Heliopithecus
Encyclopedia
Heliopithecus is an extinct genus
of primate
s that existed 16 million years ago during the Miocene
epoch. Fragmentary fossil remains of a jaw
and isolated teeth were found in Saudi Arabia
which have been described as belonging to H. leakeyi. Some authors regard Heliopithecus as synonymous with Afropithecus
.
and four isolated teeth were unearthed in Ad Dabtiyah, Saudi Arabia
in 1978 and were named by Andrews and Martin in 1987. It was assigned to Afropithecini
by Andrews in 1992 and later reassigned to Proconsulidae
in 2010 by Zalmout et.al.
with parallel toothrows. The upper premolars are larger as compared to molars, with the upper molars being slightly wider than longer. The teeth of the upper cheek are low-crowned with thick enamel.
- a view supported by Richard Leakey
. Similarity between these genera include large upper premolars, and narrow upper molars "with reduced development of lingual cingulum
and more bunodont cusps
." However, the general view held is that Heliopithecus is separate from and more primitive than Afropithecus and Morotopithecus. This view is supported by the fact that Heliopithecus has broader cheek teeth and a better developed lingual cingulum as compared to Afropithecus. Heliopithecus differs from Morotopithecus in that it has a narrower palate and upper cheek teeth and a better developed lingual cingulum.
As compared to other Early Miocene Proconsuloids, Heliopithecus has more powerful teeth and jaws, these features may have played a key role in the spread of Hominoids from Africa
into Eurasia
, 17 million years ago - a time when lower sea levels resulted in the Arabian Peninsula
being directly connected to East Africa
.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of primate
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...
s that existed 16 million years ago during the Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
epoch. Fragmentary fossil remains of a jaw
Jaw
The jaw is any opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food. The term jaws is also broadly applied to the whole of the structures constituting the vault of the mouth and serving to open and close it and is part of the body plan of...
and isolated teeth were found in Saudi Arabia
Saudi Arabia
The Kingdom of Saudi Arabia , commonly known in British English as Saudi Arabia and in Arabic as as-Sa‘ūdiyyah , is the largest state in Western Asia by land area, constituting the bulk of the Arabian Peninsula, and the second-largest in the Arab World...
which have been described as belonging to H. leakeyi. Some authors regard Heliopithecus as synonymous with Afropithecus
Afropithecus
Afropithecus turkanensis, a new Miocene hominoid, was excavated from a small site near Lake Turkana called Kalodirr in northern Kenya in 1986 and was named by Richard Leakey and Meave Leakey...
.
Discovery and classification
Fragmentary fossil remains of a left maxillaMaxilla
The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...
and four isolated teeth were unearthed in Ad Dabtiyah, Saudi Arabia
Saudi Arabia
The Kingdom of Saudi Arabia , commonly known in British English as Saudi Arabia and in Arabic as as-Sa‘ūdiyyah , is the largest state in Western Asia by land area, constituting the bulk of the Arabian Peninsula, and the second-largest in the Arab World...
in 1978 and were named by Andrews and Martin in 1987. It was assigned to Afropithecini
Afropithecus
Afropithecus turkanensis, a new Miocene hominoid, was excavated from a small site near Lake Turkana called Kalodirr in northern Kenya in 1986 and was named by Richard Leakey and Meave Leakey...
by Andrews in 1992 and later reassigned to Proconsulidae
Proconsulidae
The Proconsulidae are an early family of primates that lived during the Miocene epoch in Kenya, and was restricted to Africa. The family is split into two subfamilies....
in 2010 by Zalmout et.al.
Description of fossil remains
The maxilla is characterized with a shallow and narrow palatePalate
The palate is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but, in most other tetrapods, the oral and nasal cavities are not truly separate. The palate is divided into two parts, the anterior...
with parallel toothrows. The upper premolars are larger as compared to molars, with the upper molars being slightly wider than longer. The teeth of the upper cheek are low-crowned with thick enamel.
Differences from sister genera
From studies conducted on the dental characteristics of Heliopithecus, it has been suggested by Andrews and Martin, that Heliopithecus may be synonymous with Afropithecus and MorotopithecusMorotopithecus
Morotopithecus bishopi is a species of fossil ape discovered in Moroto, Uganda.The phylogenetic status of Morotopithecus bishopi is debated to the extent that it challenges established views on the connection between Miocene primates and extant hominids...
- a view supported by Richard Leakey
Richard Leakey
Richard Erskine Frere Leakey is a politician, paleoanthropologist and conservationist. He is second of the three sons of the archaeologists Louis Leakey and Mary Leakey, and is the younger brother of Colin Leakey...
. Similarity between these genera include large upper premolars, and narrow upper molars "with reduced development of lingual cingulum
Dental anatomy
Dental anatomy is a field of anatomy dedicated to the study of human tooth structures. The development, appearance, and classification of teeth fall within its purview. Tooth formation begins before birth, and teeth's eventual morphology is dictated during this time...
and more bunodont cusps
Dental anatomy
Dental anatomy is a field of anatomy dedicated to the study of human tooth structures. The development, appearance, and classification of teeth fall within its purview. Tooth formation begins before birth, and teeth's eventual morphology is dictated during this time...
." However, the general view held is that Heliopithecus is separate from and more primitive than Afropithecus and Morotopithecus. This view is supported by the fact that Heliopithecus has broader cheek teeth and a better developed lingual cingulum as compared to Afropithecus. Heliopithecus differs from Morotopithecus in that it has a narrower palate and upper cheek teeth and a better developed lingual cingulum.
As compared to other Early Miocene Proconsuloids, Heliopithecus has more powerful teeth and jaws, these features may have played a key role in the spread of Hominoids 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...
into Eurasia
Eurasia
Eurasia is a continent or supercontinent comprising the traditional continents of Europe and Asia ; covering about 52,990,000 km2 or about 10.6% of the Earth's surface located primarily in the eastern and northern hemispheres...
, 17 million years ago - a time when lower sea levels resulted in the Arabian Peninsula
Arabian Peninsula
The Arabian Peninsula is a land mass situated north-east of Africa. Also known as Arabia or the Arabian subcontinent, it is the world's largest peninsula and covers 3,237,500 km2...
being directly connected to East Africa
East Africa
East Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:...
.