A pecten (plural pectens or pectines) is a

comb A comb is a tool consisting of a shaft that holds a row of teeth for pulling through the hair to clean, untangle, or style it. Combs have been used since prehistoric times, having been discovered in very refined forms from settlements dating ba ...

-like structure, widely found in the biological world. Although pectens in various animals look similar, they have a varied range of uses, from grooming and filtering to

sensory adaptation Neural adaptation or sensory adaptation is a gradual decrease over time in the responsiveness of the sensory system to a constant stimulus. It is usually experienced as a change in the stimulus. For example, if a hand is rested on a table, the ta ...

Etymology

The adjective, pectinate, means supplied with a comb-like structure. This form, cognate to pecten with both derived from the Latin for comb, ''pectin'' (genitive ''pectinis''), is reflected in numerous

scientific names In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

in forms such as pectinata, pectinatus or pectinatum, or in specific

epithets An epithet (, ), also byname, is a descriptive term (word or phrase) known for accompanying or occurring in place of a name and having entered common usage. It has various shades of meaning when applied to seemingly real or fictitious people, di ...

such as ''

Murex pecten The Venus comb murex, scientific name ''Murex pecten'', is a species of large predatory sea snail, a marine gastropod mollusk in the family Muricidae, the rock snails or murex snails. The shell of this Indo-Pacific species has a very long ...

''. Some

toothcomb A toothcomb (also tooth comb or dental comb) is a dental structure found in some mammals, comprising a group of front teeth arranged in a manner that facilitates grooming, similar to a hair comb. The toothcomb occurs in lemuriform primates ( ...

s are referred to as pectinations.

Oral use

In ducks, they exist on the sides of the

bill Bill(s) may refer to: Common meanings * Banknote, paper cash (especially in the United States) * Bill (law), a proposed law put before a legislature * Invoice, commercial document issued by a seller to a buyer * Bill, a bird or animal's beak Plac ...

and serve both as a strainer for food and a comb for preening.

Whales Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. As an informal and colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart from dolphins and ...

have a similar oral comb-like structure called

baleen Baleen is a filter-feeding system inside the mouths of baleen whales. To use baleen, the whale first opens its mouth underwater to take in water. The whale then pushes the water out, and animals such as krill are filtered by the baleen and ...

Retinal use

The avian eye also contains a structure called a

pecten oculi The pecten or pecten oculi is a comb-like structure of blood vessels belonging to the choroid in the eye of a bird. It is a non- sensory, pigmented structure that projects into the vitreous humor from the point where the optic nerve enters the ...

, which is a comb-like projection of the

retina The retina (from la, rete "net") is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs. The optics of the eye create a focused two-dimensional image of the visual world on the retina, which then ...

. It is thought to enhance nutrition for the cells of the retina.

Sensory use

They also occur on the underside of

scorpion Scorpions are predatory arachnids of the order Scorpiones. They have eight legs, and are easily recognized by a pair of grasping pincers and a narrow, segmented tail, often carried in a characteristic forward curve over the back and always end ...

s, where they are used as sensory organs.

References

Birds Sensory receptors {{animal-anatomy-stub