Ganlea

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Ganlea
Temporal range: Late Eocene
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Suborder: Haplorhini
Infraorder: Simiiformes
Family: Amphipithecidae
Genus: Ganlea
Beard et al., 2009
Species
  • G. megacaninaBeard et al., 2009 (type)

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 (i. e. humans, apes and monkeys), 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. [1]

Contents

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 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. 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 monkeys (Platyrrhini) and the extinct propliopithecids. This places it firmly within Haplorrhini. Darwinius , a primate recently described and quickly claimed a transitional fossil of great importance to human ancestry, is a member of the Adapiformes, which has recently been viewed as a transitional group between Strepsirrhini and Haplorrhini. [2] 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 humans) 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. [3] Other extinct primates such as Eosimias seem to be more basal members than Ganlea. [4] 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 monkeys.

See also

Related Research Articles

Haplorhini Suborder of primates

Haplorhini, the haplorhines or the "dry-nosed" primates, is a suborder of primates containing the tarsiers and the monkeys, as sister of the Strepsirrhini ("moist-nosed"). The name is sometimes spelled Haplorrhini. The monkeys include catarrhines, and the platyrrhines.

Simian Infraorder of primates

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 superfamilies Old World monkeys in the stricter sense (Cercopithecidae) and apes.

<i>Eosimias</i> Extinct genus of primates

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 includes three known species: Eosimias sinensis, Eosimias centennicus, and Eosimias dawsonae. It provides us with a glimpse of a primate skeleton similar to that of the common ancestor of the Haplorhini. The name Eosimias is designed to mean "dawn monkey", from Greek eos "dawn" and Latin simius "monkey".

Monkey Animal of the "higher primates" (the simians), but excluding the apes

Monkey is a common name that may refer to most mammals of the infraorder Simiiformes, also known as the simians. Traditionally, all animals in the group now known as simians are counted as monkeys except the apes, a grouping known as paraphyletic; however in the broader sense based on cladistics, apes (Hominoidea) are also included, making the terms monkeys and simians synonyms in regard of their scope. Monkeys are divided into the families of New World monkeys (Platyrrhini) and Old World monkeys.

Hsanotherium is an extinct genus of early ungulate from the middle Eocene, described in 2000 in the Pondaung Formation, Myanmar.

Altiatlasius is an extinct genus of mammal, which may have been the oldest known primate, dating to the Late Paleocene from Morocco. The only species, Altiatlasius koulchii, was described in 1990.

<i>Darwinius</i> Extinct genus of primates

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.

Karanisia is an extinct genus of strepsirrhine primate from middle Eocene deposits in Egypt.

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.

Dermotherium is a genus of fossil mammals closely related to the living colugos, a small group of gliding mammals from Southeast Asia. Two species are recognized: D. major from the Late Eocene of Thailand, based on a single fragment of the lower jaw, and D. chimaera from the Late Oligocene of Thailand, known from three fragments of the lower jaw and two isolated upper molars. In addition, a single isolated upper molar from the Early Oligocene of Pakistan has been tentatively assigned to D. chimaera. All sites where fossils of Dermotherium have been found were probably forested environments and the fossil species were probably forest dwellers like living colugos, but whether they had the gliding adaptations of the living species is unknown.

<i>Khoratpithecus</i> Extinct genus of primates

Khoratpithecus is an extinct genus of pongin primates that lived during the late Miocene in Myanmar and Thailand.

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).

<i>Afrasia djijidae</i> Eocene fossil primate from Myanmar

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.

Plesiopithecus is an extinct genus of early strepsirrhine primate from the late Eocene.

<i>Afrotarsius</i> Extinct genus of primates

Afrotarsius is a primate found in the Paleogene of Africa.

<i>Amphipithecus</i> Extinct genus of primates

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).

This paleomammalogy list records new fossil mammal taxa that were described during the year 2009, as well as notes other significant paleomammalogy discoveries and events which occurred during that year.

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.

References

  1. Beard, KC; Marivaux, L; Chaimanee, Y; Jaeger, JJ; Marandat, B; Tafforeau, P; Soe, AN; Tun, ST; K. Christopher Beard, Laurent Marivaux, Yaowalak Chaimanee, Jean-Jacques Jaeger, Bernard Marandat, Paul Tafforeau, Aung Naing Soe, Soe Thura Tun and Aung Aung Kyaw (2009). "A new primate from the Eocene Pondaung Formation of Myanmar and the monophyly of Burmese amphipithecids". Proceedings of the Royal Society B. 276 (1671): 3285–3294. doi:10.1098/rspb.2009.0836. PMC   2817178 . PMID   19570790.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. Franzen, Jens L.; et al. (2009). Hawks, John (ed.). "Complete Primate Skeleton from the Middle Eocene of Messel in Germany: Morphology and Paleobiology". PLoS ONE . 4 (5): e5723. Bibcode:2009PLoSO...4.5723F. doi: 10.1371/journal.pone.0005723 . PMC   2683573 . PMID   19492084.
  3. "Ganlea on scienceblog.com, by Brian Switek". Archived from the original on 2009-07-06. Retrieved 2009-07-01.
  4. The description of Eosimias by Beard et al. in 1994 can be seen as the beginning of the recent debate on the Asian ancestry of anthropoids