Title of Presentation

“Honing in on human and African ape origins: hypothesis building and testing with the fossil record”

The scientific pursuit of human origins started with Darwin’s theory of evolution. The first pre-modern human ancestor to be recognized was Neaderthal man, followed by earlier Homo erectus and Australopithecus. From the later 1990s to the early 2000s, the hypothesis that the human and ape lineages diverged around 5 million years ago came to be considered most probable, Australopithecus emerging by 4 million years ago and subsequently leading to genus Homo. Furthermore, the genomic differences between living African apes and humans were determined to be slight, and hence leading to the sometimes unstated perception of an African ape-like, and in particular a chimpanzee-like, ancestry of the human lineage. At the same time, the recent decades have seen a steady accumulation of fossils relevant to the understanding of human origins. These fossils are enabling the formation of testable hypotheses regarding actual patterns of modern African ape and human emergences. The fossil record is always sparse and far from sufficient, but constitutes direct evidence of actual evolutionary history. Hence, the challenge to correctly decode this limited material evidence must be taken up. In this presentation, we show examples of hypothesis building and testing pertaining to human origins based on the fossil record as exemplified by research on 4.4 million-year-old Ardipithecus ramidus and close to 10 million-year-old Chororapithecus abyssinicus.

Profile

Web Site URL

http://www.um.u-tokyo.ac.jp/people/faculty_suwa.htm

A brief Biography

Born in 1954. Graduated from the Department of Biology, Faculty of Science, The University of Tokyo in 1978. In 1980, master degree in biological anthropology, Graduate Division of Science, The University of Tokyo, continued to doctoral course, and then concurrently entered the Graduate School the University of California at Berkeley. Research on early hominid fossils were initiated at the latter institution, Ph.D. (U.C. Berkeley) in 1990. From 1988, assistant professor, Primate Research Institute, Kyoto University. From 1991 lecturer and 1994 associate professor at the Faculty of Science, The University of Tokyo. From 2006 to present, professor at the University Museum, The University of Tokyo.

My research primarily involves elucidating the evolutionary history of humans and their ancestors by means of the fossil record. Since the 1980s, field research in Ethiopia and descriptive and comparative analyses of the recovered fossils (both human ancestors and other mammals) form the basis of my research. Analytical and interpretive research includes those on the dentition, skull and postcranium, in part via pioneering application of micro-ct based morphological analysis.

Discoveries and collaborative research include those on the early Acheulean (handaxe) assemblages and Homo erectus and Australopithecus fossils (mostly in the 1990s), the first fossils of Ardipithecus ramidus (1992), and analysis of the Ardipithecus ramidus partial skeleton and related fossils (2009). Since 2006, field work is ongoing at a research area that exposes circa 10 million year old sediments, which has led to the discovery and naming of Chororapithecus abyssinicus (2007), a probable close relative of the gorilla.

Details of selected Awards and Honors

2010	Asahi Prize: research related to the earliest stages of human evolution including Ardipithecus ramidus
2011	Foreign Minister’s Commendation: promotion of academic exchange in Ethiopia through anthropology
2011	The Award of the Anthropological Society of Nippon: contributions to the paleobiology of human ancestors older than the australopithecine grade of human evolution
2012	Eminent Evolutionalist Award, Society of Evolutionary Studies Japan: discovery and analysis of significant paleoanthropological fossils

A list of selected Publications

・White TD, Lovejoy CO, Asfaw B, Carlson J, Suwa G (2015) Neither chimpanzee nor human, Ardipithecus reveals the surprising ancestry of both. Proceedings of the National Academy of Sciences USA (in press)

・Suwa G, Beyene Y, Asfaw B (2014) The Konso-Gardula Research Project: Paleontological Collections Volume 1: Background and Fossil Aves, Cercopithecidae and Suidae. The University Museum, The University of Tokyo, Bulletin No. 47, 125 pp.

・Beyene Y, Katoh S, WoldeGabriel G, Hart WK, Uto K, Sudo M, Kondo M, Hyodo M, Renne PR, Suwa G, Asfaw B (2013) The characteristics and chronology of the earliest Acheulean at Konso, Ethiopia. Proceedings of the National Academy of Sciences USA 110: 1584-1591.

・Suwa G, Kono RT, Simpson S, Asfaw B, Lovejoy CO, White TD (2009) Paleobiological implications of the Ardipithecus ramidus dentition. Science 326: 94-99.

・Suwa G, Asfaw B, Kono RT, Kubo D, Lovejoy CO, White TD (2009) The Ardipithecus ramidus skull and its implications for hominid origins. Science 326: 68e1-e7.

・Lovejoy CO, Suwa G, Simpson S, Matternes JH, White TD (2009) The great divides: Ardipithecus ramidus reveals the postcrania of our last common ancestors with African apes. Science 326: 100-106.

・White TD, Asfaw B, Beyene Y, Haile-Selassie Y, Lovejoy CO, Suwa G, WoldeGabriel G (2009) Ardipithecus ramidus and the paleobiology of early hominids. Science 326: 75-86.

・Suwa G, Kono RT, Katoh S, Asfaw B, Beyene Y (2007) A new species of great ape from the late Miocene epoch in Ethiopia. Nature 448: 921-924.

・Suwa G, Asfaw B, Haile-Selassie Y, White T, Katoh S, WoldeGabriel G, Hart WK, Nakaya H, Beyene Y (2007) Early Pleistocene Homo erectus fossils from Konso, southern Ethiopia. Anthropological Science 115: 133-151.

・Suwa G, Kono RT (2005) A micro-CT based study of linear enamel thickness in the mesial cusp section of human molars: reevaluation of methodology and assessment of within-tooth, serial, and individual variation. Anthropological Science 113: 273-289.

・Suwa G, Nakaya H, Asfaw B, Saegusa H, Amzaye A, Kono RT, Beyene Y, Katoh S (2003) Plio-Pleistocene terrestrial mammal assemblage from Konso, southern Ethiopia. Journal of Vertebrate Paleontology 23: 901-916.

・Suwa G, Asfaw B, Beyene Y, White TD, Katoh S, Nagaoka S, Nakaya H, Uzawa K, Renne P, WoldeGabriel G (1997) The first skull of Australopithecus boisei. Nature 389: 489-492.

・Suwa G, White T, Howell FC (1996) Mandibular postcanine dentition from the Shungura Formation, Ethiopia: crown morphology, taxonomic allocations, and Plio-Pleistocene hominid evolution. American Journal of Physical Anthropology 101: 247-282.

・White TD, Suwa G, Asfaw B (1994) Australopithecus ramidus, a new species of early hominid from Aramis, Ethiopia. Nature 371: 306-312.

・Suwa G (1988) Evolution of the “robust” australopithecines in the Omo succession: evidence from mandibular premolar morphology. In: Grine F (ed.) The Evolutionary History of the Robust Australopithecines. New York: Aldine, pp: 199-222.