Eske Willerslev

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Eske Willerslev
Willerslev.png
Eske Willerslev in the laboratory.
Born (1971-06-05) 5 June 1971 (age 45)
Gentofte
Nationality Danish
Fields Evolutionary biologists
Institutions University of Copenhagen
Known for Ancient DNA

Eske Willerslev (born 5 June 1971) is a Danish evolutionary geneticist notable for his pioneering work in molecular anthropology, palaeontology, and ecology. He currently holds the Prince Philip Professorship in Ecology and Evolution at University of Cambridge, UK and the Lundbeck Foundation Professorship in Evolution at Copenhagen University, Denmark. He is director of the Centre of Excellence in GeoGenetics, a research associate at the Wellcome Trust Sanger Institute, and a Professorial Fellow at St John's College, Cambridge. He is the son of historian Richard Willerslev and twin brother of anthropologist Rane Willerslev.

Biography[edit]

Before becoming a scientist Willerslev led several expeditions in Siberia in the early 1990s with his twin brother, anthropologist Rane Willerslev collecting ethnographic materials and megafauna skeleton remains that are stored at Moesgaard Museum in Denmark (the largest Siberian ethnographical collection in Denmark). Willerslev also lived as a fur trapper in the Sakha (Yakutia) Republic from 1993–94.[1][2] Willerslev handed in his PhD thesis as a doctor thesis and obtained his DSc at Copenhagen University in 2004.[3] He moved to Oxford University as an independent Wellcome Trust Fellow, and became full professor at Copenhagen University at the age of 33. In 2015 Willerslev took up the Prince Philip Chair in Ecology and Evolution at the Department of Zoology at University of Cambridge. Willerslev is a Foreign Associate Member of The National Academy of Sciences (USA),[4] elected member of the Royal Danish Academy of Sciences and Letters,[5] and Honorary Doctor at University of Oslo.[6] He has been a visiting professor at Oxford University, UK, and a Visiting Miller Professor at UC Berkeley. In 2014, he became an adopted member of the Crow Tribe in Montana (Apsaalooke), where he carries the name ChiitdeeXia’ssee (Well Known Scout).[7]

He has received several awards including the Antiquity Prize for the best paper in the journal Antiquity in 2009, the Danish Independent Research Council's Major EliteForsk Prize,[8] the Rosenkjær Award[9] and the Genius Award (Geniusprisen) of Danish Science journalists for "an impressive array of research successes in the public eye, combined with a unique tour-de-force through university".[10][11]

Research[edit]

Environmental DNA[edit]

During his MSc project Willerslev and colleagues were the first to obtain ancient DNA directly from ice cores.[12] Later, Willerslev and his team expanded on this approach and was the first to show that DNA from plants, mammals and birds can be obtained directly from environmental samples (environmental DNA) ancient as well as modern.[13] He later showed that environmental DNA can also be obtained from a variety of settings including basal ice and revealed a forested Greenland some 400,000 years ago questioning if southern Greenland was ice free during the last interglacial.[14][15] His team has also used environmental DNA to reveal forested refugia in Scandinavia during the last interglacial,[16] and that forbs rather than grasses were dominating the steppe environments of the northern hemisphere during the Pleistocene and was an important food source for the megafauna.[17]

Using environmental DNA, Willerslev and collaborators estimated that woolly mammoth in mainland Alaska survived more than 3,500 years earlier than previously thought, thereby dismissing the Blitzkrieg and Impact hypotheses for megafauna extinction.[18] They also clarified the importance of climate change as a driver of megafauna population dynamics,[19] and the decline of protein rich forbs during the Pleistocene extinctions.[20]

First ancient human genome[edit]

In 2010, a team led by Willerslev sequenced the genome of a 4,000-year-old man from the Saqqaq culture of Greenland from his hair. This was the first ancient human genome to be sequenced. The DNA obtained from the hair was fragmented into an average size of 55 base pairs.[21][22] They revealed that the Saqqaq peoples represent a migration from Siberia to the Americas that is separate from that of Native American and Inuit ancestors. In 2014 his team showed that all paleoeskimos in the New World representing several distinct cultures all belonged to the same population as the Saqqaq man and that they lived in genetic isolation from Native Americans for almost 5,000 years before they died out some 700 years ago.[23] This was the first genetic evidence for cultural change happening in isolation through the spread of ideas within a population rather than through meetings between different groups of peoples as seen e.g. during the European Neolithisation.

Early peopling of the Americas[edit]

In 2008 Willerslev led the DNA study on coprolites from the Paisley Caves in Oregon showing human presence in North America more than 14,000 years ago and some 1000 years prior to Clovis.[24]

In 2013 his team discovered a genetic link between western Eurasians and Native Americans by sequencing the genome of the 24,000-year-old Mal´ta boy from central Siberia, showing that all contemporary Native Americans carry approximately 1/3 of their genome from the Mal’ta population.[25]

In 2014 his team sequenced the Clovis-age genome from the 12,600-year-old Anzick boy from Montana and found it to be ancestral to many contemporary Native Americans thereby rejecting the Solutrean theory for early peopling of the Americas.[26] The skeleton of the boy was later reburied by the support of Willerslev and this event facilitated his adoption into the Crow tribe.[27]

In 2015 Willerslev’s team sequenced the genome of the Kennewick Man, a ca. 8,500 year old skeleton whose origin have been heavy debated. The DNA analyses showed Kennewick to be closer related to Native Americans than to any other contemporary groups and rejecting claims of Kennewick Man being closely related to Japanese Ainu or Europeans.[28]

Peopling of Australia[edit]

In 2011 Willerslev’s team sequenced the first Aboriginal Australian genome from an historically ancient tuft of hair.[29] The study revealed that Aboriginal Australians diversified from the Africans some 20-30 thousand years prior to the evolutionary split between Europeans and Asians. Secondary gene flow has resulted in Aboriginal Australians being closer related to Asians than to Europeans.

Early peopling of Europe[edit]

Willerslev’s team sequenced the genome of one of the earliest anatomically modern humans from Europe, Kostinki 14 from Russia dated to be between 36-38,000 years old.[30] The results show that most of the major genetic components present in Europeans today was present in Europe from early on. In 2014 his team undertook the first large scale past population genomic study reporting more than 100 ancient genomes from Bronze Age Euope and Asia.[31] They found that lactose tolerance that is common in northern Europe today was not common even as late as 2,000 years ago. They also found evidence for major populations movements and replacements in both Europe and Asia during the Bronze Age time and that significant parts of contemporary European and Asian genetic diversity was created during this period. They later showed that plague was a likely driver of Bronze Age population dynamics, which as of 2015 is the oldest genomes of Yersinia pestis (the etiological agent of plague) reported.[32]

Other research[edit]

Willerslev also led a study showing that living bacteria can take up ancient DNA by natural transformation allowing for genomic recycling of ancient genetic traits,[33] and another study showing the survival of bacteria cells in permafrost for about 1/2 million years.[34]

Willerslev and collaborators have sequenced the genome of a 700,000-year-old horse from Yukon in Canada, which as of 2016 is the oldest genome ever sequenced.[35]

References[edit]

  1. ^ Fra pelsjæger til Professor. science.ku.dk. 2 June 2008
  2. ^ Eske Willerslev: Han gør det døde levende
  3. ^ Willerslev E. (2004) Recovery and analysis of ancient DNA from ice, sediments, and fossil remains. DSc thesis University of Copenhagen 2004 pp. 1–346, HCØ tryk, University of Copenhagen, Denmark
  4. ^ "Eske Willerslev". Retrieved 7 October 2014. 
  5. ^ "VIDENSKABERNES SELSKAB". Retrieved 7 October 2014. 
  6. ^ "Ancient and environmental DNA studies – Centre for Ecological and Evolutionary Synthesis". Retrieved 7 October 2014. 
  7. ^ "For Crow-indianerne er han »Well-known Wolf«". www.b.dk. Retrieved 7 October 2014. 
  8. ^ "Eske Willerslev — EliteForsk". Retrieved 7 October 2014. 
  9. ^ "Rosenkjær-foredrag med Eske Willerslev". dr.dk. 12 September 2013. 
  10. ^ cawa (16 June 2009). "DNA-forsker Eske Willerslev fik hæderspris". Retrieved 7 October 2014. 
  11. ^ "Geniusprisen". Retrieved 7 October 2014. Eske Willerslev har en imponerende række af formidlingssucceser i offentligheden bag sig kombineret med en enestående tour-de-force gennem universitetsverdenen [...] Begge har beriget Danmark med formidling af højeste karat og Danske Videnskabsjournalister er stolte af at kunne hædre de to forskere. 
  12. ^ Willerslev, E; Hansen, AJ; Christensen, B; Steffensen, JP; Arctander, P (1999). "Diversity of Holocene life-forms in fossil glacier ice". Proc. Natl. Acad. Sci. USA 96: 8017–8021. doi:10.1073/pnas.96.14.8017. 
  13. ^ Willerslev, E.; Hansen, Anders J.; Binladen, Jonas; Brand, Tina B.; Gilbert, M. Thomas P.; Shapiro, Beth; Bunce, Michael; Wiuf, Carsten; Gilichinsky, David A.; Cooper, Alan (2003). "Diverse Plant and Animal Genetic Records from Holocene and Pleistocene Sediments". Science 300 (5620): 791–5. doi:10.1126/science.1084114. PMID 12702808. 
  14. ^ Willerslev, E.; Cappellini, E.; Boomsma, W.; Nielsen, R.; Hebsgaard, M. B.; Brand, T. B.; Hofreiter, M.; Bunce, M.; Poinar, H. N.; Dahl-Jensen, D.; Johnsen, S.; Steffensen, J. P.; Bennike, O.; Schwenninger; Nathan, R.; Armitage, S.; Hoog, De; Alfimov, V.; Christl, M.; Beer, J.; Muscheler, R.; Barker, J.; Sharp, M.; Penkman, K. E. H.; Haile, J.; Taberlet, P.; Gilbert, M. T. P.; Casoli, A.; Campani, E.; Collins, M. J. (2007). "Ancient Biomolecules from Deep Ice Cores Reveal a Forested Southern Greenland". Science 317 (5834): 111–4. doi:10.1126/science.1141758. PMC 2694912. PMID 17615355. 
  15. ^ PROFILE: ESKE WILLERSLEV: Ancient DNA's Intrepid Explorer, Science, 6 July 2007
  16. ^ Parducci, L; Matetovici, I; Fontana, SL; Bennett, KD; Suyama, Y; Haile, J; Kjær, KH; Larsen, NK; Drouzas, AD; Willerslev, E (2013). "Molecular and pollen-based vegetation analysis in lake sediments from central Scandinavia". Mol. Ecol 22: 3511–3524. doi:10.1111/mec.12298. 
  17. ^ Willerslev, E.; Davison, J.; Moora, M.; Zobel, M.; Coissac, E.; Edwards, M. E.; Lorenzen, E. D.; Vestergård, M.; Gussarova, G.; Haile, J.; Craine, J.; Gielly, L.; Boessenkool, S.; Epp, L. S.; Pearman, P. B.; Cheddadi, R.; Murray, D.; Bråthen, K. A.; Yoccoz, N.; Binney, H.; Cruaud, C.; Wincker, P.; Goslar, T.; Alsos, I. G.; Bellemain, E.; Brysting, A. K.; Elven, R.; Sønstebø, J. R. H.; Murton, J.; et al. (2014). "Fifty thousand years of Arctic vegetation and megafaunal diet". Nature 506 (7486): 47–51. doi:10.1038/nature12921. PMID 24499916. 
  18. ^ Haile, J.; Froese, D. G.; MacPhee, R. D. E.; Roberts, R. G.; Arnold, L. J.; Reyes, A. V.; Rasmussen, M.; Nielsen, R.; Brook, B. W.; Robinson, S.; Demuro, M.; Gilbert, M. T. P.; Munch, K.; Austin, J. J.; Cooper, A.; Barnes, I.; Moller, P.; Willerslev, E. (2009). "Ancient DNA reveals late survival of mammoth and horse in interior Alaska". Proceedings of the National Academy of Sciences 106 (52): 22352–7. Bibcode:2009PNAS..10622352H. doi:10.1073/pnas.0912510106. PMC 2795395. PMID 20018740. 
  19. ^ Lorenzen, E. D.; Nogués-Bravo, D.; Orlando, L.; Weinstock, J.; Binladen, J.; Marske, K. A.; Ugan, A.; Borregaard, M. K.; Gilbert, M. T. P.; Nielsen, R.; Ho, S. Y. W.; Goebel, T.; Graf, K. E.; Byers, D.; Stenderup, J. T.; Rasmussen, M.; Campos, P. F.; Leonard, J. A.; Koepfli, K. P.; Froese, D.; Zazula, G.; Stafford, T. W.; Aaris-Sørensen, K.; Batra, P.; Haywood, A. M.; Singarayer, J. S.; Valdes, P. J.; Boeskorov, G.; Burns, J. A.; et al. (2011). "Species-specific responses of Late Quaternary megafauna to climate and humans". Nature 479 (7373): 359–64. Bibcode:2011Natur.479..359L. doi:10.1038/nature10574. PMID 22048313. 
  20. ^ Willerslev, E.; Davison, J.; Moora, M.; Zobel, M.; Coissac, E.; Edwards, M. E.; Lorenzen, E. D.; Vestergård, M.; Gussarova, G.; Haile, J.; Craine, J.; Gielly, L.; Boessenkool, S.; Epp, L. S.; Pearman, P. B.; Cheddadi, R.; Murray, D.; Bråthen, K. A.; Yoccoz, N.; Binney, H.; Cruaud, C.; Wincker, P.; Goslar, T.; Alsos, I. G.; Bellemain, E.; Brysting, A. K.; Elven, R.; Sønstebø, J. R. H.; Murton, J.; et al. (2014). "Fifty thousand years of Arctic vegetation and megafaunal diet". Nature 506 (7486): 47–51. Bibcode:2014Natur.506...47W. doi:10.1038/nature12921. PMID 24499916. 
  21. ^ Rasmussen, M; Li, Y; Lindgreen, S; Pedersen, JS; Albrechtsen, A; Moltke, I; Metspalu, M; Metspalu, E; Kivisild, T; Gupta, R; Bertalan, M; Nielsen, K; Gilbert, MTP; Wang, Y; Raghavan, M; Campos, PF; Kamp, HM; Wilson, AS; Gledhill, A; Tridico, S; Bunce, M; Lorenzen, ED; Binladen, J; Guo, X; Zhao, J; Zhang, X; Zhang, H; Li, Z; Chen, M; Orlando, L; Kristiansen, K; Bak, M; Tommerup, N; Bendixen, C; Pierre, TL; Grønnow, B; Meldgaard, M; Andreasen, C; Dedorova, SA; Osipova, LP; Higham, TFG; Bronk Ramsay, C; Hansen; Nielsen, FC; Crawford, MH; Brunak, S; Sicheritz-Pontén, T; Villems, R; Nielsen, R; Krogh, A; Wang, J; Willerslev, E (2010). "Ancient human genome sequence of an extinct Palaeo-Eskimo". Nature 463: 757–762. doi:10.1038/nature08835. PMC 3951495. PMID 20148029. 
  22. ^ "Recalibrating Equus evolution using the genome sequence of an early Middle Pleistocene horse.". Nature 499 (7456): 74–8. Jul 2013. doi:10.1038/nature12323. PMID 23803765. 
  23. ^ Raghavan, M.; Degiorgio, M.; Albrechtsen, A.; Moltke, I.; Skoglund, P.; Korneliussen, T. S.; Gronnow, B.; Appelt, M.; Gullov, H. C.; Friesen, T. M.; Fitzhugh, W.; Malmstrom, H.; Rasmussen, S.; Olsen, J.; Melchior, L.; Fuller, B. T.; Fahrni, S. M.; Stafford, T.; Grimes, V.; Renouf, M. A. P.; Cybulski, J.; Lynnerup, N.; Lahr, M. M.; Britton, K.; Knecht, R.; Arneborg, J.; Metspalu, M.; Cornejo, O. E.; Malaspinas; et al. (2014). "The genetic prehistory of the New World Arctic". Science 345 (6200): 1255832. doi:10.1126/science.1255832. PMID 25170159. 
  24. ^ Gilbert, M. T. P.; Jenkins, D. L.; Gotherstrom, A.; Naveran, N.; Sanchez, J. J.; Hofreiter, M.; Thomsen, P. F.; Binladen, J.; Higham, T. F. G.; Yohe, R. M.; Parr, R.; Cummings, L. S.; Willerslev, E. (2008). "DNA from Pre-Clovis Human Coprolites in Oregon, North America". Science 320 (5877): 786–9. Bibcode:2008Sci...320..786G. doi:10.1126/science.1154116. PMID 18388261. 
  25. ^ Raghavan, M.; Skoglund, P.; Graf, K. E.; Metspalu, M.; Albrechtsen, A.; Moltke, I.; Rasmussen, S.; Stafford Jr, T. W.; Orlando, L.; Metspalu, E.; Karmin, M.; Tambets, K.; Rootsi, S.; Mägi, R.; Campos, P. F.; Balanovska, E.; Balanovsky, O.; Khusnutdinova, E.; Litvinov, S.; Osipova, L. P.; Fedorova, S. A.; Voevoda, M. I.; Degiorgio, M.; Sicheritz-Ponten, T.; Brunak, S. R.; Demeshchenko, S.; Kivisild, T.; Villems, R.; Nielsen, R.; et al. (2013). "Upper Palaeolithic Siberian genome reveals dual ancestry of Native Americans". Nature 505 (7481): 87–91. Bibcode:2014Natur.505...87R. doi:10.1038/nature12736. PMC 4105016. PMID 24256729. 
  26. ^ Rasmussen, M.; Anzick, S. L.; Waters, M. R.; Skoglund, P.; DeGiorgio, M.; Stafford, T. W.; Rasmussen, S.; Moltke, I.; Albrechtsen, A.; Doyle, S. M.; Poznik, G. D.; Gudmundsdottir, V.; Yadav, R.; Malaspinas, A. S.; White, S. S.; Allentoft, M. E.; Cornejo, O. E.; Tambets, K.; Eriksson, A.; Heintzman, P. D.; Karmin, M.; Korneliussen, T. S.; Meltzer, D. J.; Pierre, T. L.; Stenderup, J.; Saag, L.; Warmuth, V. M.; Lopes, M. C.; Malhi, R. S.; Brunak, S. R.; Sicheritz-Ponten, T.; Barnes, I.; Collins, M.; Orlando, L.; Balloux, F.; Manica, A.; Gupta, R.; Metspalu, M.; Bustamante, C. D.; Jakobsson, M.; Nielsen, R.; Willerslev, E. (2014-02-13). "The genome of a Late Pleistocene human from a Clovis burial site in western Montana". Nature 506 (7487): 225–229. Bibcode:2014Natur.506..225R. doi:10.1038/nature13025. PMID 24522598. 
  27. ^ "For Crow-indianerne er han »Well-known Wolf«". www.b.dk. Retrieved 7 October 2014
  28. ^ Rasmussen, M; Sikora, M; Albrechtsen, A; Korneliussen, TS; Moreno-Mayar, JV; Poznik, GD; Zollikofer, CPE; Ponce; de León, MS; Allentoft, ME; Moltke, I; Jónsson, H; Valdiosera, C; Malhi, RS; Orlando, L; Bustamante, CD; Stafford Jr, T; Meltzer, DJ; Nielsen, R; Willerslev, Eske (2015). "The ancestry and affiliations of Kennewick Man". Nature. doi:10.1038/nature14625. 
  29. ^ Rasmussen, M; Guo, X; Wang, Y; Lohmueller, KE; Rasmussen, S; Albrechtsen, A; Skotte, L; Lindgreen, S; Metspalu, M; Jombart, T; Kivisild, T; Zhai, W; Eriksson, A; Manica, A; Orlando, L; De La, Vega F; Tridico, S; Metspalu, E; Nielsen, K; Ávila-Arcos, MC; Moreno-Mayar, JV; Muller, C; Dortch, J; Gilbert, MTP; Lund, O; Wesolowska, A; Karmin, M; Weiner, LA; Wang, B; Li, J; Tai, S; Xiao, F; Hanihara, T; van Driem, G; Jha, AR; Ricaut, F-X; de Knijff, P; Migliano, AB; Gallego-Romero, I; Kristiansen, K; Lambert, DM; Brunak, S; Forster, P; Brinkmann, B; Nehlich, O; Bunce, M; Richards, M; Gupta, R; Bustamante, C; Krogh, A; Foley, RA; Lahr, MM; Balloux, F; Sicheritz-Pontén, T; Villems, R; Nielsen, R; Jun, W; Willerslev, E (2012). "An Aboriginal Australian genome reveals separate human dispersals into Asia". Science 334: 94–98. doi:10.1126/science.1211177. 
  30. ^ Seguin-Orlando A, Korneliussen TS, Sikora M, Malaspinas AS, Manica A, Moltke I, Albrechtsen A, Ko A, Margaryan A, Moiseyev V, Goebel T, Westaway M, Lambert D, Khartanovich V, Wall JD, Nigst PR, Foley RA, Lahr MM, Nielsen R, Orlando L, and Willerslev E (2014) Genomic structure in Europeans dating back at least 36,200 years. Science. Nov 6. pii: aaa0114
  31. ^ Allentoft, ME; Sikora, M; Sjögren, K-G; Rasmussen, S; Rasmussen, M; Stenderup, J; Damgaard, PB; Schroeder, H; Ahlström, T; Vinner, L; Malaspinas, A-S; Margaryan, A; Higham, T; Chivall, D; Lynnerup, N; Harvig, L; Baron, J; Casa, PD; Dąbrowski, P; Duffy, PR; Ebel, AV; Epimakhov, A; Frei, K; Furmanek, M; Gralak, T; Gromov, A; Gronkiewicz, S; Grupe, G; Hajdu, T; Jarysz, R; Khartanovich, V; Khokhlov, A; Kiss, V; Kolář, J; Kriiska, A; Lasak, I; Longhi, C; McGlynn, G; Merkevicius, A; Merkyte, I; Metspalu, M; Mkrtchyan, R; Moiseyev, V; Paja, L; Pálfi, G; Pokutta, D; Pospieszny, L; Price, TD; Saag, L; Sablin, M; Shishlina, N; Smrčka, VC; Soenov, VI; Szeverényi, V; Tóth, G; Trifanova, SV; Varul, L; Vicze, M; Yepiskoposyan, L; Zhitenev, V; Orlando, L; Sicheritz-Pontén, T; Brunak, S; Nielsen, R; Kristiansen, K; Willerslev, Eske (2015). "Population genomics of Bronze Age Eurasia". Nature 522: 167–172. doi:10.1038/nature14507. 
  32. ^ Rasmussen; et al. (2015). "Early divergent strains of Yersinia pestis in Eurasia 5,000 years ago". Cell 163: 571–582. doi:10.1016/j.cell.2015.10.009. 
  33. ^ Overballe-Petersen, S.; Harms, K.; Orlando, L. A. A.; Mayar, J. V. M.; Rasmussen, S.; Dahl, T. W.; Rosing, M. T.; Poole, A. M.; Sicheritz-Ponten, T.; Brunak, S.; Inselmann, S.; De Vries, J.; Wackernagel, W.; Pybus, O. G.; Nielsen, R.; Johnsen, P. J.; Nielsen, K. M.; Willerslev, E. (2013). "Bacterial natural transformation by highly fragmented and damaged DNA". Proceedings of the National Academy of Sciences 110 (49): 19860–5. Bibcode:2013PNAS..11019860O. doi:10.1073/pnas.1315278110. PMID 24248361. 
  34. ^ Johnson, SS; Hebsgaard, MB; Christensen, T; Mastepanov, M; Nielsen, R; Munch, K; Brand, TB. Gilbert MTP; Zuber, MT; Bunce, M; Rønn, R; Gilichinsky, D; Froese, D; Willerslev, E. (2007). "Ancient bacteria show evidence of DNA repair". Proc. Natl. Acad. Sci. USA 104: 14401–14405. 
  35. ^ Orlando, L.; Ginolhac, A. L.; Zhang, G.; Froese, D.; Albrechtsen, A.; Stiller, M.; Schubert, M.; Cappellini, E.; Petersen, B.; Moltke, I.; Johnson, P. L. F.; Fumagalli, M.; Vilstrup, J. T.; Raghavan, M.; Korneliussen, T.; Malaspinas, A. S.; Vogt, J.; Szklarczyk, D.; Kelstrup, C. D.; Vinther, J.; Dolocan, A.; Stenderup, J.; Velazquez, A. M. V.; Cahill, J.; Rasmussen, M.; Wang, X.; Min, J.; Zazula, G. D.; Seguin-Orlando, A.; Mortensen, C. (2013). "Recalibrating Equus evolution using the genome sequence of an early Middle Pleistocene horse". Nature 499 (7456): 74–78. Bibcode:2013Natur.499...74O. doi:10.1038/nature12323. PMID 23803765. 

External links[edit]