Strepsirrhini or Strepsirhini is a suborder of primates that includes the lemuriform primates, which consist of the lemurs of Madagascar, galagos ("bushbabies") and pottos from Africa, and the lorises from India and southeast Asia. Collectively they are referred to as strepsirrhines. Also belonging to the suborder are the extinct adapiform primates which thrived during the Eocene in Europe, North America, and Asia, but disappeared from most of the Northern Hemisphere as the climate cooled. Adapiforms are sometimes referred to as being "lemur-like", although the diversity of both lemurs and adapiforms does not support this comparison.
Haplorhini, the haplorhines or the "dry-nosed" primates, is a suborder of primates containing the tarsiers and the simians, as sister of the Strepsirrhini ("moist-nosed"). The name is sometimes spelled Haplorrhini. The simians include catarrhines, and the platyrrhines.
The simians, anthropoids, or higher primates are an infraorder of primates containing all animals traditionally called monkeys and apes. More precisely, they consist of the parvorders New World monkeys (Platyrrhini) and Catarrhini, the latter of which consists of the family Cercopithecidae and the superfamily Hominoidea.
Eosimiidae is the possible family of extinct primates believed to be the earliest simians.
Catopithecus is an early catarrhine fossil. It is known from more than 16 specimens of a single species, Catopithecus browni, found in the Jebel Qatrani Formation of the Fayum Province, Egypt. The Jebel Qatrani Formation has been divided into two main faunal zones based on the fact that the fauna found in the lower portion of the quarry appear to be more primitive than those found in the upper section. The upper zone has been dated to older than 31 ± 1 myr based on the dating of a basalt layer that lies immediately above the formation and Nicolas Steno’s Law of Superposition. The lower zone contains the late Eocene green shale unit called Locality-41 (L-41) in which all the specimens of Catopithecus browni have been found. The relative dating of L-41 based on paleomagnetic correlations places it at 36 Myr according to Simons et al (1999), but Seiffert (2006) suggests this should be revised to 34.8-33.9 Myr.
Darwinius is a genus within the infraorder Adapiformes, a group of basal strepsirrhine primates from the middle Eocene epoch. Its only known species, Darwinius masillae, lived approximately 47 million years ago based on dating of the fossil site.
Ganlea is a fossil primate from central Myanmar, formerly known as Burma. Its age is about 38 million years, living during the late Eocene epoch. Ganlea belongs to the group of anthropoids, and is in the family Amphipithecidae. It is older than any other known anthropoid from Africa, and is the second oldest known from Asia. Its remains consist of teeth and jawbones belonging to 10 to 15 individuals found near the city of Bagan in the central part of the country.
Algeripithecus is an extinct genus of early fossil primate, weighing approximately 65 to 85 grams. Fossils have been found in Algeria dating from 50 to 46 million years ago.
K. Christopher Beard is an American paleontologist, an expert on the primate fossil record and a 2000 MacArthur Fellowship "Genius" Award Winner. Beard's research is reshaping critical debates about the evolutionary origins of mammals, including primates, routinely questioning current thinking about their geographical origins. Dr. Beard is the former Curator of the Carnegie Museum of Natural History, and Mary R. Dawson Chair of Vertebrate Paleontology, at University of Pittsburgh. He is currently Distinguished Foundation Professor, Senior Curator at the University of Kansas. He was co-author with Dan Gebo about an extinct primate from China. Dr. Beard also authored the book The Hunt for the Dawn Monkey: Unearthing the Origins of Monkeys, Apes and Humans. Beard was also part of the research teams that discovered Teilhardina, the earliest primate ever found in North America, and Eosimias, one of the earliest higher primates yet discovered. He worked with NASA to scan a Tyrannosaurus rex skull. Beard received his PhD from the Functional Anatomy and Evolution Program at Johns Hopkins University School of Medicine in 1989.
Parapithecidae is an extinct family of primates which lived in the Eocene and Oligocene periods in Egypt. Eocene fossils from Myanmar are sometimes included in the family in addition. They showed certain similarities in dentition to Condylarthra, but had short faces and jaws shaped like those of tarsiers. They are part of the superfamily Parapithecoidea, perhaps equally related to Ceboidea and Cercopithecoidea plus Hominoidea - but the placement of Parapithecoidea is substantially uncertain.
Azibiidae is an extinct family of fossil primate from the late early or early middle Eocene from the Glib Zegdou Formation in the Gour Lazib area of Algeria. They are thought to be related to the living toothcombed primates, the lemurs and lorisoids, although paleoanthropologists such as Marc Godinot have argued that they may be early simians. It includes the genera Azibius and Algeripithecus, the latter of which was originally considered the oldest known simian, not a strepsirrhine.
Azibius is an extinct genus of fossil primate from the late early or early middle Eocene from the Glib Zegdou Formation in the Gour Lazib area of Algeria. They are thought to be related to the living toothcombed primates, the lemurs and lorisoids, although paleoanthropologists such as Marc Godinot have argued that they may be early simians. Originally described as a type of plesiadapiform, its fragmentary remains have been interpreted as a hyopsodontid, an adapid, and a macroscelidid. Less fragmentary remains discovered between 2003 and 2009 demonstrated a close relationship between Azibius and Algeripithecus, a fossil primate once thought to be the oldest known simian. Descriptions of the talus in 2011 have helped to strengthen support for the strepsirrhine status of Azibius and Algeripithecus, which would indicate that the evolutionary history of lemurs and their kin is rooted in Africa.
Djebelemur is an extinct genus of early strepsirrhine primate from the late early or early middle Eocene period from the Chambi locality in Tunisia. Although they probably lacked a toothcomb, a specialized dental structure found in living lemuriforms, they are thought to be a related stem group. The one recognized species, Djebelemur martinezi, was very small, approximately 100 g (3.5 oz).
Afrasia djijidae is a fossil primate that lived in Myanmar approximately 37 million years ago, during the late middle Eocene. The only species in the genus Afrasia, it was a small primate, estimated to weigh around 100 grams (3.5 oz). Despite the significant geographic distance between them, Afrasia is thought to be closely related to Afrotarsius, an enigmatic fossil found in Libya and Egypt that dates to 38–39 million years ago. If this relationship is correct, it suggests that early simians dispersed from Asia to Africa during the middle Eocene and would add further support to the hypothesis that the first simians evolved in Asia, not Africa. Neither Afrasia nor Afrotarsius, which together form the family Afrotarsiidae, is considered ancestral to living simians, but they are part of a side branch or stem group known as eosimiiforms. Because they did not give rise to the stem simians that are known from the same deposits in Africa, early Asian simians are thought to have dispersed from Asia to Africa more than once prior to the late middle Eocene. Such dispersals from Asia to Africa also were seen around the same time in other mammalian groups, including hystricognathous rodents and anthracotheres.
Afrotarsius is a primate found in the Paleogene of Africa.
The evolutionary history of the primates can be traced back 57-90 million years. One of the oldest known primate-like mammal species, Plesiadapis, came from North America; another, Archicebus, came from China. Other similar basal primates were widespread in Eurasia and Africa during the tropical conditions of the Paleocene and Eocene. Purgatorius is the genus of the four extinct species believed to be the earliest example of a primate or a proto-primate, a primatomorph precursor to the Plesiadapiformes, dating to as old as 66 million years ago.
Amphipithecus mogaungensis was a primate that lived in Late Eocene Myanmar. Along with another primate Pondaungia cotteri, both are difficult to categorise within the order Primates. What little is known suggests that they are neither adapiform nor omomyid primates, two of the earliest primate groups to appear in the fossil record. Deep mandibles and mandibular molars with low, broad crowns suggest they are both simians, a group that includes monkeys, apes, and humans, though more material is needed for further comparison. The teeth also suggest that these were frugivore primates, with a body mass of 6–10 kg (13–22 lb).
Afradapis is a genus of adapiform primate that lived during the Late Eocene. The only known species, Afradapis longicristatus, was discovered in the Birket Qarun Formation in northern Egypt in 2009. While its geographic distribution is confined to Afro-Arabia, Afradapis belongs to the predominantly European adapiform family Caenopithecidae. This taxonomic placement is supported by recent phylogenetic analyses that recover a close evolutionary relationship between Afradapis and adapiforms, including Darwinius. While adapiforms have been noted for their strepsirrhine-like morphology, no adapiform fossil possesses the unique anatomical traits to establish an ancestor-descent relationship between caenopithecids and living strepsirrhines. It ate leaves and moved around slowly like lorises.
The Amphipithecidae were simian primates that lived in Late Eocene and Early Oligocene. Fossils have been found in Myanmar, Thailand, and Pakistan. The limited fossil evidence is consistent with, but not exclusive to, arboreal quadrupedalism. In other words, the species may have moved about in trees on four legs, but not with regular leaping as seen in later simians.
Phileosimias is an extinct genus of primates with two species, P. kamli and P. bahuiorum, that are believed to be amongst the early simians.
