being?

natural, immutable and global

During which process did our current idea of race come about?

exploration and conquest

Where did Europeans come into contact with other groups?

different continents

What ideaology is found in the natural sciences?

classification and typology


The European concept of "race", along with many of the ideas now associated with the term, arose at the time of the scientific revolution, which introduced and privileged the study of natural kinds, and the age of European imperialism and colonization which established political relations between Europeans and peoples with distinct cultural and political traditions. As Europeans encountered people from different parts of the world, they speculated about the physical, social, and cultural differences among various human groups. The rise of the Atlantic slave trade, which gradually displaced an earlier trade in slaves from throughout the world, created a further incentive to categorize human groups in order to justify the subordination of African slaves. Drawing on Classical sources and upon their own internal interactions — for example, the hostility between the English and Irish powerfully influenced early European thinking about the differences between people — Europeans began to sort themselves and others into groups based on physical appearance, and to attribute to individuals belonging to these groups behaviors and capacities which were claimed to be deeply ingrained. A set of folk beliefs took hold that linked inherited physical differences between groups to inherited intellectual, behavioral, and moral qualities. Similar ideas can be found in other cultures, for example in China, where a concept often translated as "race" was associated with supposed common descent from the Yellow Emperor, and used to stress the unity of ethnic groups in China. Brutal conflicts between ethnic groups have existed throughout history and across the world.

When did many of the ideas associated with the term "race" arise?

time of the scientific revolution

What created relations between Europeans and people with different cultures?

colonization

Who speculated about the observable difference among different groups of humans?

Europeans

Justifying the subordination of what group was one of the incentives to categorize human groups?

African slaves

What groups has there always been brutal conflict between?

ethnic


The first post-Classical published classification of humans into distinct races seems to be François Bernier's Nouvelle division de la terre par les différents espèces ou races qui l'habitent ("New division of Earth by the different species or races which inhabit it"), published in 1684. In the 18th century the differences among human groups became a focus of scientific investigation. But the scientific classification of phenotypic variation was frequently coupled with racist ideas about innate predispositions of different groups, always attributing the most desirable features to the White, European race and arranging the other races along a continuum of progressively undesirable attributes. The 1735 classification of Carl Linnaeus, inventor of zoological taxonomy, divided the human race Homo sapiens into continental varieties of europaeus, asiaticus, americanus, and afer, each associated with a different humour: sanguine, melancholic, choleric, and phlegmatic, respectively. Homo sapiens europaeus was described as active, acute, and adventurous, whereas Homo sapiens afer was said to be crafty, lazy, and careless.

Who was the author of the first published book classifying humans into distinct races?

François Bernier

In what century did differences among human groups become a focus of science?

18th century

What race was typically ascribed the most desirable features?

White

How was Homo sapiens europaeus described as?

active, acute, and adventurous

What attributes were bestowed on homo spaiens afer?

crafty, lazy, and careless


The 1775 treatise "The Natural Varieties of Mankind", by Johann Friedrich Blumenbach proposed five major divisions: the Caucasoid race, Mongoloid race, Ethiopian race (later termed Negroid, and not to be confused with the narrower Ethiopid race), American Indian race, and Malayan race, but he did not propose any hierarchy among the races. Blumenbach also noted the graded transition in appearances from one group to adjacent groups and suggested that "one variety of mankind does so sensibly pass into the other, that you cannot mark out the limits between them".

What year was Blumenbach's treatise published?

How many divisions did Blumenbach's treatise specify?

five

What race was later renamed to Negroid?

Ethiopian

What type of transition was noted from one group to the next?

graded

What can one not mark between the variety of mankind?

limits


From the 17th through 19th centuries, the merging of folk beliefs about group differences with scientific explanations of those differences produced what one scholar has called an "ideology of race". According to this ideology, races are primordial, natural, enduring and distinct. It was further argued that some groups may be the result of mixture between formerly distinct populations, but that careful study could distinguish the ancestral races that had combined to produce admixed groups. Subsequent influential classifications by Georges Buffon, Petrus Camper and Christoph Meiners all classified "Negros" as inferior to Europeans. In the United States the racial theories of Thomas Jefferson were influential. He saw Africans as inferior to Whites especially in regards to their intellect, and imbued with unnatural sexual appetites, but described Native Americans as equals to whites.

What did the merging of superstitious beliefs and scientific ones regarding group differences produce?

an "ideology of race"

What were races considered to be, according to the ideology of race?

primordial, natural, enduring and distinct

How might some groups have resulted, according to the ideology?

mixture between formerly distinct populations

What group was identified as being inferior to Europeans?

Negros

Who particularly noted the unnatural sexual appetites of Africans?

Thomas Jefferson


In the last two decades of the 18th century, the theory of polygenism, the belief that different races had evolved separately in each continent and shared no common ancestor, was advocated in England by historian Edward Long and anatomist Charles White, in Germany by ethnographers Christoph Meiners and Georg Forster, and in France by Julien-Joseph Virey. In the US, Samuel George Morton, Josiah Nott and Louis Agassiz promoted this theory in the mid-nineteenth century. Polygenism was popular and most widespread in the 19th century, culminating in the founding of the Anthropological Society of London (1863) during the period of the American Civil War, in opposition to the Ethnological Society, which had abolitionist sympathies.

What theory is the belief that differences races had evolved independently on each continent?

polygenism

What country did Edward Long and Charles White advocated the belief of polygenism in?

England

What was the profession of Christoph Meiners and Georg Forster?

ethnographers

In what century was polygenism most widespread?

19th century

The Ethnological Society was sympathetic towards what cause?

abolitionist


Today, all humans are classified as belonging to the species Homo sapiens and sub-species Homo sapiens sapiens. However, this is not the first species of homininae: the first species of genus Homo, Homo habilis, are theorized to have evolved in East Africa at least 2 million years ago, and members of this species populated different parts of Africa in a relatively short time. Homo erectus is theorized to have evolved more than 1.8 million years ago, and by 1.5 million years ago had spread throughout Europe and Asia. Virtually all physical anthropologists agree that Archaic Homo sapiens (A group including the possible species H. heidelbergensis, H. rhodesiensis and H. neanderthalensis) evolved out of African Homo erectus ((sensu lato) or Homo ergaster).

What species do all living humans today belong to?

Homo sapiens

When is it theorized that Homo habilis evolved in East Africa?

2 million years ago

How many millions of years ago had Homo erectus spread throughout Europa and Asia?

Members of what species populated parts of Africa in a relatively short time?

Homo habilis

What group might have Archaic Homo sapiens evolve out of?

African Homo erectus


In the early 20th century, many anthropologists accepted and taught the belief that biologically distinct races were isomorphic with distinct linguistic, cultural, and social groups, while popularly applying that belief to the field of eugenics, in conjunction with a practice that is now called scientific racism. After the Nazi eugenics program, racial essentialism lost widespread popularity. Race anthropologists were pressured to acknowledge findings coming from studies of culture and population genetics, and to revise their conclusions about the sources of phenotypic variation. A significant number of modern anthropologists and biologists in the West came to view race as an invalid genetic or biological designation.

Who taught and accepted the belief that biologically distinct races were isomorphic?

many anthropologists

What practice was combined with the field of eugenics regarding the distinctness of social groups?

scientific racism

What effect did the Nazi eugenics program have on racial essentialism?

lost widespread popularity

What conclusions were race anthropologists pressured to revise?

sources of phenotypic variation

What did a lot of modern anthropologists in the West come to view racial designation as?

invalid


Population geneticists have debated whether the concept of population can provide a basis for a new conception of race. In order to do this, a working definition of population must be found. Surprisingly, there is no generally accepted concept of population that biologists use. Although the concept of population is central to ecology, evolutionary biology and conservation biology, most definitions of population rely on qualitative descriptions such as "a group of organisms of the same species occupying a particular space at a particular time" Waples and Gaggiotti identify two broad types of definitions for populations; those that fall into an ecological paradigm, and those that fall into an evolutionary paradigm. Examples of such definitions are:

What type of geneticists have debates about what can provide a basis for a new conception of race?

Population

What class of researchers surprisingly have no generally accepted concept of population?

biologists

What do most definitions of population rely on?

qualitative descriptions

What do Waples and Gaggiotti identify two broad types of?

definitions for populations

What are both ecological and evolutionary definition modifiers of?

paradigm


Traditionally, subspecies are seen as geographically isolated and genetically differentiated populations. That is, "the designation 'subspecies' is used to indicate an objective degree of microevolutionary divergence" One objection to this idea is that it does not specify what degree of differentiation is required. Therefore, any population that is somewhat biologically different could be considered a subspecies, even to the level of a local population. As a result, Templeton has argued that it is necessary to impose a threshold on the level of difference that is required for a population to be designated a subspecies.

What are traditionally geographically isolated?

subspecies

What is "subspecies" used to indicate an objective degree of?

microevolutionary divergence

What is an objection to the idea of subspecies because it doesn't specify this?

degree of differentiation

What would a population have to somewhat be to be considered a subspecies?

biologically different

What did Templeton argue is necessary to impose a threshold on for a population to be a subspecies?

level of difference


This effectively means that populations of organisms must have reached a certain measurable level of difference to be recognised as subspecies. Dean Amadon proposed in 1949 that subspecies would be defined according to the seventy-five percent rule which means that 75% of a population must lie outside 99% of the range of other populations for a given defining morphological character or a set of characters. The seventy-five percent rule still has defenders but other scholars argue that it should be replaced with ninety or ninety-five percent rule.

What must organisms have a measurable level of to be seen as a subspecies?

difference

Who proposed subspecies be defined by the seventy-five percent rule?

Dean Amadon

What year did Dean Amadon make his proposal?

The 75% rule states how much of a population must lie outside the range of other populations for a defining set of characters?

Many scholars argue what should be replaced with a ninety or ninety-five percent rule?

The seventy-five percent rule


In 1978, Sewall Wright suggested that human populations that have long inhabited separated parts of the world should, in general, be considered different subspecies by the usual criterion that most individuals of such populations can be allocated correctly by inspection. Wright argued that it does not require a trained anthropologist to classify an array of Englishmen, West Africans, and Chinese with 100% accuracy by features, skin color, and type of hair despite so much variability within each of these groups that every individual can easily be distinguished from every other. However, it is customary to use the term race rather than subspecies for the major subdivisions of the human species as well as for minor ones.

When did Sewall Wright make his suggestion about human populations?

How should populations long inhabiting separate parts of the world be considered?

different subspecies

What is required to allocate individuals in subspecies populations correctly?

inspection

What did Wright feel it wouldn't take an anthropologist to easily distinguish between of in groups?

individual

What term is it customary to use instead of subspecies?

race


Cladistics is another method of classification. A clade is a taxonomic group of organisms consisting of a single common ancestor and all the descendants of that ancestor. Every creature produced by sexual reproduction has two immediate lineages, one maternal and one paternal. Whereas Carl Linnaeus established a taxonomy of living organisms based on anatomical similarities and differences, cladistics seeks to establish a taxonomy—the phylogenetic tree—based on genetic similarities and differences and tracing the process of acquisition of multiple characteristics by single organisms. Some researchers have tried to clarify the idea of race by equating it to the biological idea of the clade. Often mitochondrial DNA or Y chromosome sequences are used to study ancient human migration paths. These single-locus sources of DNA do not recombine and are inherited from a single parent. Individuals from the various continental groups tend to be more similar to one another than to people from other continents, and tracing either mitochondrial DNA or non-recombinant Y-chromosome DNA explains how people in one place may be largely derived from people in some remote location.

What is cladistics a method of?

classification

What is a clade a taxonomic group of?

organisms

How many common ancestors does a clade have?

single

What is another term for a phylogenetic tree?

taxonomy

Which chromosome sequences are used to study ancient human migration paths?

Y