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A quantum computer attains computational advantage when outperforming the best classical computers running the best-known algorithms on well-defined tasks. No photonic machine offering programmability over all its quantum gates has demonstrated quantum computational advantage: previous machines1,2 were largely restricted to static gate sequences. Earlier photonic demonstrations were also vulnerable to spoofing3, in which classical heuristics produce samples, without direct simulation, lying closer to the ideal distribution than do samples from the quantum hardware. Here we report quantum computational advantage using Borealis, a photonic processor offering dynamic programmability on all gates implemented. We carry out Gaussian boson sampling4 (GBS) on 216 squeezed modes entangled with three-dimensional connectivity5, using a time-multiplexed and photon-number-resolving architecture. On average, it would take more than 9,000 years for the best available algorithms and supercomputers to produce, using exact methods, a single sample from the programmed distribution, whereas Borealis requires only 36 μs. This runtime advantage is over 50 million times as extreme as that reported from earlier photonic machines. Ours constitutes a very large GBS experiment, registering events with up to 219 photons and a mean photon number of 125. This work is a critical milestone on the path to a practical quantum computer, validating key technological features of photonics as a platform for this goal.

Growing interest in quantum computing for practical applications has led to a surge in the availability of programmable machines for executing quantum algorithms1,2. Present-day photonic quantum computers3–7 have been limited either to non-deterministic operation, low photon numbers and rates, or fixed random gate sequences. Here we introduce a full-stack hardware−software system for executing many-photon quantum circuit operations using integrated nanophotonics: a programmable chip, operating at room temperature and interfaced with a fully automated control system. The system enables remote users to execute quantum algorithms that require up to eight modes of strongly squeezed vacuum initialized as two-mode squeezed states in single temporal modes, a fully general and programmable four-mode interferometer, and photon number-resolving readout on all outputs. Detection of multi-photon events with photon numbers and rates exceeding any previous programmable quantum optical demonstration is made possible by strong squeezing and high sampling rates. We verify the non-classicality of the device output, and use the platform to carry out proof-of-principle demonstrations of three quantum algorithms: Gaussian boson sampling, molecular vibronic spectra and graph similarity8. These demonstrations validate the platform as a launchpad for scaling photonic technologies for quantum information processing. A system for realizing many-photon quantum circuits is presented, comprising a programmable nanophotonic chip operating at room temperature, interfaced with a fully automated control system.

Dire wolves are considered to be one of the most common and widespread large carnivores in Pleistocene America1, yet relatively little is known about their evolution or extinction. Here, to reconstruct the evolutionary history of dire wolves, we sequenced five genomes from sub-fossil remains dating from 13,000 to more than 50,000 years ago. Our results indicate that although they were similar morphologically to the extant grey wolf, dire wolves were a highly divergent lineage that split from living canids around 5.7 million years ago. In contrast to numerous examples of hybridization across Canidae2,3, there is no evidence for gene flow between dire wolves and either North American grey wolves or coyotes. This suggests that dire wolves evolved in isolation from the Pleistocene ancestors of these species. Our results also support an early New World origin of dire wolves, while the ancestors of grey wolves, coyotes and dholes evolved in Eurasia and colonized North America only relatively recently. © 2021, The Author(s), under exclusive licence to Springer Nature Limited. Acknowledgements We thank the staff at the Carnegie Museum of Natural History, Cincinnati Museum Center, Danish Zoological Museum, Harrison Zoological Museum, Harvard Museum of Comparative Zoology, Idaho Museum of Natural History, Institute of Archaeology (Russian Academy of Sciences), Institute of Systematics and Animal Ecology (Russian Academy of Sciences), Institute of Zoology (Chinese Academy of Sciences), Instituto de Conservação da Natureza e das Florestas, Kansas Museum of Natural History, La Brea Tar Pits and Museum, Ludwig Maximilian University, McClung Museum, Museum of the Institute of Plant and Animal Ecology (Russian Academy of Sciences), Museum national d’Histoire naturelle, National Museums Scotland, Natural History Museum London, Naturalis Biodiversity Center, Naturhistorisches Museum Bern, Smithsonian National Museum of Natural History, Swedish Naturhistoriska Riksmuseet, SYLVATROP, US Bureau of Reclamation, University of California Museum of Paleontology, University of Texas at El Paso, University of Washington Burke Museum and the Zoological Institute (Russian Academy of Sciences; state assignment no. АААА-А19-119032590102-7) for access to specimens in their care; T. Barnosky, S. Bray, A. Farrell, R. Fischer, A. Harris, J. Harris, A. Henrici, P. Holroyd, R. MacPhee, T. Martin, A. Philpot, J. Saunders, J. Southon, G. Storrs, G. Takeuchi, X. Wang and C. Widga for assistance; and L. DeSantis for comments. A.M. used computational and storage services associated with the Hoffman2 Shared Cluster provided by UCLA Institute for Digital Research and Education’s Research Technology Group. DireGWC was sequenced using the Vincent J. Coates Genomics Sequencing Laboratory at UC Berkeley, supported by NIH S10 OD018174 Instrumentation Grant. We acknowledge the assistance of the Danish National High-Throughput Sequencing Centre, BGI-Europe, the Garvan Institute of Medical Research and the Australian Cancer Research Foundation (ACRF) Cancer Genomics Facility for assistance in Illumina and BGIseq500 data generation. A.R.P. was supported by a Marie Curie COFUND Junior Research Fellowship (Durham University). A.M. was supported by an NSF grant (award number: 1457106) and the QCB Collaboratory Postdoctoral Fellowship (UCLA). L.A.F.F., J.H., A.H.-B. and G.L. were supported by either European Research Council grant (ERC-2013-StG-337574-UNDEAD and ERC-2019-StG-853272-PALAEOFARM) and/or Natural Environmental Research Council grants (NE/K005243/1 and NE/K003259/1). K.S. was supported by a grant from Barrett, the Honors College at Arizona State University. A.T.O. was supported by the Strategic Initiative Funds, Office of the President, Arizona State University to the Institute of Human Origins DNA and Human Origins at Arizona State University project. L.A.F.F. was supported by a Junior Research Fellowship (Wolfson College, University of Oxford) and L.A.F.F. and A. Carmagnini were supported by the Wellcome Trust (210119/Z/18/Z). S.G. was supported by Carlsbergfondet grant CF14–0995 and Marie Skłodowska-Curie Actions grant 655732-WhereWolf. M.T.P.G. was supported by ERC Consolidator grant 681396-Extinction Genomics. B.S. and J.K. were supported by IMLS MG-30-17-0045-17 and NSF DEB-1754451. A.H.-B. was supported by the Leverhulme Trust (ECF-2017-315). A. Cooper, K.J.M. and H.H. were supported by the Australian Research Council. A.T.S. and G.G. were supported by Australian Government Research Training Program Scholarships. A.T.L. was supported by the Peter Buck Postdoctoral Fellowship from the Smithsonian Institution’s National Museum of Natural History. Y.V.K. was supported by the by State Assignment of the Sobolev Institute of Geology and Mineralogy.

Clovis, with its distinctive biface, blade and osseous technologies, is the oldest widespread archaeological complex defined in North America, dating from 11,100 to 10,700 C-14 years before present (BP) (13,000 to 12,600 calendar years BP)(1,2). Nearly 50 years of archaeological research point to the Clovis complex as having developed south of the North American ice sheets from an ancestral technology(3). However, both the origins and the genetic legacy of the people who manufactured Clovis tools remain under debate. It is generally believed that these people ultimately derived from Asia and were directly related to contemporary Native Americans(2). An alternative, Solutrean, hypothesis posits that the Clovis predecessors emigrated from southwestern Europe during the Last Glacial Maximum(4). Here we report the genome sequence of a male infant (Anzick-1) recovered from the Anzick burial site in western Montana. The human bones date to 10,705 +/- 35 C-14 years BP (approximately 12,707-12,556 calendar years BP) and were directly associated with Clovis tools. We sequenced the genome to an average depth of 14.4x and show that the gene flow from the Siberian Upper Palaeolithic Mal'ta population(5) into Native American ancestors is also shared by the Anzick-1 individual and thus happened before 12,600 years BP. We also show that the Anzick-1 individual is more closely related to all indigenous American populations than to any other group. Our data are compatible with the hypothesis that Anzick-1 belonged to a population directly ancestral to many contemporary Native Americans. Finally, we find evidence of a deep divergence in Native American populations that predates the Anzick-1 individual.

No large group of recently extinct placental mammals remains as evolutionarily cryptic as the approximately 280 genera grouped as 'South American native ungulates'. To Charles Darwin, who first collected their remains, they included perhaps the 'strangest animal[s] ever discovered'. Today, much like 180 years ago, it is no clearer whether they had one origin or several, arose before or after the Cretaceous/Palaeogene transition 66.2 million years ago, or are more likely to belong with the elephants and sirenians of superorder Afrotheria than with the euungulates (cattle, horses, and allies) of superorder Laurasiatheria. Morphology-based analyses have proved unconvincing because convergences are pervasive among unrelated ungulate-like placentals. Approaches using ancient DNA have also been unsuccessful, probably because of rapid DNA degradation in semitropical and temperate deposits. Here we apply proteomic analysis to screen bone samples of the Late Quaternary South American native ungulate taxa Toxodon (Notoungulata) and Macrauchenia (Litopterna) for phylogenetically informative protein sequences. For each ungulate, we obtain approximately 90% direct sequence coverage of type I collagen α1- and α2-chains, representing approximately 900 of 1,140 amino-acid residues for each subunit. A phylogeny is estimated from an alignment of these fossil sequences with collagen (I) gene transcripts from available mammalian genomes or mass spectrometrically derived sequence data obtained for this study. The resulting consensus tree agrees well with recent higher-level mammalian phylogenies. Toxodon and Macrauchenia form a monophyletic group whose sister taxon is not Afrotheria or any of its constituent clades as recently claimed, but instead crown Perissodactyla (horses, tapirs, and rhinoceroses). These results are consistent with the origin of at least some South American native ungulates from 'condylarths', a paraphyletic assembly of archaic placentals. With ongoing improvements in instrumentation and analytical procedures, proteomics may produce a revolution in systematics such as that achieved by genomics, but with the possibility of reaching much further back in time., La lista completa de autores puede consultarse en el documento o en la página web de la revista., Facultad de Ciencias Naturales y Museo

A collection of stone tools from East Anglia has been dated at around 700,000 years old, making them the the earliest signs of human activity in northern Europe by about 200,000 years. Humans were present in sunnier southern Europe before 750,000 years ago, but until now there were no traces of human activity north of the Alps before half a million years ago. The flint artefacts found at Pakefield, near Lowestoft, extend human activity in Britain and the entire northern European landmass back to an antiquity we're more used to from southern Europe. The tools are from the well known Cromer Forest-bed Formation, which has yielded Ice Age fossils for over a century. But this find was notable as the 32 worked flints, including the scraper shown on the cover, were in a clearly datable stratigraphic context. Go to tinyurl.com/d2zko for video clips of the press conference announcing this discovery. The colonization of Eurasia by early humans is a key event after their spread out of Africa, but the nature, timing and ecological context of the earliest human occupation of northwest Europe is uncertain and has been the subject of intense debate1. The southern Caucasus was occupied about 1.8 million years (Myr) ago2, whereas human remains from Atapuerca-TD6, Spain (more than 780 kyr ago)3 and Ceprano, Italy (about 800 kyr ago)4 show that early Homo had dispersed to the Mediterranean hinterland before the Brunhes–Matuyama magnetic polarity reversal (780 kyr ago). Until now, the earliest uncontested artefacts from northern Europe were much younger, suggesting that humans were unable to colonize northern latitudes until about 500 kyr ago5,6. Here we report flint artefacts from the Cromer Forest-bed Formation at Pakefield (52° N), Suffolk, UK, from an interglacial sequence yielding a diverse range of plant and animal fossils. Event and lithostratigraphy, palaeomagnetism, amino acid geochronology and biostratigraphy indicate that the artefacts date to the early part of the Brunhes Chron (about 700 kyr ago) and thus represent the earliest unequivocal evidence for human presence north of the Alps.

The successful retrieval of ancient DNA from two geographically dispersed Neanderthal skeletons1,2 has fuelled a demand for more Neanderthal DNA sequences for analysis. However, these exceptionally well-preserved specimens were geologically young and the mean annual temperature of their cave sites low, so the survival of this ancient DNA could have been due to unusually favourable conditions. Here we calculate the thermal history of a range of Holocene and Pleistocene bones whose DNA quality has been tested and find that in only very few sites with Neanderthal remains is the preservation of DNA likely to match the quality of that from the skeleton found at Mezmaiskaya Cave2. We recommend that any additional Neanderthal destined for destructive analysis should be carefully selected, taking into account its integrated thermal history.

Nature 438, 1151–1156 (2005) There are two errors in the author listings for this Letter: the surname of Anne Lafon was misspelt as 'Lafton' and the affiliation of Hiroyuki Horiuchi should have been number 16 (and not 15, as was published).

Deciding whether to farm cattle for milk or beef was just as complex in the past as it is today. Compared with meat production, dairying is a high-input, high-output, high-risk operation indicative of an intensive, sophisticated economy, but this practice is notoriously difficult to demonstrate in the archaeological record1. Here we provide evidence for the presence of milk proteins preserved in prehistoric vessels, which to our knowledge have not been detected before. This finding resolves the controversy that has surrounded dairying on the Scottish Atlantic coast during the Iron Age2,3,4,5 and indicates that farming by the early inhabitants of this harsh, marginal environment was surprisingly well developed.