Ganlea
Encyclopedia
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.
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 monkey
s (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. 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
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
seem to be more basal members than Ganlea. 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
s.
Primate
A primate is a mammal of the order Primates , which contains prosimians and simians. Primates arose from ancestors that lived in the trees of tropical forests; many primate characteristics represent adaptations to life in this challenging three-dimensional environment...
from central Myanmar
Myanmar
Burma , officially the Republic of the Union of Myanmar , is a country in Southeast Asia. Burma is bordered by China on the northeast, Laos on the east, Thailand on the southeast, Bangladesh on the west, India on the northwest, the Bay of Bengal to the southwest, and the Andaman Sea on the south....
, formerly known as Burma. Its age is about 38 million years, living during the late Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
epoch. Ganlea belongs to the group of anthropoids (i. e. humans, apes and monkeys), and is in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Amphipithecidae. It is older than any other known anthropoid from Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, and is the second oldest known from Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
. Its remains consist of teeth and jawbones belonging to 10 to 15 individuals found near the city of Bagan
Bagan
Bagan , formerly Pagan, is an ancient city in the Mandalay Region of Burma. Formally titled Arimaddanapura or Arimaddana and also known as Tambadipa or Tassadessa , it was the capital of several ancient kingdoms in Burma...
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
Canine tooth
In mammalian oral anatomy, the canine teeth, also called cuspids, dogteeth, fangs, or eye teeth, are relatively long, pointed teeth...
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
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:...
. 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 monkey
New World monkeys are the five families of primates that are found in Central and South America: Callitrichidae, Cebidae, Aotidae, Pitheciidae, and Atelidae. The five families are ranked together as the Platyrrhini parvorder and the Ceboidea superfamily, which are essentially synonymous since...
s (Platyrrhini) and the extinct propliopithecids. This places it firmly within Haplorrhini. Darwinius
Darwinius
Darwinius is a genus of Adapiformes, a group of basal primates from the Eocene epoch. Its only known species is Darwinius masillae, dated to 47 million years ago based on dating of the fossil site....
, a primate recently described and quickly claimed a transitional fossil
Transitional fossil
A transitional fossil is any fossilized remains of a lifeform that exhibits characteristics of two distinct taxonomic groups. A transitional fossil is the fossil of an organism near the branching point where major individual lineages diverge...
of great importance to human ancestry, is a member of the Adapiformes
Adapiformes
Adapiformes are an extinct group of primitive primates.The adapiformes radiated throughout much of the northern continental mass, reaching as far south as northern Africa and tropical Asia. The adapiformes existed from the Eocene to the Miocene epoch...
, which has recently been viewed as a transitional group between Strepsirrhini
Strepsirrhini
The clade Strepsirrhini is one of the two suborders of primates. Madagascar's only non-human primates are strepsirrhines, and others can be found in southeast Asia and Africa...
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
Human
Humans are the only living species in the Homo genus...
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
Eosimias was a genus of early primates, first discovered and identified in 1999 from fossils collected in the Shanghuang fissure-fillings of the southern Jiangsu Province, China. It is a part of the family Eosimiidae, which includes three known species: Eosimias sinensis, Eosimias centennicus, and...
seem to be more basal members than Ganlea. 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
The Old World monkeys or Cercopithecidae are a group of primates, falling in the superfamily Cercopithecoidea in the clade Catarrhini. The Old World monkeys are native to Africa and Asia today, inhabiting a range of environments from tropical rain forest to savanna, shrubland and mountainous...
s.