Adapid

Adapid

Taxobox
name = Adapids
fossil_range = Early - Late Eocene
regnum = Animalia
phylum = Chordata
classis = Mammalia
ordo = Primates
subordo = Strepsirrhini
familia = Adapidae
subdivision_ranks = Genera
subdivision = "Adapis"
"Adapoides"
"Cryptadapis"
"Leptadapis"
"Microadapis"
"Paleolemur"

Adapids (members of the taxon Adapidae) are a diverse group of extinct primates that primarily radiated during the Eocene epoch between about 55 and 34 million years ago. However, one specialized endemic Asian group (sivaladapines) survived into the Miocene. Fossils of adapids are known from North America, Europe, Asia, and Africa. Adapids are one of two groups of Eocene primates with a geographic distribution spanning holarctic continents, the other being the omomyids (Omomyidae). Early representatives of the Adapidae (e.g., "Cantius" and "Donrussellia") and Omomyidae (e.g, "Teilhardina" and "Melanerimia") are some of the earliest known crown primates.

Features that characterize many adapids include small orbits (eye sockets), elongate rostra, cheek teeth adapted for folivorous or frugivorous diets, and relatively large body mass (i.e., greater than 1 kg). However, the endemic radiation of adapids in the early and middle Eocene of Europe included a number of taxa (e.g., "Anchomomys") that were very small (about 250 g or less) and partly insectivorous. Small orbits in genera such as "Notharctus", "Smilodectes", "Adapis", "Leptadapis", and "Mahgarita" indicate that these taxa were probably diurnal. At least one adapid genus from the late Eocene of Europe ("Pronycticebus") had large orbits and was probably nocturnal.

Like living primates, adapids had grasping hands and feet with digits tipped by nails instead of claws. Other aspects of the postcranium suggest that most adapids were arboreal quadrupeds. North American endemic adapids (notharctines) like "Notharctus" had extremely long digits and postcranial proportions that superficially resemble those of living lemurid primates. By contrast, some authors have suggested that one group of late Eocene European adapids (adapines) demonstrate adaptations for suspension and slow climbing.

Adapid systematics and evolutionary relationships are controversial, but there is fairly good evidence from the postcranium that adapids are stem strepsirrhines (early members of the group including the living lemurs, lorises, and bushbabies). In particular, the anatomy of the adapid ankle (e.g., position of the groove for the flexor fibularis tendon on the talus, the presence of a sloping talo-fibular facet) and wrist show derived similarities with those of living strepsirrhines. However, adapids also lack many of the anatomical specializations characteristic of living strepsirrhines, such as a tooth comb, a grooming claw on the second pedal digit, and a reduction in the size of the promontory branch of the internal carotid artery.

References

ee also

*Omomyidae

External links

*http://www.geocities.com/CapeCanaveral/Lab/8932/Adapidae.html
* [http://www.fmnh.helsinki.fi/users/haaramo/Metazoa/Deuterostoma/Chordata/Synapsida/Eutheria/Primates/Strepsirrhini.htm Mikko's Phylogeny Archive]


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  • Adapid — n. 1. 1 extinct small mostly diurnal lower primates that fed on leaves and fruit; abundant in North America and Europe 30 to 50 million years ago; their descendents probably include the lemurs and lorises; some authorities consider them ancestral …   The Collaborative International Dictionary of English

  • Adapid — noun extinct small mostly diurnal lower primates that fed on leaves and fruit; abundant in North America and Europe 30 to 50 million years ago; their descendents probably include the lemurs; some authorities consider them ancestral to anthropoids …   Useful english dictionary

  • Adapid group — noun extinct small mostly diurnal lower primates that fed on leaves and fruit; abundant in North America and Europe 30 to 50 million years ago; their descendents probably include the lemurs; some authorities consider them ancestral to anthropoids …   Useful english dictionary

  • Primate — Primates Primates …   Wikipédia en Français

  • Primates — Primates …   Wikipédia en Français

  • order Primates — noun an animal order including lemurs and tarsiers and monkeys and apes and human beings • Syn: ↑Primates • Hypernyms: ↑animal order • Member Holonyms: ↑Eutheria, ↑subclass Eutheria • Member Meronyms …   Useful english dictionary

  • Primates — noun an animal order including lemurs and tarsiers and monkeys and apes and human beings (Freq. 1) • Syn: ↑order Primates • Hypernyms: ↑animal order • Member Holonyms: ↑Eutheria, ↑subclass Eutheria …   Useful english dictionary

  • taxonomic category — noun animal or plant group having natural relations • Syn: ↑taxonomic group, ↑taxon • Hypernyms: ↑biological group • Hyponyms: ↑Adapid, ↑Adapid group, ↑Om …   Useful english dictionary

  • taxonomic group — noun animal or plant group having natural relations • Syn: ↑taxonomic category, ↑taxon • Hypernyms: ↑biological group • Hyponyms: ↑Adapid, ↑Adapid group, ↑ …   Useful english dictionary

  • Strepsirrhini — Taxobox name = StrepsirrhinesMSW3 Groves|pages=111 127|id=12100002] fossil range = Early Eocene Recent image width = 209px image caption =Verreaux s Sifaka ( Propithecus verreauxi ) regnum = Animalia phylum = Chordata classis = Mammalia ordo =… …   Wikipedia

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