Ardipithecus

Ardipithecus is a genus of very early hominid. It is the earliest known genus of the family Hominidae, which includes humans but not great apes. 

Ardipithecus lived during the late Neogene period, in the Afar Depression in Ethiopia. It is now extinct.

The genus Ardipithecus includes two known species. The first is Ardipithecus kadabba, which lived from around 5.8 million to 5.2 million years ago. The second is Ardipithecus ramidus, which lived from about 5.8 million to 4.4 million years ago. 

Scientists think Ar. kadabba evolved into Ar. ramidus,Lovejoy, C. O. (2014). "Ardipithecus and Early Human Evolution in Light of Twenty-First-Century Developmental Biology". Journal of Anthropological Research. 70 (3): 337–363. doi:10.3998/jar.0521004.0070.301. JSTOR 24394231. S2CID 84197134. and Ardipithecus evolved into Australopithecus.

 Ardipithecus kadabba 
See the main page: Ardipithecus kadabba

This species (abbreviated Ar. kadabba) is the older of the two Ardipithecus species. However, it was discovered after Ar. ramidus was. Ar. kadabba lived from around 5.8 million to 5.2 million years ago.

At first, scientists thought Ar. kadabba fossils came from a subspecies of Ar. ramidus. Later, they concluded that Ar. kadabba was its own unique species, not a subspecies of Ar. ramidus.Haile-Selassie, Y.; Suwa, G.; White, Timothy Douglas (2004). "Late Miocene Teeth from Middle Awash, Ethiopia, and Early Hominid Dental Evolution". Science. 303 (5663): 1503–1505. Bibcode:2004Sci...303.1503H. doi:10.1126/science.1092978. PMID 15001775. S2CID 30387762. Scientists also learned that Ar. kadabba came before Ar. ramidus and was probably its ancestor.

Ar. kadabba may have been bipedal. Their bodies and brains were probably a similar size to modern chimpanzees'.

 Ardipithecus ramidus 
See the main page: Ardipithecus ramidusthumb|Drawing of an Ardipithecus using a rock to crack nuts, like chimpanzees doPaleoanthropologists have found fossils from at least 44 Ar. ramidus individuals in the Afar Depression. These fossils were dated to between 4.32 and 4.51 million years ago.Semaw, S.; Simpson, S. W.; et al. (2005). "Early Pliocene hominids from Gona, Ethiopia" (PDF). Nature. 433 (7023): 301–305. Bibcode:2005Natur.433..301S. doi:10.1038/nature03177. PMID 15662421. S2CID 4431031.

Ar. ramidus could walk upright or live in trees.White, Timothy Douglas; Asfaw, B.; Beyene, Y.; Haile-Selassie, Y.; Lovejoy, C. O.; Suwa, G.; WoldeGabriel, G. (2009). "Ardipithecus ramidus and the Paleobiology of Early Hominids". Science. 326 (5949): 75–86. Bibcode:2009Sci...326...75W. doi:10.1126/science.1175802. PMID 19810190. S2CID 20189444.Lovejoy, C. O.; Latimar, B.; Suwa, G.; Asfaw, B.; White, Timothy Douglas (2011). "Combining Prehension and Propulsion: The Foot of Ardipithecus ramidus" (PDF). Science. 326 (5949): 72–72e8. doi:10.1126/science.1175832. PMID 19810198. S2CID 26778544.Lovejoy, C. O. (2014). "Ardipithecus and Early Human Evolution in Light of Twenty-First-Century Developmental Biology". Journal of Anthropological Research. 70 (3): 337–363. doi:10.3998/jar.0521004.0070.301. JSTOR 24394231. S2CID 84197134.Lovejoy, C. O.; Latimar, B.; Suwa, G.; Asfaw, B.; White, Timothy Douglas (2011). "Combining Prehension and Propulsion: The Foot of Ardipithecus ramidus" (PDF). Science. 326 (5949): 72–72e8. doi:10.1126/science.1175832. PMID 19810198. S2CID 26778544. It probably spent a lot of time in the trees and could not walk on two feet for very long.White, T. D.; Lovejoy, C. O.; Asfaw, B.; Carlson, J. P.; Suwa, G. (2015). "Neither chimpanzee nor human, Ardipithecus reveals the surprising ancestry of both". Proceedings of the National Academy of Sciences of the United States of America. 112 (16): 4877–4884. Bibcode:2015PNAS..112.4877W. doi:10.1073/pnas.1403659111. PMC 4413341. PMID 25901308. It would have been less efficient at running and walking than members of Australopithecus or Homo. Still, its ability to walk on two feet makes it extremely important to human evolution. 

Their bodies and brains were about the same size as modern chimpanzees. 

 Evolution 
Ardipithecus was probably the ancestor of Australopithecus. Ardipithecus had bipedalism and reduced canines, like the Australopithecines. It was less aggressive than chimpanzees and may have looked like bonobos.Suwa, Gen; Sasaki, Tomohiko; Semaw, Sileshi; Rogers, Michael J.; Simpson, Scott W.; Kunimatsu, Yutaka; Nakatsukasa, Masato; Kono, Reiko T.; Zhang, Yingqi; Beyene, Yonas; Asfaw, Berhane; White, Tim D. (2021-12-07). "Canine sexual dimorphism in Ardipithecus ramidus was nearly human-like". Proceedings of the National Academy of Sciences. 118 (49) e2116630118. Bibcode:2021PNAS..11816630S. doi:10.1073/pnas.2116630118. ISSN 0027-8424. PMC 8670482. PMID 34853174. 

Ardipithecus shares several traits with the African great ape genera (Pan and Gorilla). Some scientists think it may be more closely related to these genera than to humans. 

 Related pages 
 Human timeline

 References 

Category:Australopithecines