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◥ differ from those of Wailekia and Kyitchaungia RESEARCH ARTICLES in having lingually open trigonids with proto- conid and metaconid more closely approximated and talonids bearing more trenchant cristids. PRIMATE EVOLUTION UppermolarsdifferfromthoseofGuangxilemur in having more prominent parastyles and pre- and postprotocristae joining the bases of the Oligocene primates from China reveal paracone and metacone, respectively, rather than merging with the pre- and postcingula. Upper molars with weaker buccal cingulum and incom- divergence between African and plete mesostyle, in contrast to Guangxilemur tongi. Lower molars differ from those of Guang- Asian primate evolution xilemur singsilai in having lingually open trig- onids and deeper, more extensive valley separating Xijun Ni,1,2* Qiang Li,1,2 Lüzhou Li,1 K. Christopher Beard3,4 entoconid and hypoconulid. Differs from Miocene 4 sivaladapids in lacking fully molariform P4 and P Profound environmental and faunal changes are associated with climatic deterioration and having upper molars with distinct pericone during the Eocene-Oligocene transition (EOT) roughly 34 million years ago. Reconstructing and hypocone cusps and pre- and postprotocris- how Asian primates responded to the EOT has been hindered by a sparse record of tae joining bases of paracone and metacone. Oligocene primates on that continent. Here, we report the discovery of a diverse primate Etymology: Generic name recognizes the geo- fauna from the early Oligocene of southern China. In marked contrast to Afro-Arabian graphic provenance of this taxon and its adapi- Downloaded from Oligocene primate faunas, this Asian fauna is dominated by strepsirhines. There appears to form affinities. be a strong break between Paleogene and Neogene Asian anthropoid assemblages. Asian Yunnanadapis folivorus sp. nov. Holotype: and Afro-Arabian primate faunas responded differently to EOT climatic deterioration, IVPP V22702, left dentary fragment preserving indicating that the EOT functioned as a critical evolutionary filter constraining the the crowns of C1-M3 (Fig. 1A and supplementary subsequent course of primate evolution across the Old World. materials). Horizon and locality:EarlyOligo- cene Lijiawa fossil site, upper part of Caijiachong Formation, Yuezhou Basin, Yunnan Province, China. http://science.sciencemag.org/ rimates are among the most thermophilic primates has been hindered by geographic and Diagnosis: Smaller than Yunnanadapis impera- and hence environmentally sensitive of all temporal biases in the Asian fossil record. Eocene tor.P3 without buccal cingulid, in contrast to Y. mammals. As a result, both the geographic primates have been sporadically reported from imperator.P4 differs from that of Y. imperator in P distribution and macroevolutionary pat- northern China and Mongolia (10–12), but Eocene having much weaker buccal cingulid and hypo- terns shown by fossil primates are strongly primatesaremorediverseandabundantinsouth- conidandcristidobliquamorelingualinposition, mediated by shifting climatic conditions during ern Asia, where the Oligocene record is generally yielding deeper hypoflexid and narrower talonid the Cenozoic. Dramatic range expansions, such absent (13, 14). With the sole exception of the late basin. Etymology: Trivial name reflects the likely as the dispersal of the earliest primates from early Oligocene Paali Nala locality in the Bugti dietary adaptations of this species. their Asian birthplace into North America and Hills of Pakistan (15–17), Oligocene primates are Yunnanadapis imperator sp. nov. Holotype: Europe during the Paleocene-Eocene Thermal unknown in Asia. This very limited record of IVPP V22706, right P (Fig. 1B and supplemen-
4 Maximum, coincided with intervals of extreme Asian Oligocene primates has made it difficult to tary materials). Horizon and locality:Early on October 25, 2017 global warmth (1, 2). In contrast, episodes of assess the impact of EOT environmental changes Oligocene Lijiawa fossil site, upper part of Cai- cooler, drier climatic conditions such as that on Asian primate evolution. Here, we describe a jiachong Formation, Yuezhou Basin, Yunnan characterizing the Eocene-Oligocene transition diverseassemblageoffossilprimatesfromthe Province, China. Diagnosis:LargerthanYun- (EOT) resulted in continental-scale extinction of early Oligocene of Yunnan Province in southern nanadapis folivorus.P3 with strong buccal cin- primates on landmasses that lacked direct geo- China that helps to fill this gap in the record of gulid, in contrast to Y. folivorus.P4 differs from graphic access to low-latitude refugia (3). Pri- Asian primate evolution. that of Y. folivorus in having much stronger mates were extirpated at or near the EOT in North We collected the primate fossils reported here buccal cingulid and hypoconid and cristid obli- America and Europe, but Afro-Arabian primate via careful excavation and screen-washing at the qua more buccal in position, yielding shallower faunas dominated by anthropoids continued to Lijiawa fossil site in Yunnan, which has yielded hypoflexid and wider talonid basin. Etymology: radiateduringtheOligoceneandNeogene(4–7). more than 10 mammal taxa that indicate an early Latin “imperator” (commander), in allusion to In northern China and Mongolia, mammalian Oligocene age (supplementary materials) (18). the large size of this species. faunal turnover across the EOT was pervasive Primates Linnaeus, 1758; Strepsirhini Geoffroy, Laomaki yunnanensis gen. et sp. nov. Holo- enough to be compared with the European Grande 1812; Adapiformes Hoffstetter, 1977; Sivaladapi- type:IVPPV22708,rightmaxillafragmentpre- Coupure, and this abrupt change in Asian mam- dae Thomas and Verma, 1979; Yunnanadapis serving M1-3 (Fig. 1C and supplementary materials). mal faunas has been designated the Mongolian gen. nov. Type species: Yunnanadapis folivorus Horizon and locality: Early Oligocene Lijiawa Remodeling (8, 9). However, assessing the im- sp. nov. Included species:Thetypespeciesand fossil site, upper part of Caijiachong Formation, pact of EOT climatic deterioration on early Asian Yunnanadapis imperator sp. nov. Diagnosis: Yuezhou Basin, Yunnan Province, China. Diag- Differs from Paukkaungia, Hoanghonius,and nosis: Differs from all sivaladapids aside from Rencunius in having more nearly molariform P4 Rencunius in having strongly developed conules 1 4 4 4 Key Laboratory of Vertebrate Evolution and Human Origins, and P (P remains unknown in Paukkaungia). on upper molars. P4 and P lack substantial mo- Institute of Vertebrate Paleontology and Paleoanthropology Lower molars further differ from those of Pauk- larization, in contrast to Yunnanadapis and Mio- (IVPP), Chinese Academy of Sciences, 142 Xi Zhi Men Wai kaungia, Hoanghonius,andRencunius in having cene sivaladapids. Upper and lower molars differ Street, Beijing, 100044, China. 2Chinese Academy of Sciences (CAS) Center for Excellence in Tibetan Plateau less cuspidate paraconids and more angular hy- from those of Rencunius and Paukkaungia in Earth Sciences, Beijing, 100101, China. 3Biodiversity Institute, poconids that are relatively mesial in position, having highly crenulated enamel, taller and more University of Kansas, 1345 Jayhawk Boulevard, Lawrence, KS so that the cristid obliqua is shorter than the pyramidal cusps/cuspids, and more trenchant 4 66045-7561, USA. Department of Ecology and Evolutionary postcristid. Upper molars further differ from crests/cristids. Upper molars are more transverse Biology, University of Kansas, 1345 Jayhawk Boulevard, Lawrence, KS 66045-7561, USA. those of Hoanghonius and (especially) Rencu- than those of Rencunius, and upper molar con- 4 *Corresponding author. Email: [email protected] nius in lacking distinct conules. Lower molars ules are pyramidal rather than bulbous. P bears
SCIENCE sciencemag.org 6MAY2016• VOL 352 ISSUE 6286 673 RESEARCH | RESEARCH ARTICLES a tiny hypocone, in contrast to that of Rencunius. to those of Bugtilemur and Muangthanhinius,in from Eocene Tarsius eocaenus and modern Tar- Etymology: Generic name derives from the which these structures are obliquely oriented so sius pumilus. Differs from extant tarsiids and Mandarin “lao” (old) and the Malagasy “maky” that metaconid is located distolingual to proto- Miocene Hesperotarsius in having well-developed (lemur). Trivial name reflects the geographic prov- conid. Upper molars differ from those of Bugtilemur conules and distobuccally oriented postmetacrista enance of this species. in having more inflated (rather than buccolingually on M1. Postprotocrista of M1 continuous with Ekgmowechashalidae Szalay, 1976; Gatanthro- compressed) paracone and metacone, broader postmetaconule crista, rather than merging with pus micros gen. et sp. nov. Holotype: IVPP V22717, buccal cingulum, and stronger and more exten- hypometacrista to form distal margin of trigon, as isolated left M1 (Fig. 1D and supplementary sive postprotocingulum. Etymology: In allusion in extant tarsiids. M1 differs from that of Eocene materials). Horizon and locality:EarlyOligo- to the ekgmowechashalid affinities of this taxon, Xanthorhysis in being relatively shorter, broader, cene Lijiawa fossil site, upper part of Caijiachong its generic name derives from the Greek “gata” and higher-crowned, with entoconid located far- Formation, Yuezhou Basin, Yunnan Province, (cat) and “anthropus” (man), and its trivial name ther mesially. Lacks hypoparacrista and hypome- China. Diagnosis: Differs from other ekgmowe- derives from the Greek “micros” (small). Ekgmo- tacrista. Etymology: Generic name reflects the chashalid primate genera (including Bugtilemur, wechashala signifies “little cat man” in the Lakota age of this taxon. Trivial name reflects the sparse Muangthanhinius,andEkgmowechashala)inhav- language, which lacks a term for nonhuman documentation of Tarsiidae in the fossil record ing simpler, more nearly premolariform P4 with primates. generally, as well as the meager representation of hypconid and cristid obliqua located near the Haplorhini Pocock, 1918; Tarsiiformes Gregory, this species in the Caijiachong early Oligocene midline of the talonid, rather than buccally as in 1915; Tarsiidae Gray, 1825; Oligotarsius rarus gen. fauna. Bugtilemur and Muangthanhinius.P4 without et sp. nov. Holotype: IVPP V22727, isolated left Anthropoidea Mivart, 1864; Eosimiidae Beard neomorphic buccal cingular cuspid, in contrast M1 (Fig. 1E and supplementary materials). Hori- et al., 1994; Bahinia Jaeger et al., 1999; Bahinia to Ekgmowechashala.M1-2 lack prominent devel- zon and locality: Early Oligocene Lijiawa fossil banyueae sp. nov. Holotype: IVPP V22730, iso- 1 opment of metastylids, in contrast to Ekgmowe- site, upper part of Caijiachong Formation, Yuez- lated right M (Fig. 1F and supplementary ma- Downloaded from chashala. Protoconid, protocristid, and metaconid hou Basin, Yunnan Province, China. Diagnosis: terials, comments regarding possible additional of lower molar are transversely aligned, in contrast Smaller than other living and fossil tarsiers, aside elements pertaining to the holotype). Horizon http://science.sciencemag.org/
on October 25, 2017
Fig. 1. Diverse primates from the early Oligocene of Yunnan Province, China. V22720, and V22721, respectively); left M1 (holotype, IVPP V22717); left M2 1 2 3 (A) Yunnanadapis folivorus gen. et sp. nov., left dentary fragment preserving C1-M3 and M3 (IVPP V22722 and V22723, respectively); right M ,M,andM (IVPP (holotype, IVPP V22702), and composite upper dentition including right dP4 (IVPP V22724, V22725, and V22726, respectively). (E) Oligotarsius rarus gen. et sp. V22703), reversed left P4 (IVPP V22704), and right maxillary fragment preserving nov., reversed left C1 and M1 (IVPP V22728 and V22729, respectively), and left 1-3 2 M (IVPP V22705). (B) Yunnanadapis imperator gen. et sp. nov., left P3 (IVPP M1 (holotype, IVPP V22727). (F) Bahinia banyueae sp. nov., reversed left P 3 4 V22707), and reversed right P4 (holotype, IVPP V22706). (C) Laomaki yunnanensis and P (IVPP V22731 and V22732, respectively), right P (IVPP V22733), right gen. et sp. nov., right maxillary fragment preserving M1-3 (holotype, IVPP V22708); M1 (holotype, IVPP V22730), right M2 missing metacone lobe (IVPP V22734) reversed left P3,P4,andM1 (IVPP V22714, V22715, and V22716, respectively); reversed juxtaposed with a right M2 fragment preserving metacone lobe only (IVPP 3 right dentary fragment preserving P3,P4,M1,M2,andM3 (IVPP V22709, V22735), right M (IVPP V22736), left P3 and left trigonid of M1 (IVPP V22737
V22710, V22711, V22712, and V22713, respectively). (D) Gatanthropus micros and V22738, respectively), reversed right M2 trigonid and talonid (IVPP gen. et sp. nov., left C1 (IVPP V22718); reversed right P2,P3,P4 (IVPP V22719, V22739 and V22740, respectively). Scale bars, 2 mm.
674 6MAY2016• VOL 352 ISSUE 6286 sciencemag.org SCIENCE RESEARCH | RESEARCH ARTICLES and locality: Early Oligocene Lijiawa fossil site, in traversing the EOT were able to persist there from Pakistan differ from their contemporary upper part of Caijiachong Formation, Yuezhou for tens of millions of years, showing that the African relatives in being relatively small-bodied. Basin, Yunnan Province, China. Diagnosis:Up- EOT functioned as a critical filtering episode Phylogenetic analysis (Fig. 3) shows that Yunna- permolarswithweakerbuccalandlingual during the evolutionary history of Asian primates. nadapis folivorus, Y. imperator,andLaomaki cingula than in Bahinia pondaungensis.Although Comparing the composition of the early Oligocene yunnanensis belong to the Sivaladapidae, a clade P2
32 2 on October 25, 2017 33 34 EOB 35 36 37 38 39 1 40 Karanisia clarki Tarsiiform Biretia piveteaui Serapia eocaena Karanisia arenula Arsinoea kallimos Afrotarsius libycus Biretia fayumensis Biretia megalopsis Aframonius dieides Wadilemur elegans Krabia minuta Plesiopithecus teras Afrasia djijidae Catopithecus browni Talahpithecus parvus Qatrania basiodontos " Anchomomys milleri Proteopithecus sylviae Nosmips aenigmaticus Gatanthropus sp. Afradapis longicristatus Wailekia orientale Saharagalago misrensis Pondaungia cotteri Paukkaungia parva Laomaki yunnanensis Kyitchaungia takaii Pondaungia minuta Guangxilemur tongi Ganlea megacanina Muangthanhinius siami Bahinia pondaungensis Siamopithecus eocaenus Myanmarpithecus yarshensis
Afro-Arabian strepsirhines Afro-Arabian haplorhines Asian haplorhines Asian strepsirhines Fig. 2. Divergent taxonomic composition of fossil primates across the persist to later intervals. Dashed line with arrowhead 1 indicates interconti- Eocene-Oligocene boundary (EOB) in Afro-Arabia and southern Asia. Gray nental dispersal of early anthropoids from Asia to Afro-Arabia (6, 27). Dashed area indicates haplorhines. Pale red area indicates strepsirhines. The phylo- line with arrowhead 2 indicates a second dispersal episode of anthropoids genetic affinities of Nosmips are uncertain (26).Thewidthoftheshadedareas between Afro-Arabia and Asia during the early Oligocene, as suggested by our directly reflects taxonomic diversity. Solid red and gray lines designate gen- phylogenetic analysis that Phileosimias and Bugtipithecus aremoreclosely erally accepted monophyletic groups (Fig. 3) (6). Dashed lines indicate hy- related to Afro-Arabian anthropoids than to Asian anthropoids (supplementary pothetical range extensions in earlier strata.White arrows indicate that lineages materials). Ma, million years ago.
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favored strepsirhines over haplorhines. Ecologi- Outgroup Fig. 3. Summary phylo- cally, strepsirhines were the only Asian primates geny of 196 mammals. to occupy those niches available to primates of 13 tree shrews Parsimony analysis is relatively large body mass because medium and based on a data matrix large haplorhine taxa such as amphipithecids 29 plesiadapiforms that includes 1227 mor- and flying lemurs were eradicated across the EOT in Asia. This phological characters pattern of turnover across the EOT among and 663 molecular Asian primates differs radically from that 15 lemuriforms characters of long and which has been observed in Afro-Arabia. There, Protoadapis curvicuspidens short interspersed only small strepsirhines survived the EOT, whereas Rencunius spp. Sivaladapids nuclear elements scored Laomaki yunnanensis anthropoid haplorhines diversified to occupy a Hoanghonius stehlini for 149 fossil and 47 54 strepsirhines range of body sizes that was nearly an order of Paukkaungia parva living taxa. The topology Yunnanadapis spp. magnitude larger than their previous distribu- Guangxilemur spp. of extant treeshrews, Sinoadapis shihuibaensis tion (Fig. 4). The divergent responses shown by Sivaladapis nagrii flying lemurs, and pri- -chashalids Afro-Arabian and Asian primates across the EOT Periconodon pygmaeus Ekgmowe mates used as a Ekgmowechashala philotau set the stage for subsequent macroevolutionary Gatanthropus micros backbone constraint or patterns within this group. Africa became the Bugtilemur mathesoni “molecular scaffold” is Muangthanhinius siami geographic nexus of anthropoid evolution, whereas based on a gene super- Asia continued to harbor sivaladapid strepsirhines matrix (supplementary 25 adapids and tarsiid haplorhines. Dynamic changes to materials). the Asian physical environment during the in- Downloaded from terval spanning the EOT included progressive retreat of the Paratethys Sea from central Asia, Pseudoloris parvulus
Vectipithex raabi 44 tarsiiforms continued uplift of the Tibetan-Himalayan orogen, Microchoerus erinaceus Necrolemur spp. and opening of the South China Sea (24). Africa Altanius orlovi was not immune to global climatic changes Afrasia djijidae
Afrotarsius chatrathi 98 haplorhines across the EOT, but it did not experience the Afrotarsius libycus Tarsiids Xanthorhysis tabrumi http://science.sciencemag.org/ dramatic tectonic and paleogeographic alter- Oligotarsius rarus ations that characterized Asia at this time. It is Tarsius syrichta Eosimiids tempting to attribute the different patterns of Phenacopithecus spp. anthropoids
Bahinia banyueae 20 stem turnover in Asian and African primate faunas Bahinia pondaungensis Eosimias centennicus across the EOT to local changes in vegetation Eosimias sinensis and paleoenvironment (25), but current evi- Eosimiid Nyaungpinle dence is not sufficient to rule out the possibility that stochastic processes also played a substan- 34 crown anthropoids tial role.
g EOB
Fig. 4. Body-mass spectrum of fossil primates on October 25, 2017 6000 across the EOB in Afro-Arabia and southern Afro-Arabian late Eocene primates Afro-Arabian early Oligocene primates Asia. Gray bars represent haplorhines. Pale red bars 4000 represent strepsirhines. Nosmips is uncertain (26). Later Eocene Afro-Arabian anthropoids occupy the 2000 middle of the spectrum. Later Eocene Afro-Arabian strepsirhines dominate the two extremes. Early 0 Oligocene Afro-Arabian strepsirhines are restricted to the small end of the body-size distribution. Early Oligocene Afro-Arabian anthropoids span most of the body-mass range. Later Eocene Asian strep- Qatrania wingi Apidium bowni Karanisia clarki Apidium zuetina Biretia piveteaui Qatrania fleaglei sirhines occupy the middle part of the body-mass Serapia eocaena Karanisia arenula Omanodon minor Arsinoea kallimos Afrotarsius libycus Biretia fayumensis Biretia megalopsis Apidium moustafai Aframonius dieides Wadilemur elegans Wadilemur Simonsius grangeri Parapithecus fraasi Apidium phiomense Afrotarsius chatrathi Oligopithecus rogeri Plesiopithecus teras spectrum. Later Eocene Asian anthropoids dominate Catopithecus browni Talahpithecus parvus Talahpithecus Qatrania basiodontos " Anchomomys milleri Propliopithecus ankeli Oligopithecus savagei Proteopithecus sylviae Nosmips aenigmaticus Afradapis longicristatus Aegyptopithecus zeuxis Shizarodon dhofarensis Moeripithecus markgrafi Saharagalago misrensis the small and large body-mass areas. Early Oligo- Propliopithecus haeckeli Unidentified oligopithecid cene Asian anthropoids are restricted to the small g Propliopithecus chirobates 6000 body-mass area. Early Oligocene Asian strepsirhines Moeripithecus markgrafi Taqah continue to occupy a broad range of body masses. Asian late Eocene primates Asian early Oligocene primates Data are listed in table S2. 4000
2000
0 Tarsiiform Krabia minuta Afrasia djijidae Gatanthropus sp. Wailekia orientale Oligotarsius rarus Bahinia banyueae Pondaungia cotteri Paukkaungia parva Kyitchaungia takaii Pondaungia minuta Phileosimias kamali Guangxilemur tongi Ganlea megacanina Gatanthropus micros Bugtilemur mathesoni Laomaki yunnanensis Guangxilemur singsilai Muangthanhinius siami Bahinia pondaungensis Yunnanadapis folivorus Phileosimias brahuiorum Yunnanadapis imperator Siamopithecus eocaenus Bugtipithecus inexpectans Myanmarpithecus yarshensis
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ASTROPARTICLE PHYSICS interstellar medium (ISM) by the spectrometer on the International Gamma-Ray Astrophysics 60 Laboratory (INTEGRAL) spacecraft have revealed Observation of the Fe line emission at 1173 and 1333 keV from 60Co, the daughter product of 60Fe decay, clear evidence nucleosynthesis-clock isotope in that “nucleosynthesis is ongoing in the galaxy” http://science.sciencemag.org/ (6). As expected, this emission is diffuse instead of point-like, since the 60Fe lifetime is sufficiently galactic cosmic rays long to allow it to diffuse over distances that are W. R. Binns,1* M. H. Israel,1* E. R. Christian,2 A. C. Cummings,3 G. A. de Nolfo,2 large compared to the size of a supernova rem- K. A. Lave,1 R. A. Leske,3 R. A. Mewaldt,3 E. C. Stone,3 nant. This is one of many strong connections between g-ray astronomy and direct cosmic-ray T. T. von Rosenvinge,2 M. E. Wiedenbeck4 studies (7). Deep-sea manganese crusts from two differ- Iron-60 (60Fe) is a radioactive isotope in cosmic rays that serves as a clock to infer an upper ent locations have also been found to harbor limit on the time between nucleosynthesis and acceleration. We have used the ACE-CRIS 60 5 elevated Fe levels (8, 9). Analysis of crust layers – instrument to collect 3.55 × 10 iron nuclei, with energies ~195 to ~500 mega electron volts per on October 25, 2017 − using accelerator mass spectrometry showed nucleon, of which we identify 15 60Fe nuclei. The 60Fe/56Fe source ratio is (7.5 ± 2.9) × 10 5. significant increases in the 60Fe/Fe ratio 2.8 The detection of supernova-produced 60Fe in cosmic rays implies that the time required for million years (My) ago, “compatible with depo- acceleration and transport to Earth does not greatly exceed the 60Fe half-life of 2.6 million years sition of supernova ejecta at a distance of a few and that the 60Fe source distance does not greatly exceed the distance cosmic rays can diffuse tens of pc” (9). The measurement was verified over this time, ⪍1 kiloparsec. A natural place for 60Fe origin is in nearby clusters of massive stars. by an independent analysis (10), although these investigators did not find a corresponding in- ignature of recent nucleosynthesis exception of 59Ni, for which only an upper limit crease in a marine-sediment sample [see (10, 11) The radioactive isotope 60Fe [which decays by is available (2)] produced with a half-life long for discussion]. We note that the manganese b– decaywithahalf-lifeof2.62×106 years (1)] enough to potentially survive the time interval crust studies (8–10) used outdated half-lives for S is expected to be synthesized and ejected into between nucleosynthesis and detection at Earth. 60Fe and 10Be—1.49 and 1.51 My , respectively— space by supernovae, and thus could be (Primary cosmic rays are those that are synthe- instead of the currently accepted 2.62 and 1.387 My present in galactic cosmic rays (GCRs) near Earth, sized at the GCR source, as opposed to secondary (1). Using these recent lifetimes, it has been esti- depending upon the time elapsed since nucleo- cosmic rays, which are produced by nuclear in- mated that the peak in the 60Fe/Fe ratio (9)asa synthesis and the distance of the supernovae. teractions in the interstellar medium.) 60Fe is dif- function of depth corresponds to an age of 2.2 My 60Fe is believed to be produced primarily in ficult to measure with present-day instruments (11). Lunar surface samples also show elevated core-collapse supernovae of massive stars with because of its expected extreme rarity, based on 60Fe/Feratiosconsistentwithsupernovadebris mass M > ~10 solar masses (M⊙), which occur nucleosynthesis calculations for supernovae arriving on the Moon ~2 My ago (12, 13). These mostly in associations of massive stars (OB (3, 4). The detection of 60Fe in cosmic rays would deep-sea manganese crust and lunar surface associations). It is the only primary radioactive be a clear sign of recent, nearby nucleosynthe- observations were compared with expectations isotope with atomic number Z ≤ 30 [with the sis. The long period of data collection (17 years) from possible stellar sources (11) and found to achieved by the Cosmic Ray Isotope Spectrometer be consistent with an origin in core-collapse (CRIS) aboard NASA’s Advanced Composition supernovae, but inconsistent with Type Ia su- 1Washington University, St. Louis, MO 63130, USA. Explorer (ACE) (5), the excellent mass and charge pernovae, which produce orders of magnitude 60 2NASA/Goddard Space Flight Center, Greenbelt, MD 20771, resolution of the CRIS instrument, and its capa- less Fe. USA. 3California Institute of Technology, Pasadena, CA bility for background rejection have enabled us 4 60 91125, USA. Jet Propulsion Laboratory, California Institute to detect 60Fe. Cosmic-ray Fe detection of Technology, Pasadena, CA 91109, USA. 60 *Corresponding author: Email: [email protected] (W.R.B.); Fe has been detected in other samples of The CRIS instrument was launched on ACE in [email protected] (M.H.I.) matter. Measurements of diffuse g-rays from the 1997 and has operated continuously since that
SCIENCE sciencemag.org 6MAY2016• VOL 352 ISSUE 6286 677 Oligocene primates from China reveal divergence between African and Asian primate evolution Xijun Ni, Qiang Li, Lüzhou Li and K. Christopher Beard
Science 352 (6286), 673-677. DOI: 10.1126/science.aaf2107
Climate filters dominant species The transition between the Eocene and Oligocene periods was marked by distinct cooling. Because primate species are particularly susceptible to cold, this change in climate drove a retraction of primates globally. After this transition, anthropoid primates were dominant in Afro-Arabian regions, but little has been known about primate Downloaded from reestablishment in Asia. Ni et al. describe 10 previously unknown primates found in Yunnan Province in China that show that primates took a different path in Asia. Instead of anthropoids, strepsirrhine (lemur-like) primates were dominant. It is still unknown whether this difference was due to the environment or chance. Science, this issue p. 673 http://science.sciencemag.org/
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