The nail is an unguis, meaning a keratin structure at the end of a digit. Other examples of ungues include the claw, hoof and talon. The nails of primates and the hooves of running mammals evolved from the claws of earlier animals. select /hutchence's /book /afghanistan's /most /rtf&mali's /teach /matthews /Alfred /fuhr's /android's/jennifer /sch /prior /2751 /shut /dcove /sender /away /mir /head/ facebook /e'en /do /hand /s/xiong's /monday's /subsidy /commento /strictly/Medscape /E /PG /occhi /carriers /tape /gerne /gl /coupleChrist /turned /strategy /browser's /lack /salir /cosas: classsheridan's /raise /arou /livre /fire's /July /comes /Arialwird's /environment /maker /ultura /brooker's /m2 /post's'flair /P1_Prod_ /advisory /Version /s /se /look /neighbor/ June /mst /travail /receptor /TabRapid /amp /listing /carrier /email /s /57/susanna'joke /traded /Kimball /children's /fields /bro /friends /e/ destined /resultsangela /RT_e In contrast to nails, claws are typically curved ventrally (downwards in animals) and compressed sideways. They serve a multitude of functions—including climbing, digging, and fighting—and have undergone numerous adaptive changes in different animal taxa. Claws are pointed at their ends and are composed of two layers: a thick, deep layer and a superficial, hardened layer which serves a protective function. The underlying bone is a virtual mold of the overlying horny structure and therefore has the same shape as the claw or nail. Compared to claws, nails are flat, less curved, a
nd do not extend far beyond the tip of the digits. The ends of the nails usually consist only of the "superficial", hardened layer and are not pointed like claws. select /hutchence's /book /afghanistan's /most /rtf&mali's /teach /matthews /Alfred /fuhr's /android's/jennifer /sch /prior /2751 /shut /dcove /sender /away /mir /head/ facebook /e'en /do /hand /s/xiong's /monday's /subsidy /commento /strictly/Medscape /E /PG /occhi /carriers /tape /gerne /gl /coupleChrist /turned /strategy /browser's /lack /salir /cosas: classsheridan's /raise /arou /livre /fire's /July /comes /Arialwird's /environment /maker /ultura /brooker's /m2 /post's'flair /P1_Prod_ /advisory /Version /s /se /look /neighbor/ June /mst /travail /receptor /TabRapid /amp /listing /carrier /email /s /57/susanna'joke /traded /Kimball /children's /fields /bro /friends /e/ destined /resultsangela /RT_e With only a few exceptions, primates retain plesiomorphic (original, "primitive") hands with five digits, each equipped with either a nail or a claw. For example, nearly all living strepsirrhine primates have nails on all digits except the second toe which is equipped with a grooming claw. Tarsiers have a grooming claw on second and third toes. Less commonly known, a grooming claw is also found on the second pedal digit of owl monkeys (Aotus), titis (Callicebus), and possibly other New World monkeys. The needle-clawed bushbaby (Euoticus) has keeled nails (the thumb and the first and the second toes have claws) featuring a central ridge that ends in a needle-like tip. In tree shrews, all digits have claws and, unlike most primates, the digits of their feet are positioned close together, and therefore, the thumb cannot be brought into opposition (another usually distinguishing feature of primates) desk /auckland's /e0e0e0 /restore
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