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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.

Gigantopithecus blacki was a giant hominid that inhabited densely forested environments of Southeast Asia during the Pleistocene epoch1. Its evolutionary relationships to other great ape species, and the divergence of these species during the Middle and Late Miocene epoch (16-5.3 million years ago), remain unclear2,3. Hypotheses regarding the relationships between Gigantopithecus and extinct and extant hominids are wide ranging but difficult to substantiate because of its highly derived dentognathic morphology, the absence of cranial and post-cranial remains1,3-6, and the lack of independent molecular validation. We retrieved dental enamel proteome sequences from a 1.9-million-year-old G. blacki molar found in Chuifeng Cave, China7,8. The thermal age of these protein sequences is approximately five times greater than that of any previously published mammalian proteome or genome. We demonstrate that Gigantopithecus is a sister clade to orangutans (genus Pongo) with a common ancestor about 12-10 million years ago, implying that the divergence of Gigantopithecus from Pongo forms part of the Miocene radiation of great apes. In addition, we hypothesize that the expression of alpha-2-HS-glycoprotein, which has not been previously observed in enamel proteomes, had a role in the biomineralization of the thick enamel crowns that characterize the large molars in Gigantopithecus9,10. The survival of an Early Pleistocene dental enamel proteome in the subtropics further expands the scope of palaeoproteomic analysis into geographical areas and time periods previously considered incompatible with the preservation of substantial amounts of genetic information. E.C. and F.W. are supported by VILLUM FONDEN (17649) and by the European Commission through a Marie Skłodowska-Curie (MSCA) Individual Fellowship (795569). T.M.-B. is supported by BFU2017-86471-P (MINECO/FEDER, UE), NIHM grant U01 MH106874, Howard Hughes International Early Career grant, Obra Social ‘La Caixa’ and Secretaria d’Universitats i Recerca and CERCA Programme del Departament d’Economia i Coneixement de la Generalitat de Catalunya (GRC 2017 SGR 880). E.C., J.C., J.V.O., D.S. and P.G. are supported by the Marie Skłodowska-Curie European Training Network (ETN) TEMPERA, a project funded by the European Union’s EU Framework Program for Research and Innovation Horizon 2020 under grant agreement no. 722606. M.J.C. and M.M. are supported by the Danish National Research Foundation award PROTEIOS (DNRF128). Work at the Novo Nordisk Foundation Center for Protein Research is funded in part by a donation from the Novo Nordisk Foundation (NNF14CC0001). Research at Chuifeng Cave is made possible by support from the National Natural Science Foundation of China (41572023) and by a grant from the Bagui Scholar of Guangxi. M.K. was supported by a Deutsche Forschungsgemeinschaft (DFG) fellowship (KU 3467/1-1) and the Postdoctoral Junior Leader Fellowship Programme from ‘la Caixa’ Banking Foundation (LCF/BQ/PR19/11700002). M.E.A. is supported by the Independent Research Fund Denmark (7027-00147B). We thank E. Willerslev for critical reading of the manuscript, scientific support and guidance.

Brain tissue is ubiquitous in the archaeological record. Multiple, independent studies report the finding of black, resinous or shiny brain tissue, and Petrone et al. [2020 “Heat-induced Brain Vitrification from the Vesuvius Eruption in C.E. 79.” N Engl J Med. 382: 383–384; doi:10.1056/NEJMc1909867] raise the intriguing prospect of a role for vitrification in the preservation of ancient biomolecules. However, Petrone et al. (2020) have not made their raw data available, and no detailed laboratory or analytical methodology is offered. Issues of contamination and misinterpretation hampered a decade of research in biomolecular archaeology, such that addressing these sources of bias and facilitating validation of specious findings has become both routine and of paramount importance in the discipline. We argue that the evidence they present does not support their conclusion of heat-induced vitrification of human brain tissue, and that future studies should share palaeoproteomic data in an open access repository to facilitate comparative analysis of the recovery of ancient proteins and patterns of their degradation.

Funder: Greek Archaeological Committee UK (GACUK), Funder: Leventis Foundation; Id: http://dx.doi.org/10.13039/501100004117, This study compares histological preservation in archeological bones from different burial types to unravel the histotaphonomy‐to‐funerary practices relationship. Αn intraskeletal approach is also adopted to explore intraindividual (inner ear part of the petrous bone vs. upper/lower limb long bones) and intrabone (proximal vs. distal diaphysis) variability in bone collagen preservation, δ13C, and δ15N. The aim is to (a) target bones that likely retain higher amounts of collagen, (b) better understand the inner ear bone collagen isotopic signature and remodeling, and (c) assess intrabone isotopic and histological homogeneity. For the histological analysis, the data have been collected from 61 specimens (20 individuals) from the medieval/postmedieval cemetery of St. Rombout, Belgium. Thin sections have been studied using optical and scanning electron microscopy. For the collagen and isotopic data, 101 samples have been collected from 21 individuals. Distinct histological patterns are observed only in bones from single coffin burials; however, bone histology can display intraindividual and intrabone variability, which are important to account for interpretations. Collagen wt.%, δ13C, and δ15N show significant intraindividual differences but insignificant intrabone variability. This study also confirms the extraordinary nature of the petrous bone, as the inner ear bone collagen δ13C and δ15N values reflect the dietary input of the first approximately 2–3 years of life.

Next Generation Lab turns large and hitherto unstudied urban assemblages of archaeological leather and bone into a laboratory learning experience for high school students. The students, in turn, provide species identifications and thus increase knowledge on medieval and Renaissance livestock exploitation and material selection by craftsmen.

One of the greatest successes of the application of Palaeoproteomics to Archaeology is its use by a number of authors to track evidence of dairying practice, both in terms of its origin and the selection of animal species. To this end, the whey protein β-lactoglobulin entrapped in pottery and dental calculus is widely studied because it is so frequently recovered but why is it differentially preserved? Hydrolysis plays a big part in the breakdown of proteins. Therefore, it is essential to explore the role of water in degradation to uncover some of the patterns linked to protein survival. One approach to understand the hydrolytic process is to examine the molecular behaviour of this protein and in particular of the peptide most commonly recovered: T125PEVDXEALEK135. In this study, we use Molecular Dynamics, with the Amber14SB forcefield and the SPC/E water model in Gromacs 2020, to first explore the dynamics of this peptide in bulk water. Despite the difficulties in describing reactive processes with classical methods, we were able to identify geometric arrangements between water and protein residues which are similar to the ones described in the literature for protein hydrolysis. These arrangements helped to identify potential sites for hydrolysis along the bovine β-lactoglobulin T125PEVDDEALEK135 amino acid chain.

Paleoproteomics, the study of ancient proteins, is a rapidly growing field at the intersection of molecular biology, paleontology, archaeology, paleoecology, and history. Paleoproteomics research leverages the longevity and diversity of proteins to explore fundamental questions about the past. While its origins predate the characterization of DNA, it was only with the advent of soft ionization mass spectrometry that the study of ancient proteins became truly feasible. Technological gains over the past 20 years have allowed increasing opportunities to better understand preservation, degradation, and recovery of the rich bioarchive of ancient proteins found in the archaeological and paleontological records. Growing from a handful of studies in the 1990s on individual highly abundant ancient proteins, paleoproteomics today is an expanding field with diverse applications ranging from the taxonomic identification of highly fragmented bones and shells and the phylogenetic resolution of extinct species to the exploration of past cuisines from dental calculus and pottery food crusts and the characterization of past diseases. More broadly, these studies have opened new doors in understanding past human-animal interactions, the reconstruction of past environments and environmental changes, the expansion of the hominin fossil record through large scale screening of nondiagnostic bone fragments, and the phylogenetic resolution of the vertebrate fossil record. Even with these advances, much of the ancient proteomic record still remains unexplored. Here we provide an overview of the history of the field, a summary of the major methods and applications currently in use, and a critical evaluation of current challenges. We conclude by looking to the future, for which innovative solutions and emerging technology will play an important role in enabling us to access the still unexplored "dark" proteome, allowing for a fuller understanding of the role ancient proteins can play in the interpretation of the past.

Peer reviewed: True, Funder: Alexander von Humboldt Foundation; FundRef: http://dx.doi.org/10.13039/100005156, Funder: University of Texas at Austin; FundRef: http://dx.doi.org/10.13039/100008562, Funder: National Natural Science Foundation of China; FundRef: http://dx.doi.org/10.13039/501100001809, Previously, we showed that authentic peptide sequences could be obtained from 3.8-Ma-old ostrich eggshell (OES) from the site of Laetoli, Tanzania (Demarchi et al., 2016). Here, we show that the same sequences survive in a >6.5 Ma OES recovered from a palaeosteppe setting in northwestern China. The eggshell is thicker than those observed in extant species and consistent with the Liushu Struthio sp. ootaxon. These findings push the preservation of ancient proteins back to the Miocene and highlight their potential for paleontology, paleoecology, and evolutionary biology.

Mollusc shells represent excellent systems for the preservation and retrieval of genuine biomolecules from archaeological or palaeontological samples. As a consequence, the post-mortem breakdown of intracrystalline mollusc shell proteins has been extensively investigated, particularly with regard to its potential use as a "molecular clock" for geochronological applications. But despite seventy years of ancient protein research, the fundamental aspects of diagenesis-induced changes to protein structures and sequences remain elusive. In this study we investigate the degradation of intracrystalline proteins by performing artificial degradation experiments on the shell of the thorny oyster, Spondylus gaederopus, which is particularly important for archaeological research. We used immunochemistry and tandem mass tag (TMT) quantitative proteomics, a novel analytical approach that allowed us to simultaneously track patterns of structural loss and of peptide bond hydrolysis. Powdered and bleached shell samples were heated in water at four different temperatures (80, 95, 110, 140 °C) for different time durations. The structural loss of carbohydrate and protein groups was investigated by immunochemical techniques (ELLA and ELISA) and peptide bond hydrolysis was studied by tracking the changes in protein/peptide relative abundances over time using TMT quantitative proteomics. We find that heating does not induce instant organic matrix decay, but first facilitates the uncoiling of cross-linked structures, thus improving matrix detection. We calculated apparent activation energies of structural loss: Ea (carbohydrate groups) = 104.7 kJ/mol, Ea (protein epitopes) = 104.4 kJ/mol, which suggests that secondary matrix structure degradation may proceed simultaneously with protein hydrolysis. While prolonged heating at 110 °C (10 days) results in complete loss of the structural signal, surviving peptide sequences were still observed. Eight hydrolysis-prone peptide bonds were identified in the top scoring shell sequence, the uncharacterised protein LOC117318053 from Pecten maximus. Interestingly, these were not the expected "weak" bonds based on published theoretical stabilities calculated for peptides in solution. This further confirms that intracrystalline protein degradation patterns are complex and that the overall microchemical environment plays an active role in protein stability. Our TMT approach represents a major stepping stone towards developing a model for studying protein diagenesis in biomineralised systems.