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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/321660247 On the origin of modern humans: Asian perspectives Article in Science · December 2017 DOI: 10.1126/science.aai9067 CITATIONS READS 34 1,406 3 authors, including: Katerina Douka Michael D. Petraglia Max Planck Institute for the Science of Human History Max Planck Institute for the Science of Human History 109 PUBLICATIONS 2,785 CITATIONS 231 PUBLICATIONS 4,872 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: Yacimiento paleolítico y mesolítico de la Cueva de El Cierro (Ribadesella, Asturias, España) / Palaeolithic and Mesolithic site of El Cierro Cave (Ribadesella, Asturias, Spain) View project Vertebrate Paleontology of the Arabian Peninsula View project All content following this page was uploaded by Katerina Douka on 30 May 2018. The user has requested enhancement of the downloaded file. RESEARCH ◥ on a somewhat regular basis. New finds of REVIEW SUMMARY H. sapiens fossils, with increasingly secure dating associations, are emerging in different areas of Asia, some seemingly from the first half of PALEOANTHROPOLOGY the Late Pleistocene. Cultural variability dis- cerned from archaeological studies indicates On the origin of modern humans: that modern human behaviors did not simply ◥ spread across Asia in a ON OUR WEBSITE time-transgressive pat- Asian perspectives Read the full article tern. This regional varia- at http://dx.doi. tion, which is particularly Christopher J. Bae,* Katerina Douka,* Michael D. Petraglia* org/10.1126/ distinct in Southeast Asia, science.aai9067 could be related at least .................................................. in part to environmental BACKGROUND: The earliest fossils of Homo departure points, even during glacial stages and ecological variation (e.g., Palearctic versus sapiens are located in Africa and dated to the late when sea levels would have been much lower. Oriental biogeographic zones). Middle Pleistocene. At some point later, modern Moreover, what role did major climatic fluc- humans dispersed into Asia and reached the far- tuations and environmental events (e.g., the OUTLOOK: Recent findings from archaeology, away locales of Europe, Australia, and eventually Toba volcanic super-eruption) play in the dis- hominin paleontology, geochronology, and ge- the Americas. Given that Neandertals, Denisovans, persal of modern humans across Asia? Did ex- netics indicate that the strict “out of Africa” Downloaded from mid-Pleistocene Homo,andH. floresiensis were tirpations of groups occur regularly, and did model, which posits that there was only a single present in Asia before the appearance of mod- extinctions of populations take place? Questions dispersal into Eurasia at ~60,000 years ago, is ern humans, the timing and nature of the spread such as these are paramount in understanding in need of revision. In particular, a multiple- of modern humans across Eurasia continue to hominin evolution and Late Pleistocene Asian dispersal model, perhaps beginning at the be subjects of intense debate. For instance, did paleoanthropology. advent of the Late Pleistocene, needs to be ex- modern humans replace the indigenous popu- amined more closely. An increasingly robust http://science.sciencemag.org/ lations when moving into new regions? Alterna- ADVANCES: An increasing number of multi- record from Late Pleistocene Asian paleoan- tively, did population contact and interbreeding disciplinary field and laboratory projects focused thropology is helping to build and establish occur regularly? In terms of behavior, did tech- on archaeological sites and fossil localities from new views about the origin and dispersal of nological innovations and symbolism facilitate different areas of Asia are producing impor- modern humans.▪ dispersals of modern humans? For example, it tant findings, allowing researchers to address is often assumed that only modern humans were key evolutionary questions that have long per- capable of using watercraft and navigating to plexed the field. For instance, technological The list of author affiliations can be found in the full article online. distant locations such as Australia and the advances have increased our ability to success- *Corresponding author. Email: [email protected] (C.J.B.); — [email protected] (K.D.); [email protected] (M.D.P.) Japanese archipelago destinations that would fully collect ancient DNA from hominin fossils, Cite this article as C. J. Bae et al., Science 358, eaai9067 not have been visible to the naked eye from the providing proof that interbreeding occurred (2017). DOI: 10.1126/science.aai9067 on December 7, 2017 Map of sites with ages and postulated early and later pathways associated with modern humans dispersing across Asia during the Late Pleistocene. Regions of assumed genetic admixture are also shown. ka, thousand years ago. Bae et al., Science 358, 1269 (2017) 8 December 2017 1of1 RESEARCH ◥ cifically, how the Asian record contributes to ad- REVIEW dressing such questions. The big questions PALEOANTHROPOLOGY Findings from archaeology, hominin paleontology, geochronology, genetics, and paleoclimatology have all been contributing to a better understand- On the origin of modern humans: ing of the Late Pleistocene human evolutionary record in Asia. Here we discuss some of the big questions that paleoanthropologists are investi- Asian perspectives gating across Asia: Can modern human dispersal 1 2,3 2,4 out of Africa be considered a single event occurring Christopher J. Bae, * Katerina Douka, * Michael D. Petraglia * only after 60 ka, or is the picture more compli- cated? By which route(s) did modern humans dis- “ ” Homo sapiens The traditional out of Africa model, which posits a dispersal of modern perse across Asia? What was the nature of the across Eurasia as a single wave at ~60,000 years ago and the subsequent replacement of interactions between modern humans and hominin all indigenous populations, is in need of revision. Recent discoveries from archaeology, groups already present in Asia? What role did hominin paleontology, geochronology, genetics, and paleoenvironmental studies have geographic and/or paleoenvironmental variations contributed to a better understanding of the Late Pleistocene record in Asia. Important play in modern human dispersals? findings highlighted here include growing evidence for multiple dispersals predating 60,000 years ago in regions such as southern and eastern Asia. Modern humans moving into Can the modern human dispersal be Downloaded from Asia met Neandertals, Denisovans, mid-Pleistocene Homo, and possibly H. floresiensis,with considered a single event occurring only some degree of interbreeding occurring.These early human dispersals, which left at least some after 60 ka? genetic traces in modern populations, indicate that later replacements were not wholesale. Variations of the “out of Africa” (OoA) model may be broadly categorized as follows: (i) a single dis- he origin of modern humans has long per- of the latter trait among the recently reported persal occurring during marine isotope stage plexed us. As the well-known paleoanthro- early modern human fossils from Jebel Irhoud, (MIS) 5; (ii) multiple dispersals beginning dur- http://science.sciencemag.org/ pologist William Howells remarked more Morocco (5, 6), it may be possible that it devel- ing MIS 5; (iii) a single dispersal occurring dur- T than four decades ago [(1), p. 477], “That oped much more recently, only within the past ing MIS 3; and (iv) multiple dispersals beginning part of human history covering the emer- 130,000 years. during MIS 3. We detail each of these broadly de- gence of modern man and his regional differ- Some of the earliest morphologically modern fined models below, but we begin with the single- entiation continues to be surprisingly obscure. humans are reported from the sites Omo Kibish, dispersal MIS 3 iteration because it has received Locations of some elements of agreement or con- dating to ~195 thousand years ago (ka) (7), and the greatest attention, followed by the multiple- troversy…have long been clear, but the dimensions Herto, dating to ~160 ka (8), both located in the dispersal MIS 5 model. of the whole problem are far from obvious. The Horn of Africa (Fig. 1A). These fossils have been trees are familiar, but the forest is not.” used for the past several decades to support an Single dispersal during MIS 3 Perhaps the primary reason for this is that East African origin for modern humans, corrobo- The traditional OoA model proposes that a single 9–11 there has been no universal consensus on the traits rating similar findings from genetic studies ( ). major dispersal event of modern humans out of on December 7, 2017 that make us human. Arguments for a large cra- Yet the recent discovery of modern human fossils Africa and into Eurasia occurred some time after nial capacity defining our species went by the from Jebel Irhoud dating to ~310 ka (5, 12)raises 60 to 50 ka (15). In this model, earlier dispersals wayside with the realization that Neandertals, important questions about the singular role of by anatomically modern humans into the Levant whose cranial capacity is slightly larger than ours East Africa in the genesis of modern human mor- (e.g., Qafzeh and Skhul) were minor in scale and, on average, were not actually Cossack soldiers phology. Further, questions exist about whether for all intents and purposes, evolutionary dead or pathological