Vibrissae grow in various places on most mammals, including all primates except humans. Vibrissae are analogous to antennae found on insects and other arthropods. In medicine, the term vibrissae also refers to the thick hairs found inside human nostrils.
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Blind ringed seals have even been observed successfully hunting on their own in Lake Saimaa, likely relying on their vibrissae to gain sensory information and catch prey. Unlike terrestrial mammals, such as rodents, pinnipeds do not move their vibrissae over an object when examining it but instead extend their moveable whiskers and keep them in the same position. By holding their vibrissae steady, pinnipeds are able to maximize their detection ability. The vibrissae of phocids are undulated and wavy while otariid and walrus vibrissae are smooth.
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Unlike terrestrial mammals, such as rodents, pinnipeds do not move their vibrissae over an object when examining it but instead extend their moveable whiskers and keep them in the same position. By holding their vibrissae steady, pinnipeds are able to maximize their detection ability. The vibrissae of seals are undulated and wavy while sea lion and walrus vibrissae are smooth. Research is ongoing to determine the function, if any, of these shapes on detection ability.
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The ear pinnae are long and conspicuous, and naked of dark fur at the tips in older animals. The mystacial vibrissae can be very long, and regularly extend beyond the ears. Adults have all white vibrissae, juveniles and subadults have a mixture of white and black vibrissae, including some that have dark bases and white ends, and pups and yearlings have all black vibrissae. The eyes are proportionately large and conspicuous, especially on females, subadults, and juveniles.
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Unlike most members of the family Canidae, foxes have partially retractable claws. Fox vibrissae, or whiskers, are black. The whiskers on the muzzle, mystaciae vibrissae, average long, while the whiskers everywhere else on the head average to be shorter in length. Whiskers (carpal vibrissae) are also on the forelimbs and average long, pointing downward and backward.
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For hunting the rodents rely on their vibrissae (whiskers) to help locate prey along the streams edge. The vibrissae contain a very sensitive and developed trigeminal nerve that runs along the infraorbital foramen.
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The structure of the brain region (barrel cortex) which receives information from the vibrissae is similar to that found in the visual cortex which permits the cat to create a three-dimensional map of its surroundings. This does not mean that sensing with vibrissae is a type of vision. It is still a touch sensation and environmental information is built up incrementally (in small steps). Vibrissae aid sensation and navigation.
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Patagonian fox showing four major cranial groups of vibrissae: supraorbital (above the eye), mystacial (where a moustache would be), genal (on the cheek, far left), and mandibular (pointing down, under the snout). A pet rat clearly showing the grid-like arrangement of the macrovibrissae on the face, and the microvibrissae under the nostrils. The supraorbital vibrissae above the right eye are also visible.All the hairs of the manatee may be vibrissae.
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A dog's whiskers act as sensing organs. The main difference between human and dog touch is the presence of specialized whiskers known as vibrissae. Vibrissae are present above the dog's eyes, below their jaw, and on their muzzle. They are sophisticated sensing organs.
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Anurognathid pterosaurs had a rugose (wrinkled) jaw texture that has been interpreted as the attachment sites for vibrissae,Bennett et al 2007b though actual vibrissae have not been recorded. More recently, a specific type of pycnofibers/feathers has been found around anurognathid mouths.
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Mice can sense surfaces and air movements with their whiskers which are also used during thigmotaxis. If mice are blind from birth, super-normal growth of the vibrissae occurs presumably as a compensatory response. Conversely, if the vibrissae are absent, the use of vision is intensified.
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Surrounding the tusks is a broad mat of stiff bristles ("mystacial vibrissae"), giving the walrus a characteristic whiskered appearance. There can be 400 to 700 vibrissae in 13 to 15 rows reaching 30 cm (12 in) in length, though in the wild they are often worn to much shorter lengths due to constant use in foraging. The vibrissae are attached to muscles and are supplied with blood and nerves, making them highly sensitive organs capable of differentiating shapes thick and wide.
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Using their vibrissae they are able to detect sound and pressure waves in their otherwise dark environment.markka coin.
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As previously described in the methods section, we examined two patterns of vibrissae movement: rhythmic whisking and fan-like divarication.
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Research is ongoing to determine the function, if any, of these shapes on detection ability. The vibrissa's angle relative to the flow, not the shape, however, seems to be the most important factor. The vibrissae of some otariids grow quite long—those of the Antarctic fur seal can reach . Walruses have the most vibrissae, at 600–700 individual hairs.
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Many land mammals, for example rats and hamsters, have an arrangement of cranial (of the skull) vibrissae that includes the supraorbital (above the eyes), genal (of the cheeks), and mystacial (where a moustache would be) vibrissae, as well as mandibular (of the jaw) vibrissae under the snout. These groups, all of which are visible in the accompanying image of the Patagonian fox, are well conserved across land mammals though anatomical and functional details vary with the animal's lifestyle. Mystacial vibrissae are generally described as being further divided into two sub-groups: the large macrovibrissae that protrude to the sides and the small microvibrissae below the nostrils that mostly point downwards. Most simply described, macrovibrissae are large, motile and used for spatial sensing, whereas microvibrissae are small, immotile and used for object identification.
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19; Tirira, 2007, p. 170 It has a long snout and small, dark ears that appear hairless. The vibrissae (whiskers) are long.Tirira, 2007, p.
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The body of sirenians is sparsely covered in short hair (vibrissae), except for on the muzzle, which may allow for tactile interpretation of their environment.
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Macrovibrissae and supraorbital vibrissae of Phoca vitulina. A chinchilla with large macrovibrissae. Whiskers or vibrissae (; singular: vibrissa; ) are a type of mammalian hair that are typically characterised, anatomically, by their long length, large and well-innervated hair follicle, and by having an identifiable representation in the somatosensory cortex of the brain. They are specialised for tactile sensing (other types of hair operate as more crude tactile sensors).
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Generally, vibrissae are considered to mediate a tactile sense, complementary to that of skin. This is presumed to be advantageous in particular to animals that cannot always rely on sight to navigate or to find food, for example, nocturnal animals or animals which forage in muddy waters. Sensory function aside, movements of the vibrissae may also indicate something of the state of mind of the animal, and the whiskers play a role in social behaviour of rats. The sensory function of vibrissae is an active research area—experiments to establish the capabilities of whiskers use a variety of techniques, including temporary deprivation either of the whisker sense or of other senses.
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This is likely an adaptation for living in marine coastal habitats. Sea lions have fairly acute underwater hearing, with a hearing range of 0.4–32 kHz. Sea lions rely on their whiskers or vibrissae for touch and detection of vibrations underwater. Compared to the harbor seal, the California sea lion's vibrissae are smoother and less specialized and thus perform less when following hydrodynamic trails, although they still perform well.
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1581 (2011): 3077-84. . . When used for touch, these vibrissae are moved to the forward position and kept still while the head moves, thus moving the vibrissae on the surface of an object. This is in contrast to rodents, which move the whiskers themselves to explore objects. More recently, research has been done to see if pinnipeds can use these same whiskers to detect hydrodynamic stimuli in addition to tactile stimuli.
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Tail is feather-shaped and reddish brown with a blackish undersurface. Membrane behind hind limb is small. Vibrissae is black. Dorsal fur is very soft, long and sheen.
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Rats do not depend upon visual cues like some of the other species tested. Their nocturnal habits lead them to seek food largely by smell. When moving about in the dark, they respond to tactual cues from their stiff whiskers (vibrissae) located on the snout. Hooded rats tested on the visual cliff show little preference for either side of the visual cliff apparatus as long as they could feel the glass with their vibrissae.
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When seals swim with their vibrissae projected forward, the flattened, undulated structure prevents the vibrissae from bending backward or vibrating to produce water disturbances. Thus, the seal prevents noise from the whiskers by a unique whisker structure. However, sea lions appear to monitor modulations of the characteristic frequency of the whiskers to obtain information about hydrodynamic stimuli. This different mechanism might be responsible for the sea lion's worse performance in tracking an aging hydrodynamic trail.
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Vibrissae are absent. The wing is clear or with conspicuous markings. The costa is continuous and the subcosta is complete. Crossvein BM-Cu is present and the anal cell (cell cup) is closed.
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Baleen whales split from toothed whales around 34 million years ago. The smallest cetacean is Maui's dolphin, at and ; the largest is the blue whale, at and . Baleen whales have a tactile system in the short hairs (vibrissae) around their mouth; toothed whales also develop vibrissae, but lose them during fetal development or shortly after birth, leaving behind electroreceptive vibrissal crypts in some species. Cetaceans have well-developed senses—their eyesight and hearing are adapted for both air and water.
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Vibrissae (derived from the Latin "vibrio" meaning to vibrate) typically grow in groups in different locations on an animal. These groups are relatively well conserved across land mammals, and somewhat less well conserved between land and marine mammals (though commonalities are certainly present). Species-specific differences are also found. Vibrissae of different groups may vary in their anatomical parameters and in their operation, and it is generally assumed that they serve different purposes in accordance with their different locations on the body.
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The presence of mystacial vibrissae in distinct lineages (Rodentia, Afrotheria, marsupials) with remarkable conservation of operation suggests that they may be an old feature present in a common ancestor of all therian mammals. Indeed, some humans even still develop vestigial vibrissal muscles in the upper lip, consistent with the hypothesis that previous members of the human lineage had mystacial vibrissae. Thus, it is possible that the development of the whisker sensory system played an important role in mammalian development, more generally.
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Ocelli may be present or absent (Conopinae). Ocellar bristles are small or absent. Interfrontal bristles and vibrissae are absent. The antennae have three segments, the third bearing a dorsal bare arista or terminal style.
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Vibrissae are absent and the postvertical bristles are divergent or absent. Up to three pairs of frontal bristles curve forward or backward. Interfrontal bristles are absent. The wings are clear or have a smoky pattern.
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The fossa has a large, prominent rhinarium similar to that of viverrids, but has comparatively larger, round ears, almost as large as those of a similarly sized felid. Its facial vibrissae (whiskers) are long, with the longest being longer than its head. Like some mongoose genera, particularly Galidia (which is now in the fossa's own family, Eupleridae) and Herpestes (of Herpestidae), it has carpal vibrissae as well. Its claws are retractile, but unlike those of Felidae species, they are not hidden in skin sheaths.
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They have ocelli with ocellar bristles. Vibrissae and palpi are poorly developed. The front legs of the male often have extrusions, spurs, teeth, or other ornamentation. The tibia has a dorsal preapical bristle in most genera.
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Their pelts are thick and course with guard hairs measuring up to 30 mm. Additionally they have vibrissae that provide tactile feedback located above the eyes, under the chin, along the back and sides, on the abdomen and on the fore- and hind limbs. These vibrissae, or whiskers, measure 90 mm long on the snout, and 70 mm elsewhere. Other noted features include: the Jacobsen's organ which is as a specialized olfactory structure, a compartmentalized stomach into nonglandular cranial and glandular caudal sections, and a vertebral column that is convex from neck to tail.
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The fur growing process starts at the snout and proceeds back through the body, although the tail attains fur before the rump, which is the last part of the body to become covered. Just before the start of the furring process, the colour of the bare devil's skin will darken and become black or dark grey in the tail. The devils have a complete set of facial vibrissae and ulnar carpels, although it is devoid of anconeal vibrissae. During the third week, the mystacials and ulnarcarpals are the first to form.
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Weksler, 2006, figs. 34–39 Later in the same year, he, together with Alexandre Percequillo and Robert Voss, named ten new genera for species previously placed in Oryzomys, including Transandinomys, which has Oryzomys talamancae (now Transandinomys talamancae) as its type species. They also included Oryzomys bolivaris, which was not included in Weksler's phylogenetic study, in this new genus. The two species are morphologically similar, but Weksler and colleagues could identify only one synapomorphy (shared-derived trait) for them: very long superciliary vibrissae (vibrissae, or whiskers, above the eyes).
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Ocelli and ocellar bristles are present. The postvertical bristles are parallel or converge. The two pairs of frontal bristles curve outward and scattered interfrontal setulae are present. Vibrissae are absent, but strong bristles occur near the vibrissal angle.
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These are important for detecting their prey on the muddy sea floor. In addition to foraging, vibrissae may also play a role in navigation; spotted seals appear to use them to detect breathing holes in the ice.Riedman, p. 42.
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Scattered interfrontal setulae are present Ocellar bristles are present. Postvertical bristles are absent (rarely present). Vibrissae absent but Geomyza with a strong bristle near the vibrissal angle. Ocelli are present and the arista is pubescent or with long hairs.
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Grzimek, Bernhard. Grzimek's Animal Life Encyclopedia, Volume 10: Mammals I. New York: Van Nostrand Reinhold Company, 1975. Print. Talpids rely primarily on their sense of touch, having sensory vibrissae on their faces, legs, and tails. Their flexible snouts are particularly sensitive.
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These two sub-groups can be identified in the accompanying image of the rat, but it can also be seen that there is no clear physical boundary between them. This difficulty in delineating the sub-groups visually is reflected by similarly weak boundaries between them in anatomical and functional parameters, though the distinction is nonetheless referred to ubiquitously in scientific literature and is considered useful in analysis. Apart from cranial vibrissae, other groups are found elsewhere on the body. Many land mammals, including domestic cats, also have carpal (of the wrist) vibrissae on the underside of the leg just above the paws.
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Interfrontal bristles are absent or present. Peristomal bristles ("false vibrissae") are present. In the more common Anthomyza and Paranthomyza, the lower side of femur 1 has a well-developed spine in apical third. Wings are usually long and narrow and immaculate (sometimes marked).
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Natural shapes of rat's mystacial pad vibrissae (whiskers) are well approximated by pieces of the Euler spiral. When all these pieces for a single rat are assembled together, they span an interval extending from one coiled domain of the Euler spiral to the other.
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The muzzle has long coarse vibrissae on either side. Its eyes are located toward the front of the head. The small ears are oval-shaped with an inconspicuous tragus and antitragus. Its paws are narrow with short digits that are webbed to the last joint.
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Nocturnal species often have enlarged eyes and some are sensitive to ultraviolet light. Many species have long, sensitive whiskers or vibrissae for touch or "whisking". Some rodents have cheek pouches, which may be lined with fur. These can be turned inside out for cleaning.
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The tail is dark brown above and lighter below and the ears and feet are long. The vibrissae (whiskers) are very long. In the skull, the rostrum (front part) is long and the braincase is low. The number of chromosomes varies from 34 to 54.
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The upper head between the muzzle and ears is usually darker gray-brown. The tail may be more rufous than the back. The summer fur is gray to gray-brown with some light yellow. The lips are white and the chin has grayish-brown vibrissae.
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The mystacial vibrissae (whiskers on the upper lip) are long, usually extending a little beyond the ears when laid back against the head, but the superciliary vibrissae (whiskers above the eyes) are short and do not extend beyond the ears. The upper surface on the forefeet is covered with brown fur, and there is white or silvery fur on the digits. Ungual tufts (fur around the bases of the claws) are present on the second through fourth digits. On the short, fairly broad hindfeet, the upper side is covered densely with silvery to white hairs near the tips of the feet and toes, and with brown fur otherwise.
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Whilst these five major groups (supraorbital, genal, mystacial, mandibular, carpal) are often reported in studies of land mammals, several other groups have been reported more occasionally (for instance, see ). Marine mammals can have substantially different vibrissal arrangements. For instance, cetaceans have lost the vibrissae around the snout and gained vibrissae around their blowholes, whereas every single one of the body hairs of the Florida manatee (see image) may be a vibrissa. Other marine mammals (such as seals and sea-lions) have cranial vibrissal groups that appear to correspond closely to those described for land mammals (see the accompanying image of a seal), although these groups function quite differently.
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The use of this laryngeal call and vibrissae allow the shrews to find their way around their environment. There have not been any concrete reports on the modes of communication used by this species, however, vocalization and tactile and chemical cues are likely to be used.
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The other species of quoll have also been known to eat carrion. The paws and vibrissae of quolls allow them to reach into small burrows to find prey. Quolls hunt by stalking. Depending on the size of its prey, a quoll may leap or pounce on it.
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Vibrissae are always absent. Up to two pairs of frontal bristles and scattered interfrontal setulae are present. The costa is interrupted at some distance from R1 and only the basal part of the subcosta is developed. The vein bordering the anal cell is straight on the outer side.
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Vibrissae are well developed. On the mesonotum there are two pairs of dorsocentral bristles. The costa is interrupted near the subcosta (which reaches the costa). The posterior basal wing cell and discoidal wing cell are fused and the anal vein does not reach the margin of the wings.
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The docodont Castorocauda, further removed from crown group mammals than Hadrocodium, had two layers of fur, guard hairs and underfur, as do mammals today. It is possible that early mammaliaforms had vibrissae; Tritheledontidae, a group of Cynodonts, probably had whiskers. A common ancestor of all therian mammals did so.
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True vibrissae are absent, but several genera have strong bristles near the vibrissal angle. The wings usually have yellow, brown, or black markings or are dark-coloured with lighter markings. In a few species, the wings are clear. The costa has both a humeral and a subcostal break.
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Recognizing that the array was similar to that of the vibrissae (whiskers) on the mystacial pad (region where whiskers grow from) of certain mammals, they hypothesized that the barrels were the "cortical correlates of the mystacial vibrissae" and that "one barrel represents one vibrissa". Whereas small non-whisker areas of barrel cortex correspond to large and sometimes overlapping areas of the body, each much larger whisker barrel corresponds to a single whisker. As a result, the whisker barrels are the focus of the majority of barrel cortex research, and 'barrel cortex' is often used to refer primarily to the whisker barrels. Consequently, much of this article focuses on rodent whisker barrel cortex.
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The barrels that correspond to the major facial whiskers (mystacial vibrissae) are contained within the posteromedial barrel subfield (PMBSF). The barrels here are the largest and most elliptical in shape and have a striking topographical organization that is identical to that of the whiskers; they are organized into 5 rows of 4-7 large whiskers that run close to parallel with the bridge of the nose.Woolsey & Van der Loos, 1970 The organisation of the mystacial vibrissae and corresponding barrels is so consistent that there is a naming convention to identify each whisker in rats and mice. Rows are designated A to E from top to bottom, and columns of whiskers within each row are numbered from back to front.
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Natural shapes of rat's mystacial pad vibrissae are well approximated by pieces of the Euler spiral. When all these pieces for a single rat are assembled together, they span an interval extending from one coiled domain of the Euler spiral to the other. Rats and mice are considered to be "whisker specialists", but marine mammals may make even greater investment in their vibrissal sensory system. Seal whiskers, which are similarly arrayed across the mystacial region, are each served by around 10 times as many nerve fibres as those in rats and mice, so that the total number of nerve cells innervating the mystacial vibrissae of a seal has been estimated to be in excess of 300,000.
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Sensitive vibrissae and forepaws enable sea otters to find prey (like this purple sea urchin) using their sense of touch. The sea otter is diurnal. It has a period of foraging and eating in the morning, starting about an hour before sunrise, then rests or sleeps in mid-day.Love, pp.
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At birth, the North American river otters are fully furred, blind, and toothless. The claws are well-formed and facial vibrissae (about long) are present. The kits open their eyes after 30–38 days. The newborns start playing at five to six weeks, and begin consuming solid food at 9–10 weeks.
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It is silky, extremely soft, and firmly adhered to the skin. Up to 75 hairs, in diameter, emerge together from a single hair follicle. Vibrissae (whiskers) are abundant, strong, and long——and emerge from single follicles. The general color of their upper parts is bluish or silvery gray; the underparts are yellowish-white.
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Judging from the properties of its talus, Azibius was probably an arboreal quadruped, capable of leaping and climbing in trees, very similar to living cheirogaleid lemurs. Based on what can be inferred from the maxillary remains, Azibius is thought to have had large eyes and extra vibrissae, which suggests it was nocturnal.
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Aside from the vibrissae, the walrus is sparsely covered with fur and appears bald. Its skin is highly wrinkled and thick, up to around the neck and shoulders of males. The blubber layer beneath is up to thick. Young walruses are deep brown and grow paler and more cinnamon-colored as they age.
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"Fox squirrels also have several sets of vibrissae, hairs or whiskers that are used as touch receptors to sense the environment. These are found above and below their eyes, on their chin and nose, and on each forearm." The dental formula of S. niger is . Fox squirrel foraging in the grass in Indianapolis, Indiana.
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Cats, like rats, are nocturnal animals, sensitive to tactual cues from their vibrissae. But the cat, as a predator, must rely more on its sight. Kittens were observed to have excellent depth- discrimination. At four weeks, the earliest age that a kitten can skillfully move about, they preferred the shallow side of the cliff.
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The two species are morphologically similar, but they could identify only one synapomorphy (shared-derived trait) for them: very long superciliary vibrissae (whiskers above the eyes).Weksler et al., 2006, p. 26 Transandinomys is one of about 30 genera in Oryzomyini, a diverse assemblage of American rodents of over a hundred species,Weksler, 2006, p.
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The little spotted kiwi has a length of and the weight of the male is and the female weighs , making it the smallest species of kiwi. Their feathers are pale-mottled grey, with fine white mottling, and are shaggy looking.BirdLife International (2008a) They lack aftershafts and barbules. They have large vibrissae feathers around the gape.
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Xerus rutilus is a member of the Xerini tribe, but differs from its sister group Xerus daamsi. Both are separate and distinct from the North African equivalent Atlantoxerus. Vibrissae (whiskers) length and brain size are both smaller than arboreal squirrels of the region, but are similar to other terrestrial squirrels. No significant sexual dimorphism is noted in X. rutilus.
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For terms see Morphology of Diptera They are medium-sized or relatively small flies, they have spots on their wings (dark smoky apical spot in Palloptera ustulata). The wings are considerably longer than the abdomen. The head is semispherical and the postvertical bristles on the head are parallel or divergent. Vibrissae on the head are absent.
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To aid with navigation and sensation, cats have dozens of movable whiskers (vibrissae) over their body, especially their faces. These provide information on the width of gaps and on the location of objects in the dark, both by touching objects directly and by sensing air currents; they also trigger protective blink reflexes to protect the eyes from damage.
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P. velox is a nocturnal predator, hunting primarily by touch and scent in and around calm pools. Each dive lasts only seconds. P. velox searches both within the pool and along the bank for prey using the sensitive vibrissae and odor and apparently not eyesight. It prefers areas that have cover to retreat to when it feels threatened.
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Thomasomys ucucha is a medium-sized Thomasomys with a relatively long tail. The dense, fine, and soft fur is dark brown on the upperparts, changing gradually into the grey underparts. The mystacial vibrissae (whiskers above the mouth) are long and extend beyond the ears when laid back against the head. Sparse short, dark hairs are present on the ears.
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There are three or four pairs of orbital bristles on the head directed outward (inset upswept). Postvertical bristles are absent but diverging pseudopostocellar bristles are present. Other head bristles present are ocellar bristles, 2-5 pairs of frontal bristles, curving outward, interfrontal bristles and vibrissae ("whiskers"). The genae are high with 1 or more upcurving bristles.
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The vibrissae on head are well developed. The arista has long rays above and shorter rays below. There are two pairs of dorsocentral bristles on thorax and one mesopleural bristle on the side of the thorax. Costa interrupted near R1, Subcosta reduced and close to R1, posterior basal wing cell and discoidal wing cell fused; anal wing cell rudimentary.
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Interfrontal bristles may be present as may scattered interfrontal setulae. Vibrissae may be absent or present. On the mesonotum are one to two pairs of dorsocentral bristles. The costa is entire, without interruptions; the subcosta is reduced; posterior basal wing cell and discoidal wing cell are fused; anal cell of wing and anal vein of wing are absent.
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Pinnipeds, including sea lions and seals, use their mystacial vibrissae (whiskers) for active touch, including size and shape discrimination, and texture discrimination in seals.Miersch, L, W Hanke, S Wieskotten, F D Hanke, J Oeffner, A Leder, M Brede, M Witte, and G Dehnhardt. “Flow sensing by pinniped whiskers.” Philosophical Transactions of the Royal Society of London B 366, no.
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However, a more recent study shows that the morphology of the seal's vibrissae actually prevents vortices produced by the whiskers from creating excessive water disturbances.Hanke, W, M Witte, L Miersch, M Brede, J Oeffner, M Michael, F Hanke, A Leder, and G Dehnhardt. “Harbor seal vibrissa morphology suppresses vortex-induced vibrations.” Journal of Experimental Biology 213, no.
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A yawning cat shows how the mystacial macrovibrissae can be swept forward. The follicles of some groups of vibrissae in some species are motile. Generally, the supraorbital, genal and macrovibrissae are motile, whereas the microvibrissae are not. This is reflected in anatomical reports that have identified musculature associated with the macrovibrissae that is absent for the microvibrissae.
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Pinnipeds have well-developed tactile senses. Their mystacial vibrissae have ten times the innervation of terrestrial mammals, allowing them to effectively detect vibrations in the water. These vibrations are generated, for example, when a fish swims through water. Detecting vibrations is useful when the animals are foraging and may add to or even replace vision, particularly in darkness.
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To find whether seals could actually follow hydrodynamic stimuli using their vibrissae rather than just detect them, a blindfolded harbor seal with headphones can be released into a tank in which a toy submarine has left a hydrodynamic trail. After protracting its vibrissae to the most forward position and making lateral head movements, the seal can locate and follow a trail of 40 meters even when sharp turns to the trail are added. When whisker movements are prevented with a mask covering the muzzle, the seal cannot locate and follow the trail, indicating use of information obtained by the whiskers. Trails produced by live animals are more complex than that produced by a toy submarine, so the ability of seals to follow trails produced by other seals can also be tested.
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It is of medium size, with a head and body length of , with a long tail 81–94% of the head and body length. Its head is long and pointed, with numerous long vibrissae up to in length. Its dorsal pelage is blackish brown, gradually fading into dusky brown on venter. Its body hairs are fairly uniformly coloured from base to tip.
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It is of small size, its head and body length of , tail , of which the proximal are sparsely covered by longer bristles, hindfoot with claw and without claw. Its head is short and pointed, with sparse vibrissae up to in length. Its dorsal and ventral pelage is dark brown. Its hairs are on dorsum and on mid-venter in length.
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African Pygmy Squirrels have keen hearing, vision, and smell. They use the vibrissae on their bodies to help them in navigation of tree trunks and branches. A low-intensity alarm vocalization has been recorded and it is described as a “faint pipping sound,” seeming to alert and call attention to nearby danger. These calls may warn young or nearby animals of a threat.
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The prelambrum protrudes from the oral cavity. Vibrissae are absent and the postvertical bristles are divergent.Shtakel'berg, A.A. Family Driomyzidae in Bei-Bienko, G. Ya, 1988 Keys to the insects of the European Part of the USSR Volume 5 (Diptera) Part 2 English edition. The roughly 22 species are placed in 6 genera (with two additional genera known only as fossils).
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For terms see Morphology of Diptera Minute flies with grey or brown-grey body and, usually, maculate wings. The postvertical bristles on head are cruciate and vibrissae are present on the head are present. The front orbital bristles are inset and upswept. The costa is interrupted near the end of Radial vein 1 and sometimes also near the humeral crossvein.
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The longer guard hairs, which are most common towards the middle of the back, are completely black. The fur of the underparts appears dark gray and is not sharply demarcated from the upperparts. There, the hairs are also plumbeous at the bases, but the tips range from white to yellowish-brown. The mystacial vibrissae—whiskers above the mouth—are medium-sized.
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Drawing of dissected specimen, with exposed muscles and wing-claw It has no preen gland, and its feathers have no aftershafts and no barbules. There are large vibrissae around its gape, and it has no tail, only a pygostyle. It has a length of and the female weighs and the male weighs . Its bill is long and slender with a slight down-curve.
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Juvenile eastern gray squirrel developing fur Newborn gray squirrels weigh 13–18 grams and are entirely hairless and pink, although vibrissae are present at birth. 7–10 days postpartum, the skin begins to darken, just before the juvenile pelage grows in. Lower incisors erupt 19–21 days postpartum, while upper incisors erupt after 4 weeks. Cheek teeth erupt during week 6.
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Like other canids, it has 42 teeth with the dental formula . The maned wolf's rhinarium extends to the upper lip, similar to the bush dog, but its vibrissae are longer. The skull also features a prominent sagittal crest. The maned wolf's footprints are similar to those of the dog, but have disproportionately small plantar pads when compared to the well-opened digit marks.
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Systems that detect hydrodynamic stimuli are also used for sensing other stimuli. For example, sensory hairs are also used for the tactile sense, detecting objects and organisms up close rather than via water disturbances from afar.Dehnhardt, G, and A. Kaminski. “Sensitivity of the mystacial vibrissae of harbour seals (Phoca vitulina) for size differences of actively touched objects.” Journal of Experimental Biology 198, no.
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A large part of the brain of whisker- specialist mammals is involved in the processing of nerve impulses from vibrissae, a fact that presumably corresponds to the important position the sense occupies for the animal. Information from the vibrissae arrives in the brain via the trigeminal nerve and is delivered first into the trigeminal sensory complex of brainstem. From there, the most studied pathways are those leading up through parts of thalamus and into barrel cortex, though other major pathways through the superior colliculus in midbrain (a major visual structure in visual animals) and the cerebellum, to name but a couple, are increasingly coming under scrutiny. Neuroscientists, and other researchers, studying sensory systems favour the whisker system for a number of reasons (see Barrel cortex), not least the simple fact that laboratory rats and mice are whisker, rather than visual, specialists.
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Its vibrissae (whiskers) are long and thick, enhancing sensory perception underwater and on land. The fur of the species is short (guard hairs average ), with a density of about 57,800 hairs/cm2 (373,000 hairs/in2) in the midback section. The pelage has a high luster and varies from light brown to black. The throat, chin, and lips are grayer than the rest of the body.
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With no constraints on weight due to flight requirements, brown kiwi females carry and lay a single egg that may weigh as much as . Like most other ratites, they have no uropygial gland (preen gland). Their bill is long, pliable and sensitive to touch, and their eyes have a reduced pecten. Their feathers lack barbules and aftershafts, and they have large vibrissae around the gape.
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Common mole-rats are endothermic, having the ability to generate their own heat and keep their body temperature above ambient temperature. In arid environments they have lower individual body masses; this reduces their need for food and improves energy conservation. These mole-rats also have long sensory hairs called vibrissae that stand out from the pelage (fur covering) over their body and hind legs.
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When these quills are vibrated, they produce a hiss-like rattle. The front feet of the crested porcupine have four developed and clawed digits with a regressed thumb, the rear feet have five. The paws have naked and padded soles and have a plantigrade gait. The ears are external and both the eyes and ears are very small with long vibrissae on its head.
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Also, elephant seals have the ability to fast for long periods of time while breeding or molting. The turbinate process, another unique adaptation, is very beneficial when these seals are fasting, breeding, molting, or hauling out. This unique nasal structure recycles moisture when they breathe and helps prevent water loss. Elephant seals have external whiskers called vibrissae to help them locate prey and navigate their environment.
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They have large vibrissae around the gape, and they have no tail, only a small pygostyle. The common name of this bird comes from black spots on its feathers. They use their powerful legs and claws for defence against predators like stoats or ferrets. Kiwis are flightless birds, and hence lack hollow bones, lack a keel to which wing muscles anchor, and have tiny wings.
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The golden palm civet is brown on the upper side, but individually variable from dark sepia to ochreous, rusty or golden-brown. The tips of the contour hairs are frequently lustrous, sometimes greyish. The legs are about the same tint as the back, but the tail and the face are sometimes noticeably paler, buffy-grey. The face does not have a pattern, and the vibrissae are dirty white.
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Rictal bristles are found around the eyes and bill. They may serve a similar purpose to eyelashes and vibrissae in mammals. Although there is as yet no clear evidence, it has been suggested that rictal bristles have sensory functions and may help insectivorous birds to capture prey. In one study, willow flycatchers (Empidonax traillii) were found to catch insects equally well before and after removal of the rictal bristles.
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Subsequently, the infraorbital, interramal, supraorbital and submental vibrissae form. The last four typically occur between the 26th and 39th day. alt=A view from directly above three devils lying with bodies almost touching, on dry leaves, dirt and rocks, under bright sunshine. Their eyes open shortly after their fur coat develops—between 87 and 93 days—and their mouths can relax their hold of the nipple at 100 days.
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While not well studied, the Rakali (Australian water rat) may also be able to detect water movements with its vibrissae as these have a large amount of innervation, though further behavioral studies are needed to confirm this. While tying the presence of whiskers to hydrodynamic reception has allowed the list of mammals with this special sense to grow, more research still needs to be done on the specific neural circuits involved.
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Whiskers (vibrissae) of captive walrus (Japan) Reportedly an ethnic trait of Celts and Gauls, the walrus moustache enjoyed immense popularity among men in the latter part of the 19th and early years of the 20th centuries. Gentlemen ranging from scientists to philosophers to politicians often favored the rugged look that the style created. After falling out of favor in the 1920s it enjoyed a temporary resurgence during the youth counterculture revolution of the 1960s.
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The dorsal coloration is slightly darker around the neck and crown. The hair on the throat, cheeks, and ears is white or off-white and also less dense, allowing the dark skin underneath to show through. The muzzle is dark grayish and the nose is black, and the eyes are encompassed by black triangular patches. Facial vibrissae (whiskers) are developed and found above the lips (mystacal), on the cheeks (genal), and on the eyebrow (superciliary).
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This fur seal is a midsized pinniped with a relatively long neck and pointed muzzle compared with others in the family. The nose does not extend much past the mouth, the external ears are long, prominent, and naked at the tip. Adults have very long vibrissae, particularly males, up to 35 to 50 cm. The fore flippers are about one-third, and hind flippers slightly more than one-fourth, of the total length.
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The Sambirano mouse lemur (Microcebus sambiranensis) is a small, recently discovered primate and like the other mouse lemurs can only be found on the island of Madagascar. The dorsal side is both cinnamon and rufous-cinnamon and is grey ventrally. It has vibrissae that are dark in color. The species was discovered in northwestern Madagascar, in the Ankarana Special Reserve, where vegetation remains dense, after a survey was completed of the area.
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Captive Asian small-clawed otters were observed to leave shellfish in the sun so that the heat causes them to open. That way, they consume the meat without having to crush the shells. The hindmost upper teeth (pm4 and m3) are broad and robust and are specialized for crushing the exoskeletons of crabs and other hard shelled prey. They hunt food by using their vibrissae to detect movements of prey in the water.
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Both hair and vibrissae may be removed. Barbering is more frequently seen in female mice; male mice are more likely to display dominance through fighting. C57BL/6 has several unusual characteristics which make it useful for some research studies but inappropriate for others: It is unusually sensitive to pain and to cold, and analgesic medications are less effective in this strain. Unlike most laboratory mouse strains, the C57BL/6 drinks alcoholic beverages voluntarily.
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It is a medium-sized rice rat distinguished by its very long vibrissae (whiskers)—those above the eyes are up to long. The fur, which is soft and dense, is usually dark brown above and light gray below; it is darker in juveniles. The feet are long and the tail is about as long as the head and body. The skull is narrow and has a broad interorbital region (between the eyes).
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More recently, studies on hydrodynamic detection in the California sea lion (Zalophus californianus) have been done. Despite the structure of their mystacial vibrissae, different from those of seals, these sea lions can detect and follow a trail made by a small toy submarine. Sea lions use an undulatory pattern of tracking similar to that in seals, but do not perform as well with increased delay before they are allowed to swim and locate the trail.
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Similar to the vibrissae of seals and sea lions, Florida manatees also use hairs for detecting tactile and hydrodynamic stimuli. However, manatees are unique since these tactile hairs are located over the whole post-cranial body in addition to the face. These hairs have different densities at different locations of the body, with higher density on the dorsal side and density decreasing ventrally. The effect of this distribution in spatial resolution is unknown.
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Soricidae, a sister family of Talpidae, contains the American water shrew. This animal can obtain prey during the night despite the darkness. To discover how this is possible, a study controlling for use of electroreception, sonar, or echolocation showed that this water shrew is capable of detecting water disturbances made by potential prey. This species probably uses its vibrissae for hydrodynamic (and tactile) sensing based on behavioral observations and their large cortical representation.
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The sides of the maned sloth's face and neck feature long hair covering the short hair of the sloth's snout. Facial vibrissae on the maned sloth are sparse. The maned sloth earns its name from a mane of black hair running down its neck and over its shoulders. The mane is usually larger and darker in males than in females, and in the latter, may be reduced to a pair of long tufts.
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In many non-human mammals, the upper lip and sinus area is associated with whiskers or vibrissae which serve a sensory function. In humans, these whiskers do not exist but there are still sporadic cases where elements of the associated vibrissal capsular muscles or sinus hair muscles can be found. Based on histological studies of the upper lips of 20 cadavers, Tamatsu et al. found that structures resembling such muscles were present in 35% (7/20) of their specimens.
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The young are born bright pink, wrinkled, hairless (except for colorless vibrissae), poikilothermic, and with their eyes closed. Within 22 hours of birth, hair is already developing and beginning to obtain adult pigmentation, beginning at the head and eventually reaching the feet by day 7. Before day 9 it is not possible to differentiate sexes because external genitalia appear the same. Weaning is completed around day 25, and young begin hunting and scavenging independently by 4 weeks.
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Otariids have visible external ears, while phocids and walruses lack these. Pinnipeds have well-developed senses—their eyesight and hearing are adapted for both air and water, and they have an advanced tactile system in their whiskers or vibrissae. Some species are well adapted for diving to great depths. They have a layer of fat, or blubber, under the skin to keep warm in the cold water, and, other than the walrus, all species are covered in fur.
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Monodelphis kunsi is a relatively small opossum with short, warm-brown hair on its dorsal side. The ventral side of this pygmy opossum is a lighter color with pale, ivory patches of fur mixed throughout. In addition to fur, vibrissae can be found in three locations on the face, including the nose, above the eyes and near the ears, and under the chin. M. kunsi lacks a mid- sagittal crest; however, it does have a throat gland present.
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The large ears, eyes, and many vibrissae of the cat adapt it for lowlight predation Cat senses are adaptations that allow cats to be highly efficient predators. Cats are good at detecting movement in low light, have an acute sense of hearing and smell, and their sense of touch is enhanced by long whiskers that protrude from their heads and bodies. These senses evolved to allow cats to hunt effectively at night. (video) A cat blinking and looking around.
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One therocephalian, Nothogomphodon, had large saber-like canine teeth and may have fed on large animals, including other therocephalians. Other therocephalians such as bauriids and nanictidopids have wide teeth with many ridges similar to those of mammals, and may have been herbivores. Many small therocephalians have small pits on their snouts that probably supported vibrissae or whiskers. In 1994, the Russian paleontologist Leonid Tatarinov proposed that these pits were part of an electroreception system in aquatic therocephalians.
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Elephant seals do not have a developed a system of echolocation in the manner of cetaceans, but their vibrissae, which are sensitive to vibrations, are assumed to play a role in search of food. Males and females differ in diving behavior. Males tend to hug the continental shelf while making deep dives and forage along the bottom, while females have more jagged routes and forage in the open ocean. Elephant seals are prey for orcas and great white sharks.
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Vibrissae are more rigid and embedded much more deeply in the skin than other hairs and have a greater number of receptor cells at their base. They can detect air currents, subtle vibrations, and objects in the dark. They provide an early warning system for objects that might strike the face or eyes, and probably help direct food and objects towards the mouth., Santos, A "Puppy and Dog Care: An Essential Puppy Training Guide", 2015 Amazon Digital Services, Inc.
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The ears are external and both the eyes and ears are very small with long vibrissae on its head. The skull is specific in many ways; first, the infraorbital foramen is greatly enlarged so portions of the masseter extend through it and attach from the frontal side surface of the snout. Second, the angular process is inflected on the lower jaw, and third, the nasal cavity is enlarged. Prominent pockets create enlarged areas of attachment for chewing muscles.
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The diet of this species is not completely known. It is believed to feed on small aquatic arthropods and larvae. A close relative from genus Chibchanomys, also an aquatic ichthyomyine, was found to feed on small fish, arthropods, as well as terrestrial and aquatic insects. This genus hunts along the edge of streams using their vibrissae and once prey is caught the rodent takes it to a safe place (sometimes a burrow) on land to eat.
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The Brazilian arboreal mouse is a small mouse with small rounded ears and vibrissae (whiskers) long enough to reach the ears. The dorsal fur is reddish-brown which gradually fades to reddish-grey on the ventral surface. The hair is soft, and this distinguishes Rhagomys rufescens from the only other species in the genus, Rhagomys longilingua, which has spines mixed in with the hairs. They also differ in certain skull characteristics, and their ranges do not overlap.
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Hadrocodium, whose fossils date from approximately 195 million years ago, in the early Jurassic, provides the first clear evidence of a jaw joint formed solely by the squamosal and dentary bones; there is no space in the jaw for the articular, a bone involved in the jaws of all early synapsids. Fossil of Thrinaxodon at the National Museum of Natural History The earliest clear evidence of hair or fur is in fossils of Castorocauda and Megaconus, from 164 million years ago in the mid-Jurassic. In the 1950s, it was suggested that the foramina (passages) in the maxillae and premaxillae (bones in the front of the upper jaw) of cynodonts were channels which supplied blood vessels and nerves to vibrissae (whiskers) and so were evidence of hair or fur; it was soon pointed out, however, that foramina do not necessarily show that an animal had vibrissae, as the modern lizard Tupinambis has foramina that are almost identical to those found in the nonmammalian cynodont Thrinaxodon. Popular sources, nevertheless, continue to attribute whiskers to Thrinaxodon.
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The diet of Aonyx capensis primarily includes water-dwelling animals, such as crabs, fish, frogs and worms. They dive after prey to catch it, then swim to shore again, where they eat. Their fore paws come in handy as searching devices and are great tools for digging on the muddy bottoms of ponds and rivers, picking up rocks and looking under logs. Extremely sensitive whiskers (vibrissae) are used as sensors in the water to pick up the movements of potential prey.
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This population also has a red tail, which darkens at the end. Vibrissae are found above the eyes (superciliary), above the mouth (buccal), under the lower jaw (genal), near the top of the jaw (interramal), and on the wrist (carpal). Like mouse lemurs, the ears are large and membranous. Ear size is one differentiating factor between the northern giant mouse lemur and Coquerel's giant mouse lemur, with the former having shorter, rounded ears, while the latter has relatively large ears.
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They are able to identify objects before touching them with vibrissae located above their sharp, nonretractable claws. The raccoon's paws lack an opposable thumb; thus, it does not have the agility of the hands of primates. There is no observed negative effect on tactile perception when a raccoon stands in water below 10 °C (50 °F) for hours. Raccoons are thought to be color blind or at least poorly able to distinguish color, though their eyes are well-adapted for sensing green light.
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The vibrissae are connected to blood vessels, nerves, and muscles making them an important sensing tool. Due to evolutionary changes, their ear has been modified to work extremely well underwater. The structure of the inner ear helps amplify incoming sounds, and allows these seals to have good directional hearing due to the isolation of the inner ear. In addition to these adaptations, tissues in the ear canal allow the pressure in the ear to be adjusted while these seals perform their deep dives.
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Detection of hydrodynamic stimuli in mammals typically occurs through use of hairs (vibrissae) or “push-rod” mechanoreceptors, as in platypuses. When hairs are used, they are often in the form of whiskers and contain a follicle-sinus complex (F-SC), making them different from the hairs with which humans are most familiar.Dehnhardt, G, H Hyvärinen, A Palviainen, and G Klauer. “Structure and innervation of the vibrissal follicle-sinus complex in the Australian water rat, Hydromys chrysogaster.” The Journal of Comparative Neurology 411, no.
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Manatees, remarkably, have around 600 vibrissae on or around their lips. Whiskers can be very long in some species; the length of a chinchilla's whiskers can be more than a third of its body length (see image). Even in species with shorter whiskers, they can be very prominent appendages (see images). Thus, whilst whiskers certainly could be described as "proximal sensors" in contrast to, say, eyes, they offer a tactile sense with a sensing range that is functionally very significant.
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The Hawaiian monk seal has a relatively small, flat head with large black eyes, eight pairs of teeth, and short snouts with the nostril on top of the snout and vibrissae on each side. The nostrils are small vertical slits which close when the seal dives underwater. Additionally, their slender, torpedo-shaped body and hind flippers allow them to be very agile swimmers. Adult males are in weight and in length while adult females tend to be, on average, slightly larger, at and in length.
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Vibrissae are also found slightly above the wrist on the underside of the forearm. The ears are relatively large compared to other lemurs and are covered in hair, which has only small tufts if any. Although slight pattern variations in the facial region may be seen between individuals, there are no obvious differences between the sexes. Unlike most diurnal primates, but like all strepsirhine primates, the ring- tailed lemur has a tapetum lucidum, or reflective layer behind the retina of the eye, that enhances night vision.
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Both species are characterized by very long vibrissae (whiskers), but those of T. bolivaris are particularly long. In addition to whisker length and fur color, several other morphological differences distinguish the two, including the wider first upper molar in T. bolivaris. Species of Hylaeamys and Euryoryzomys also differ from Transandinomys in some details of the skull and teeth and have shorter whiskers. Species of Transandinomys live on the ground, are active during the night, eat both plant and animal matter, and construct nests of vegetation.
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These seizures were recorded on both sides of the brain, lasted about 20 sec and occurred when the animals were quiet. Importantly, SWD were always associated with a typical "arrest" of the rats' behavior with twitching of the vibrissae. In addition, drugs used in the clinic to stop absence seizures (ethosuccimide, valproate) suppressed SWDs in these rats, whereas those that aggravate these seizures in patients (carbamazepine, phenytoine), increased rats' seizures.Micheletti, G., Vergnes, M., Marescaux, C., Reis, J., Depaulis, A., Rumbach, L., Warter, J.M., 1985.
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The upper, smooth whisker belongs to a California sea lion. The lower undulated whisker belongs to a harbor seal. Harbor seals have been observed following varying paths of other organisms that swam ahead several minutes before, similar to a dog following a scent trail, and even to discriminate the species and the size of the fish responsible for the trail. Blind ringed seals have even been observed successfully hunting on their own in Lake Saimaa, likely relying on their vibrissae to gain sensory information and catch prey.
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In a Ficus racemosa, in Polo Forest, Sabarkantha, Gujarat, India This is a large species, with a head and body length of about 43 cm and a tail of 50–52 cm. It has black to gray-brown fur, long and soft on the upper parts and somewhat shorter underneath the body, with a grizzled appearance. A wing membrane between the forelimb and hindlimb, paler coloured underneath, allows gliding between trees. The tail is hairy and blackish to gray-brown, the feet are black, and the nose is pale pink with black vibrissae.
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Pups on St. Paul Island, Alaska Along with the previously mentioned thick underfur, fur seals are distinguished from sea lions by their smaller body structure, greater sexual dimorphism, smaller prey, and longer foraging trips during the feeding cycle. The physical appearance of fur seals varies with individual species, but the main characteristics remain constant. Fur seals are characterized by their external pinnae, dense underfur, vibrissae, and long, muscular limbs. They share with other otariids the ability to rotate their rear limbs forward, supporting their bodies and allowing them to ambulate on land.
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An hCONDEL located near the locus of the androgen receptor (AR) gene may be responsible for the loss of whiskers and penile spines in humans compared to its close relatives, including chimpanzees. The 60.7kb hCONDEL which is located near the AR locus has been found to be responsible for removing a 5 kb sequence that codes for an enhancer for the AR locus. Using the mouse construct with LacZ expression showed localization of this hCONDEL region (AR enhancer) to the mesenchyme of vibrissae follicles and the mesoderm cells of penile organs.
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The southern marsupial mole is small in size, with a head and body length varying from 121 to 159 mm, a tail length of 21–26 mm and a weight of 40-70 g. The body is covered with short, dense, silky fur with a pale cream to white color often tinted by the iron oxides from the soil which gives it a reddish chestnut brown tint. It has a light brownish pink nose and mouth and no vibrissae. The cone shaped head merges directly with the body, and there is no obvious neck region.
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Their mystacial vibrissae have ten times the innervation of terrestrial mammals, allowing them to effectively detect vibrations in the water. These vibrations are generated, for example, when a fish swims through water. Detecting vibrations is useful when the animals are foraging and may add to or even replace vision, particularly in darkness. Harbor seals have been observed following varying paths of another seal that swam ahead several minutes before, similar to a dog following a scent trail, and even to discriminate the species and the size of the fish responsible for the trail.
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A fur seal grooming itself at the Cape Cross Seal Reserve on the Skeleton Coast Skull of male brown fur seal The brown fur seal is the largest and most robust member of the fur seals. It has a large and broad head with a pointed snout that may be flat or turned up slightly. They have external ear flaps (pinnae) and their whiskers (vibrissae) are long, and may extend backward past the pinnae, especially in adult males. The fore flippers are covered with sparse hair over about three-quarters of their length.
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Mediterranean monk seal skeleton The Hawaiian monk seal (whose Hawaiian name means "the dog that runs in rough waters") has a short, broad, and flat snout, with long nostrils that face forward. It has a relatively small, flat head with large, black eyes, eight pairs of teeth, and a short snout with the nostrils on top of the snout and vibrissae on each side. The nostrils are small, vertical slits, which close when the seal dives under water. Additionally, their slender, torpedo-shaped body and hind flippers allow them to be very agile swimmers.
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Their muzzles are distinguished as broad and convex, and tapering out toward the end. The top of the snout is covered in short and fine fur, interspersed with short whiskery vibrissae, although not the longer bristles found in the related species Setirostris eleryi (Mormopterus eleryi). With an exception in several of the species, and especially Ozimops halli, the dental formula is 1/2, 1/1, 2/2, 3/3 = 30. The variation to this is the loss of a tooth in mature individuals, the upper anterior premolar, at one or both sides of the jaw.
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There is some experimental evidence to suggest that they may prevent particles from striking the eyes if, for example, a prey item is missed or broken apart on contact. They may also help to protect the eyes from particles encountered in flight, or from casual contact from vegetation. There is also evidence that the rictal bristles of some species may function tactilely, in a manner similar to that of mammalian whiskers (vibrissae). Studies have shown that Herbst corpuscles, mechanoreceptors sensitive to pressure and vibration, are found in association with rictal bristles.
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Skull with dentition: 2/2 molars, 4/4 premolars, 1/1 canines, 3/3 incisors Skeleton Baculum or penis bone Lower side of front paw with visible vibrissae on the tips of the digits Head to hindquarters, raccoons measure between , not including the bushy tail which can measure between , but is usually not much longer than . The shoulder height is between . The body weight of an adult raccoon varies considerably with habitat, making the raccoon one of the most variably sized mammals. It can range from , but is usually between .
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However, it prefers benthic bivalve mollusks, especially clams, for which it forages by grazing along the sea bottom, searching and identifying prey with its sensitive vibrissae and clearing the murky bottoms with jets of water and active flipper movements. The walrus sucks the meat out by sealing its powerful lips to the organism and withdrawing its piston-like tongue rapidly into its mouth, creating a vacuum. The walrus palate is uniquely vaulted, enabling effective suction. The diet of the Pacific walrus consist almost exclusively of benthic invertebrates (97 percent).
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Studies raise the question of how detection of hydrodynamic stimuli in these animals is possible given the movement of the vibrissae due to water flow during swimming. Whiskers vibrate with a certain frequency based on swim speed and properties of the whisker. Detection of the water disturbance caused by this vibrissal movement should overshadow any stimulus produced by a distant fish due to its proximity. For seals, one proposal is that they might sense changes in the baseline frequency of vibration to detect hydrodynamic stimuli produced by another source.
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The average dive depth ranges from 10 to 15 m, however, their maximum dive depths were limited by environmental depth. The saimaa ringed seal has also been observed to have seasonal hauling- out patterns. In May and June, when the seals are molting, they are observed to haul out both day and night, however, in late summer they are observed to haul out only at night. The saimaa ringed seal is able to complete its dives and navigate in its environment due to its highly developed vibrissae, also known as whiskers.
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Because the flanks lack entirely dark cover hairs, they are slightly lighter than the rest of the upperparts. They are sharply separated in color from the underparts, which are entirely white to buffish. The mystacial vibrissae (whiskers above the mouth) are long, up to 60 mm (2.4 in), and white or black in color. The pinnae (external ears) are dark brown and covered with fine gray hairs,Goodman and Soarimalala, 2005, p. 455 and ear length is 32 mm (1.3 in). Hindfoot length is 37 mm (1.5 in).
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The walrus, an aquatic molluscivore Whales: Sperm whales, pilot whales, Cuvier's beaked whale, Risso's dolphin and species in the genera Mesoplodon, and Hyperoodon and the superfamily Physeteroidea are classified as molluscivores, eating mainly squid. Pinnipeds: Elephant seals, Ross seals and South American fur seals are classed as molluscivores. The walrus eats benthic bivalve molluscs, especially clams, for which it forages by grazing along the sea bottom, searching and identifying prey with its sensitive vibrissae. The walrus sucks the meat out by sealing its powerful lips to the organism and withdrawing its piston-like tongue rapidly into its mouth, creating a vacuum.
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Because the feathers do not need the strength and stiffness required for flight, they are exceptionally soft, giving rise to the specific epithet habroptilus. The kakapo has a conspicuous facial disc of fine feathers resembling the face of an owl; thus, early European settlers called it the "owl parrot". The beak is surrounded by delicate feathers which resemble vibrissae or "whiskers"; it is possible kakapo use these to sense the ground as they walk with its head lowered, but there is no evidence for this. The mandible is variable in colour, mostly ivory, with the upper part often bluish-grey.
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As in other sensory cortices, S1 neurons are grouped together with similar inputs and responses into vertical columns that extend across cortical layers (e.g., As shown by Vernon Mountcastle, into alternating layers of slowly adapting and rapidly adapting neurons; or spatial segmentation of the vibrissae on mouse/rat cerebral cortex). This area of cortex, as shown by Wilder Penfield and others, is organized somatotopically, having the pattern of a homunculus. That is, the legs and trunk fold over the midline; the arms and hands are along the middle of the area shown here; and the face is near the bottom of the figure.
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The noses of five prosimian primates: (A) dwarf lemur, (B) greater galago, (C) lesser galago, (D) aye-aye, and (E) a tarsier (A) through (D) possess a rhinarium and are strepsirrhines, whereas (E) does not and is a haplorhine. Strepsirrhines have a long snout that ends in a moist and touch-sensitive rhinarium, similar to that of dogs and many other mammals. The rhinarium is surrounded by vibrissae that are also sensitive to touch. Convoluted maxilloturbinals on the inside of their nose filter, warm, and moisten the incoming air, while olfactory receptors of the main olfactory system lining the ethmoturbinals detect airborne smells.
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The tail is more muscular, especially at the base, and in colour generally like the body, but commonly paler at the base beneath. The body hairs are frequently partly whitish or buff, giving a speckled appearance to the pelage, sometimes so pale that the whole body is mostly straw-coloured or grey, the young being often at all events paler than the adults, but the head is always closely speckled with grey or buff. The long mystacial vibrissae are conspicuously white, and there is a white rim on the summit of the otherwise black ear. The glandular area is whitish.
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There is a cinnamon colored dorsal stripe running from the crown of the head or the shoulders to the end of the tail. The head of this species has a pale neutral gray spot above the nose, cinnamon around the eyes, a clay colored crown, and eras that are light neutral gray. The dorsal side of the tail is cinnamon colored while the ventral side is grayish-beige on the most distal two-thirds and cinnamon with faint brownish black streaks on the proximal one-third. The hands and feet are colored grayish-white and the vibrissae are dark in color.
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The silver mountain vole (Alticola argentatus) is a species of rodent in the family Cricetidae. They are distinguished by their silver-grey pelage, long vibrissae, rootless hypsodont molars and angular skull shape. Like many mammals of the Eurasian Steppe eco-region, they are well adapted to life in high altitudes, and can be found in mountain areas of Central and North Asia from the Chukchi Peninsula in the north-east to Kugitang Range in the west, and to Tibet and the Himalayas in the south.Adam Nadachowski and Jim I. Mead, "Alticola argentatus", Oxford University Press, December 1999.
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In the case of the barrel field, the map is somatotopic - based on the arrangement of body parts. Areas corresponding to the nose and mouth are more rostral and lateral in the map, the forelimb, hindlimb and trunk are more medial, with the forelimb rostral of the hindlimb, and the whisker barrel subfields - the posteromedial barrel subfield, which corresponds to the major facial whiskers (the mystacial vibrissae), and the anteriolateral barrel subfield, which corresponds to the smaller whiskers of the face - are caudal and lateral. Although the whiskers make up a relatively small portion of the animal, they dominate the somatotopic map.Hoover et al.
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However, during the Antarctic winter darkness, when there is no light under the ice where the seals forage, they rely on other senses, primarily the sense of touch from their vibrissae or whiskers, which are not just hairs, but very complicated sense organs with more than 500 nerve endings that attach to the animal's snout. The hairs allow the seals to detect the wake of swimming fish and use that to capture prey. Weddell seals have no natural predators when on fast ice. At sea or on pack ice, they are prey for killer whales and leopard seals, which prey primarily on juveniles and pups.
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H. semispinosus possesses sensory hairs that are scattered on the dorsum that are similar to vibrissae. The streaked tenrec has an evolutionary adaptation for its semifossorial habits with a well developed lateral and long heads of M. triceps brachii and enlarged M. teres major that function as an extensor of the elbow joint and as an adductor of the upper arm for digging. This species also has elongated hands and second, third, and fourth digit adaptation that acts as the main fossorial adaptation. The middle of the skull of this species is long and low, the alveolar processes of the maxilla, premaxilla and mandible are reduced and the palate narrow.
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The species was first described in 1891 by Joel Asaph Allen and thereafter a variety of names, now considered synonyms, were applied to local populations. It was lumped into a widespread species "Oryzomys capito" (now Hylaeamys megacephalus) from the 1960s until the 1980s and the current allocation of synonyms dates from 1998. It was placed in the genus Oryzomys until 2006, as Oryzomys talamancae, but is not closely related to the type species of that genus and was therefore moved to a separate genus Transandinomys in 2006. It shares this genus with Transandinomys bolivaris, which has even longer vibrissae; the two overlap broadly in distribution and are morphologically similar.
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The family was recently treated by Lonsdale (2013), who redefined the family and its genera, synonymizing all other neotropical tanypezid genera in Neotanypeza. Lonsdale (2014) also provided a full catalogue for the family. Species of Tanypezidae are relatively large, and have semispherical heads and stout bodies that are perched atop long, thin legs, the latter of which have sometimes allied them with the families Neriidae and Micropezidae. The head and thorax are also often very dark with contrasting silver- (sometimes golden-) haired stripes and spots. Furthermore, apical convergence of wing veins R4+5 and M1 occurs, and no vibrissae, setulae on the upper surface of vein R1, and a large, flat “ocellar disc behind the ocelli.
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However, vibrissae are different from other hair structures because they grow from a special hair follicle incorporating a capsule of blood called a blood sinus which is heavily innervated by sensory nerves. The mystacial macrovibrissae are shared by a large group of land and marine mammals (see images), and it is this group that has received by far the most scientific study. The arrangement of these whiskers is not random: they form an ordered grid of arcs (columns) and rows, with shorter whiskers at the front and longer whiskers at the rear (see images). In the mouse, gerbil, hamster, rat, guinea pig, rabbit, and cat, each individual follicle is innervated by 100–200 primary afferent nerve cells.
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Because the barrel cortex has a well-organised structure that relates clearly to the whisker pad, it has been used extensively as a tool to study sensory processing and development, and the phenomenon of experience-dependent plasticity - changes in the activity, connectivity, and structure of neural circuits in response to experience. Neurons in the barrel cortex exhibit the property of synaptic plasticity that allows them to alter the vibrissae to which they respond depending on the rodent's history of tactile experience.Hardingham N, Glazewski S, Pakhotin P, Mizuno K, Chapman PF, Giese KP, Fox K. Neocortical long-term potentiation and experience-dependent synaptic plasticity require alpha-calcium/calmodulin-dependent protein kinase II auto-phosphorylation. J Neurosci. 2003 Jun 1;23(11):4428-36.
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Viverrids are the most primitive of all the families of feliform Carnivora and clearly less specialized than the Felidae. In external characteristics, they are distinguished from the Felidae by the longer muzzle and tuft of facial vibrissae between the lower jaw bones, and by the shorter limbs and the five- toed hind foot with the first digit present. The skull differs by the position of the postpalatine foramina on the maxilla, almost always well in advance of the maxillopalatine suture, and usually about the level of the second premolar; and by the distinct external division of the auditory bulla into its two elements either by a definite groove or, when rarely this is obliterated, by the depression of the tympanic bone in front of the swollen entotympanic. The typical dental formula is: , but the number may be reduced, although never to the same extent as in the Felidae.
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The fur of mammals has many uses: protection, sensory purposes, waterproofing, and camouflaging, with the primary usage being thermoregulation. The types of hair include definitive, which may be shed after reaching a certain length; vibrissae, which are sensory hairs and are most commonly whiskers; pelage, which consists of guard hairs, under-fur, and awn hair; spines, which are a type of stiff guard hair used for defense in, for example, porcupines; bristles, which are long hairs usually used in visual signals, such as the mane of a lion; velli, often called "down fur," which insulates newborn mammals; and wool, which is long, soft, and often curly. Hair length is negligible in thermoregulation, as some tropical mammals, such as sloths, have the same fur length as some arctic mammals but with less insulation; and, conversely, other tropical mammals with short hair have the same insulating value as arctic mammals. The denseness of fur can increase an animal's insulation value, and arctic mammals especially have dense fur; for example, the musk ox has guard hairs measuring as well as a dense underfur, which forms an airtight coat, allowing them to survive in temperatures of .
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