''Ganlea'' is a fossil

primate Primates are a diverse order of mammals. They are divided into the strepsirrhines, which include the lemurs, galagos, and lorisids, and the haplorhines, which include the tarsiers and the simians ( monkeys and apes, the latter including ...

from central

Myanmar Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John Wells explai ...

, formerly known as Burma. Its age is about 38 million years, living during the late

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

epoch. ''Ganlea'' belongs to the group of anthropoids (i. e. humans, apes and monkeys), and is in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Amphipithecidae 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 ...

. It is older than any other known anthropoid from

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

, and is the second oldest known from

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

. 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. The teeth of ''Ganlea'' have many diagnostic features that help to show its relations with other anthropoids. It is thought to be closely related to the genera '' Myanmarpithecus'', '' Pondaungia'' and '' Siamopithecus'', both found from the same area as ''Ganlea''. In all of these genera, the

canine tooth In mammalian oral anatomy, the canine teeth, also called cuspids, dog teeth, or (in the context of the upper jaw) fangs, eye teeth, vampire teeth, or vampire fangs, are the relatively long, pointed teeth. They can appear more flattened howeve ...

is enlarged and compressed anteroposteriorly, making it quite wide. A great deal of tooth wear has been observed in ''Ganlea'', which has been viewed as an adaptation for consuming nuts and seeds, similar to the modern

Saki monkey Sakis, or saki monkeys, are any of several New World monkeys of the genus ''Pithecia''. They are closely related to the bearded sakis of genus ''Chiropotes''. Range Sakis' range includes northern and central South America, extending from the so ...

. The large size of the canine tooth in ''Ganlea'' gives it the specific name "''megacanina''". Phylogenetic analyses conducted upon the description of ''Ganlea'' suggest that the amphipithecids are closely related to

New World monkey New World monkeys are the five families of primates that are found in the tropical regions of Mexico, Central and South America: Callitrichidae, Cebidae, Aotidae, Pitheciidae, and Atelidae. The five families are ranked together as the Ceboidea ...

s (Platyrrhini) and the extinct propliopithecids. This places it firmly within Haplorrhini. ''

Darwinius ''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 (Lutetian stage) based ...

'', a primate recently described and quickly claimed a

transitional fossil A transitional fossil is any fossilized remains of a life form that exhibits traits common to both an ancestral group and its derived descendant group. This is especially important where the descendant group is sharply differentiated by gross a ...

of great importance to human ancestry, is a member of the

Adapiformes Adapiformes is a group of early primates. Adapiforms radiated throughout much of the northern continental mass (now Europe, Asia and North America), reaching as far south as northern Africa and tropical Asia. They existed from the Eocene to the M ...

, which has recently been viewed as a transitional group between Strepsirrhini and Haplorrhini. This means that ''Ganlea'' is more closely related to modern monkeys and apes than ''Darwinius'' is. Because of its age, ''Ganlea'' has been called a missing link that places the origin of all anthropoids (including

human Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, cultu ...

s) in Asia rather than Africa as was previously thought. However, doubts have been raised towards the claim that it is the ancestor of all other anthropoids. Other extinct primates such as ''

Eosimias ''Eosimias'' is a genus of early primates, first discovered and identified in 1999 from fossils collected in the Shanghuang fissure-fillings of Liyang, the southern city of Jiangsu Province, China. It is a part of the family Eosimiidae, and in ...

'' seem to be more basal members than ''Ganlea''.The description of ''Eosimias'' by

Beard A beard is the hair that grows on the jaw, chin, upper lip, lower lip, cheeks, and neck of humans and some non-human animals. In humans, usually pubescent or adult males are able to grow beards. Throughout the course of history, societal at ...

''et al.'' in 1994 can be seen as the beginning of the recent debate on the Asian ancestry of anthropoids Because ''Ganlea'' is a true anthropoid, it has been seen as more likely to be a direct ancestor of monkeys and apes (and thus humans) than ''Darwinius'' would. However, the phylogenetic analysis that was conducted on it suggests that it is too derived to have been an ancestral anthropoid, and its close relation with New World monkeys seems to imply that it was not a human ancestor, as apes are believed to have evolved from

Old World monkey Old World monkey is the common English name for a family of primates known taxonomically as the Cercopithecidae (). Twenty-four genera and 138 species are recognized, making it the largest primate family. Old World monkey genera include baboons ...

References

External links

A new primate from the Eocene Pondaung Formation of Myanmar and the monophyly of Burmese amphipithecids, by K. Christopher Beard at al., Proceedings of the Royal Society B (Biological Sciences) on July 1, 2009

Eurekalert article, by Leigh Kish
{{Taxonbar, from=Q144030 Eocene primates Prehistoric monkeys Fossil taxa described in 2009 Prehistoric primate genera Eocene mammals of Asia Fossils of Myanmar

See also

References

External links