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  • 1.
    Bengtson, Stefan
    et al.
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Rasmussen, Birger
    School of Earth Sciences, The University of Western Australia, Perth.
    Zi, Jian-Wei
    State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan.
    Fletcher, Ian R.
    School of Earth Sciences, The University of Western Australia, Perth.
    Gehling, James G.
    Palaeontology, South Australian Museum, Adelaide.
    Runnegar, Bruce
    Department of Earth, Planetary and Space Sciences, University of California, Los Angeles.
    Eocene animal trace fossils in 1.7-billion-year-old metaquartzites2021Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 118, nr 40, s. 1-8, artikkel-id e2105707118Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Paleoproterozoic (1.7 Ga [billion years ago]) metasedimentary rocks of the Mount Barren Group in southwestern Australia contain burrows indistinguishable from ichnogenera Thalassinoides, Ophiomorpha, Teichichnus, and Taenidium, known from firmgrounds and softgrounds. The metamorphic fabric in the host rock is largely retained, and because the most resilient rocks in the sequence, the metaquartzites, are too hard for animal burrowing, the trace fossils have been interpreted as predating the last metamorphic event in the region. Since this event is dated at 1.2 Ga, this would bestow advanced animals an anomalously early age. We have studied the field relationships, petrographic fabric, and geochronology of the rocks and demonstrate that the burrowing took place during an Eocene transgression over a weathered regolith. At this time, the metaquartzites of the inundated surface had been weathered to friable sandstones or loose sands (arenized), allowing for animal burrowing. Subsequent to this event, there was a resilicification of the quartzites, filling the pore space with syntaxial quartz cement forming silcretes. Where the sand grains had not been dislocated during weathering, the metamorphic fabric was seemingly restored, and the rocks again assumed the appearance of hard metaquartzites impenetrable to animal burrowing.

    Fulltekst (pdf)
    fulltext
  • 2. Brace, Selina
    et al.
    Palkopoulou, Eleftheria
    Dalen, Love
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Lister, Adrian M.
    Miller, Rebecca
    Otte, Marcel
    Germonpre, Mietje
    Blockley, Simon P. E.
    Stewart, John R.
    Barnes, Ian
    Serial population extinctions in a small mammal indicate Late Pleistocene ecosystem instability2012Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 109, nr 50, s. 20532-20536Artikkel i tidsskrift (Fagfellevurdert)
  • 3.
    Cheng, Yalin
    et al.
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China;;College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China;.
    Miller, Matthew J.
    Conservation Genetics Division, Reneco International Wildlife Consultants LLC, Abu Dhabi, United Arab Emirates;;University of Alaska Museum, University of Alaska Fairbanks, Fairbanks, AK 99775;.
    Zhang, Dezhi
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China;.
    Xiong, Ying
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China;;College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China;.
    Hao, Yan
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China;;College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China;.
    Jia, Chenxi
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China;.
    Cai, Tianlong
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China;;College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China;.
    Li, Shou-Hsien
    Department of Life Sciences, National Taiwan Normal University, Taipei 116, Taiwan, China;.
    Johansson, Ulf S.
    Naturhistoriska riksmuseet, Enheten för zoologi. Department of Zoology, Swedish Museum of Natural History, SE-104 05 Stockholm, Sweden;.
    Liu, Yang
    State Key Laboratory of Biocontrol, Department of Ecology/School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China;.
    Chang, Yongbin
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China;;College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China;.
    Song, Gang
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China;.
    Qu, Yanhua
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China;.
    Lei, Fumin
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China;;College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China;;Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650201, China.
    Parallel genomic responses to historical climate change and high elevation in East Asian songbirds2021Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 118, nr 50Artikkel i tidsskrift (Fagfellevurdert)
  • 4.
    Chi Fru, Ernest
    et al.
    Stockholm University, Department of Geological Sciences.
    Rodríguez, Nathalie
    Stockholm University Department of Geological Sciences.
    Partin, Camille
    University of Saskatchewan, Canada.
    Lalonde, Stefan
    Université de Bretagne Occidentale, France.
    Andersson, Per
    Naturhistoriska riksmuseet, Enheten för geovetenskap.
    Weiss, Dominik
    Imperial College, London, UK.
    El Albani, Abderrazak
    Université de Poitiers, France.
    Rodushkin, Ilia
    ALS Scandinavia, Sweden.
    Konhauser, Kurt
    University of Alberta, Canada.
    Cu isotopes in marine black shales record the Great Oxidation Event2016Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 113, nr 18, s. 4941-4946Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The oxygenation of the atmosphere ∼2.45–2.32 billion years ago (Ga) is one of the most significant geological events to have affected Earth’s redox history. Our understanding of the timing and processes surrounding this key transition is largely dependent on the development of redox-sensitive proxies, many of which remain unexplored. Here we report a shift from negative to positive copper isotopic compositions (δ65CuERM-AE633) in organic carbon-rich shales spanning the period 2.66–2.08 Ga. We suggest that, before 2.3 Ga, a muted oxidative supply of weathering-derived copper enriched in 65Cu, along with the preferential removal of 65Cu by iron oxides, left seawater and marine biomass depleted in 65Cu but enriched in 63Cu. As banded iron formation deposition waned and continentally sourced Cu became more important, biomass sampled a dissolved Cu reservoir that was progressively less fractionated relative to the continental pool. This evolution toward heavy δ65Cu values coincides with a shift to negative sedimentary δ56Fe values and increased marine sulfate after the Great Oxidation Event (GOE), and is traceable through Phanerozoic shales to modern marine settings, where marine dissolved and sedimentary δ65Cu values are universally positive. Our finding of an important shift in sedimentary Cu isotope compositions across the GOE provides new insights into the Precambrian marine cycling of this critical micronutrient, and demonstrates the proxy potential for sedimentary Cu isotope compositions in the study of biogeochemical cycles and oceanic redox balance in the past.

  • 5. Cote, Susanne M.
    et al.
    Werdelin, Lars
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Seiffert, E. R.
    Barry, J. C.
    The enigmatic Early Miocene mammal Kelba and its relationship to the order Ptolemaiida2007Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 104, s. 5510-5515Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Kelba quadeemae, a fossil mammal from the Early Miocene of East Africa, was originally named on the basis of three isolated upper molars. Kelba has previously been interpreted as a creodont, a pantolestid, an insectivoran, and a hemigaline viverrid. The true affinities of this taxon have remained unclear because of the limited material and its unique morphology relative to other Miocene African mammals. New material of Kelba from several East African Miocene localities, most notably a skull from the Early Miocene locality of Songhor in Western Kenya, permits analysis of the affinities of Kelba and documents the lower dentition of this taxon. Morphological comparison of this new material clearly demonstrates that Kelba is a member of the order Ptolemaiida, a poorly understood group whose fossil record was previously restricted to the Oligocene Fayum deposits of northern Egypt. Phylogenetic analysis supports the monophyly of the Ptolemaiida, including Kelba, and recovers two monophyletic clades within the order. We provide new family names for these groups and an emended diagnosis for the order. The discovery of ptolemaiidans from the Miocene of East Africa is significant because it extends the known temporal range of the order by >10 million years and the geographic range by >3,200 km. Although the higher-level affinities of the Ptolemaiida remain obscure, their unique morphology and distribution through a larger area of Africa (and exclusively Africa) lend support to the idea that Ptolemaiida may have an ancient African origin.

  • 6.
    Dalen, Love
    et al.
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Nystrom, Veronica
    Valdiosera, Cristina
    Germonpre, Mietje
    Sablin, Mikhail
    Turner, Elaine
    Angerbjorn, Anders
    Arsuaga, Juan Luis
    Gotherstrom, Anders
    Ancient DNA reveals lack of postglacial habitat tracking in the arctic fox2007Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 104, nr 16, s. 6726-6729Artikkel i tidsskrift (Fagfellevurdert)
  • 7.
    Feuerborn, T R
    et al.
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Carmagnini, A
    Losey, R J
    Nomokonova, T
    Askeyev, A
    Askeyev, I
    Askeyev, O
    Antipina, E E
    Appelt, M
    Bachura, O P
    Beglane, F
    Bradley, D G
    Daly, K G
    Gopalakrishnan, S
    Gregersen, K M
    Guo, C X
    Gusev, A V
    Jones, C
    Kosintsev, P A
    Kuzmin, Y V
    Mattiangeli, V
    Perri, A R
    Plekhanov, A V
    Ramos-Madrigal, J
    Schmidt, A L
    Shaymuratova, D
    Smith, O
    Yavorskaya, L V
    Zhang, G J
    Willerslev, E
    Meldgaard, M
    Gilbert, M T P
    Larson, G
    Dalen, L
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Hansen, A J
    Sinding, M H S
    Frantz, L
    Modern Siberian dog ancestry was shaped by several thousand years of Eurasian-wide trade and human dispersal2021Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 118, nr 39Artikkel i tidsskrift (Fagfellevurdert)
    Fulltekst (pdf)
    fulltext
  • 8. Gaya, Ester
    et al.
    Fernández-Brime, Samantha
    Naturhistoriska riksmuseet, Enheten för botanik.
    Vargas, Reinaldo
    Lachlan, Robert F.
    Gueidan, Cécile
    Ramírez-Mejía, Martín
    Lutzoni, François
    The adaptive radiation of lichen-forming Teloschistaceae is associated with sunscreening pigments and a bark-to-rock substrate shift2015Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 112, nr 37, s. 11600-11605Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Adaptive radiations play key roles in the generation of biodiversity and biological novelty, and therefore understanding the factors that drive them remains one of the most important challenges of evolutionary biology. Although both intrinsic innovations and extrinsic ecological opportunities contribute to diversification bursts, few studies have looked at the synergistic effect of such factors. Here we investigate the Teloschistales (Ascomycota), a group of >1,000 lichenized species with variation in species richness and phenotypic traits that hinted at a potential adaptive radiation. We found evidence for a dramatic increase in diversification rate for one of four families within this order—Teloschistaceae—which occurred ∼100 Mya (Late Cretaceous) and was associated with a switch from bark to rock and from shady to sun-exposed habitats. This adaptation to sunny habitats is likely to have been enabled by a contemporaneous key novel phenotypic innovation: the production in both vegetative structure (thallus) and fruiting body (apothecia) of anthraquinones, secondary metabolites known to protect against UV light. We found that the two ecological factors (sun exposure and rock substrate) and the phenotypic innovation (anthraquinones in the thallus) were all significant when testing for state-dependent shifts in diversification rates, and together they seem likely to be responsible for the success of the Teloschistaceae, one of the largest lichen-forming fungal lineages. Our results support the idea that adaptive radiations are driven not by a single factor or key innovation, but require a serendipitous combination of both intrinsic biotic and extrinsic abiotic and ecological factors.

  • 9. Gilbert, M Thomas P
    et al.
    Drautz, Daniela I
    Lesk, Arthur M
    Ho, Simon Y W
    Qi, Ji
    Ratan, Aakrosh
    Hsu, Chih-Hao
    Sher, Andrei
    Dalén, Love
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Götherström, Anders
    Tomsho, Lynn P
    Rendulic, Snjezana
    Packard, Michael
    Campos, Paula F
    Kuznetsova, Tatyana V
    Shidlovskiy, Fyodor
    Tikhonov, Alexei
    Willerslev, Eske
    Iacumin, Paola
    Buigues, Bernard
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    Germonpré, Mietje
    Kosintsev, Pavel
    Nikolaev, Vladimir
    Nowak-Kemp, Malgosia
    Knight, James R
    Irzyk, Gerard P
    Perbost, Clotilde S
    Fredrikson, Karin M
    Harkins, Timothy T
    Sheridan, Sharon
    Miller, Webb
    Schuster, Stephan C
    Intraspecific phylogenetic analysis of Siberian woolly mammoths using complete mitochondrial genomes.2008Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 105, nr 24, s. 8327-32Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We report five new complete mitochondrial DNA (mtDNA) genomes of Siberian woolly mammoth (Mammuthus primigenius), sequenced with up to 73-fold coverage from DNA extracted from hair shaft material. Three of the sequences present the first complete mtDNA genomes of mammoth clade II. Analysis of these and 13 recently published mtDNA genomes demonstrates the existence of two apparently sympatric mtDNA clades that exhibit high interclade divergence. The analytical power afforded by the analysis of the complete mtDNA genomes reveals a surprisingly ancient coalescence age of the two clades, approximately 1-2 million years, depending on the calibration technique. Furthermore, statistical analysis of the temporal distribution of the (14)C ages of these and previously identified members of the two mammoth clades suggests that clade II went extinct before clade I. Modeling of protein structures failed to indicate any important functional difference between genomes belonging to the two clades, suggesting that the loss of clade II more likely is due to genetic drift than a selective sweep.

  • 10.
    Gulick, Sean, P.S.
    et al.
    University of Texas at Austin.
    Bralower, Timothy J.
    Pennsylvania State University.
    Ormö, Jens
    Instituto Nacional de Técnica Aeroespacial-Spanish National Research Council.
    Hall, Brendon
    Enthought, Inc..
    Grice, Kliti
    Curtin University.
    Schaefer, Bettina
    Curtin University.
    Lyons, Shelby
    Pennsylvania State University.
    Freeman, Katherine
    Pennsylvania State University.
    Morgan, Joahha
    Imperial College London.
    Artemieva, Natalia
    Planetary Science Institute, Tucson.
    Kaskes, Pim
    Vrije Universiteit Brussel.
    de Graaff, Sietze
    Vrije Universiteit Brussel.
    Whalen, Michael T.
    University of Alaska Fairbanks.
    Collins, Gareth S.
    Imperial College London.
    Tikoo, Sonia M.
    Rutgers University.
    Verhagen, Christina
    Rutgers University.
    Christeson, Gail L.
    University of Texas at Austin.
    Claeys, Philippe
    Vrije Universiteit Brussel.
    Coolen, Marco J. L.
    Curtin University.
    Goderis, Steven
    Imperial College London.
    Goto, Kazuhisa
    Tohoku University.
    Grieve, Richard A. F.
    University of Western Ontario.
    McCall, Naoma
    University of Texas at Austin.
    Osinski, Gordon R.
    University of Western Ontario.
    Rae, Auriol S. P.
    Imperial College London.
    Riller, Ulrich
    Universität Hamburg.
    Smit, Jan
    Vrije Universiteit Amsterdam.
    Vajda, Vivi
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    Wittmann, Axel
    Arizona State University.
    The first day of the Cenozoic2019Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 116, s. 19342-19351Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Highly expanded Cretaceous–Paleogene (K-Pg) boundary section from the Chicxulub peak ring, recovered by International Ocean Discovery Program (IODP) –International Continental Scientific Drilling Program (ICDP) Expedition 364, provides an unprecedented window into the immediate aftermath of the impact. Site M0077 includes ∼130 m of impact melt rock and suevite deposited the first day of the Cenozoic covered by <1 m of micrite-rich carbonate deposite over subsequent weeks to years. We present an interpreted series of events based on analyses of these drill cores. Within minutes of the impact, centrally uplifted basement rock collapsed outward to forma peak ring capped in melt rock. Within tens of minutes, the peak ring was covered in ∼40 m of brecciated impact melt rock and coarsegrained suevite, including clasts possibly generated by melt–water interactions during ocean resurge. Within an hour, resurge crested the peak ring, depositing a 10-m-thick layer of suevite with increased particle roundness and sorting. Within hours, the full resurge deposit formed through settling and seiches, resulting in an 80-m-thick fining-upward, sorted suevite in the flooded crater. Within a day, the reflected rim-wave tsunami reached the crater, depositing a cross-bedded sand-to-fine gravel layer enriched in polycyclic aromatic hydrocarbons overlain by charcoal fragments. Generation of a deep crater open to the ocean allowed rapid flooding and sediment accumulation rates among the highest known in the geologic record. The high-resolution section provides insight into the impact environmental effects, including charcoal as evidence for impactinduced wildfires and a paucity of sulfur-rich evaporites from the target supporting rapid global cooling and darkness as extinction mechanisms.

  • 11. Jønsson, Knud A
    et al.
    Fabre, Pierre-Henri
    Fritz, Susanne A
    Etienne, Rampal S
    Ricklefs, Robert E
    Jørgensen, Tobias B
    Fjeldså, Jon
    Rahbek, Carsten
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    Woog, Friederike
    Pasquet, Eric
    Irestedt, Martin
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Ecological and evolutionary determinants for the adaptive radiation of the Madagascan vangas.2012Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 109, nr 17, s. 6620-5Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Adaptive radiation is the rapid diversification of a single lineage into many species that inhabit a variety of environments or use a variety of resources and differ in traits required to exploit these. Why some lineages undergo adaptive radiation is not well-understood, but filling unoccupied ecological space appears to be a common feature. We construct a complete, dated, species-level phylogeny of the endemic Vangidae of Madagascar. This passerine bird radiation represents a classic, but poorly known, avian adaptive radiation. Our results reveal an initial rapid increase in evolutionary lineages and diversification in morphospace after colonizing Madagascar in the late Oligocene some 25 Mya. A subsequent key innovation involving unique bill morphology was associated with a second increase in diversification rates about 10 Mya. The volume of morphospace occupied by contemporary Madagascan vangas is in many aspects as large (shape variation)--or even larger (size variation)--as that of other better-known avian adaptive radiations, including the much younger Galapagos Darwin's finches and Hawaiian honeycreepers. Morphological space bears a close relationship to diet, substrate use, and foraging movements, and thus our results demonstrate the great extent of the evolutionary diversification of the Madagascan vangas.

  • 12. Klawonn, Isabell
    et al.
    Van den Wyngaert, Silke
    Parada, Alma E.
    Arandia-Gorostidi, Nestor
    Whitehouse, Martin J.
    Naturhistoriska riksmuseet, Enheten för geovetenskap.
    Grossart, Hans-Peter
    Dekas, Anne E.
    Characterizing the “fungal shunt”: Parasitic fungi on diatoms affect carbon flow and bacterial communities in aquatic microbial food webs2021Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490Artikkel i tidsskrift (Fagfellevurdert)
  • 13. Kusiak, M.A.
    et al.
    Dunkley, D.J.
    Wirth, R.
    Whitehouse, Martin J.
    Naturhistoriska riksmuseet, Enheten för geovetenskap.
    Wilde, S.A.
    Marquardt, K.
    Metallic lead nanospheres discovered in ancient zircons.2015Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 112, s. 4958-4963Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Zircon (ZrSiO4) is the most commonly used geochronometer, preserving age and geochemical information through a wide range of geological processes. However, zircon U–Pb geochronology can be affected by redistribution of radiogenic Pb, which is incompatible in the crystal structure. This phenomenon is particularly common in zircon that has experienced ultra-high temperature metamorphism, where ion imaging has revealed submicrometer domains that are sufficiently heterogeneously distributed to severely perturb ages, in some cases yielding apparent Hadean (>4 Ga) ages from younger zircons. Documenting the composition and mineralogy of these Pb-enriched domains is essential for understanding the processes of Pb redistribution in zircon and its effects on geochronology. Using high-resolution scanning transmission electron microscopy, we show that Pb-rich domains previously identified in zircons from East Antarctic granulites are 5–30 nm nanospheres of metallic Pb. They are randomly distributed with respect to zircon crystallinity, and their association with a Ti- and Al-rich silica melt suggests that they represent melt inclusions generated during ultra-high temperature metamorphism. Metallic Pb is exceedingly rare in nature and previously has not been reported in association with high-grade metamorphism. Formation of these metallic nanospheres within annealed zircon effectively halts the loss of radiogenic Pb from zircon. Both the redistribution and phase separation of radiogenic Pb in this manner can compromise the precision and accuracy of U–Pb ages obtained by high spatial resolution methods.                           

    Fulltekst (pdf)
    fulltext
  • 14. Müller, Johannes
    et al.
    Scheyer, Torsten M
    Head, Jason J
    Barrett, Paul M
    Werneburg, Ingmar
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    Pol, Diego
    Sánchez-Villagra, Marcelo R
    Homeotic effects, somitogenesis and the evolution of vertebral numbers in recent and fossil amniotes.2010Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 107, nr 5, s. 2118-23Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The development of distinct regions in the amniote vertebral column results from somite formation and Hox gene expression, with the adult morphology displaying remarkable variation among lineages. Mammalian regionalization is reportedly very conservative or even constrained, but there has been no study investigating vertebral count variation across Amniota as a whole, undermining attempts to understand the phylogenetic, ecological, and developmental factors affecting vertebral column variation. Here, we show that the mammalian (synapsid) and reptilian lineages show early in their evolutionary histories clear divergences in axial developmental plasticity, in terms of both regionalization and meristic change, with basal synapsids sharing the conserved axial configuration of crown mammals, and basal reptiles demonstrating the plasticity of extant taxa. We conducted a comprehensive survey of presacral vertebral counts across 436 recent and extinct amniote taxa. Vertebral counts were mapped onto a generalized amniote phylogeny as well as individual ingroup trees, and ancestral states were reconstructed by using squared-change parsimony. We also calculated the relationship between presacral and cervical numbers to infer the relative influence of homeotic effects and meristic changes and found no correlation between somitogenesis and Hox-mediated regionalization. Although conservatism in presacral numbers characterized early synapsid lineages, in some cases reptiles and synapsids exhibit the same developmental innovations in response to similar selective pressures. Conversely, increases in body mass are not coupled with meristic or homeotic changes, but mostly occur in concert with postembryonic somatic growth. Our study highlights the importance of fossils in large-scale investigations of evolutionary developmental processes.

  • 15. Palkopoulou, Eleftheria
    et al.
    Lipson, Mark
    Mallick, Swapan
    Nielsen, Svend
    Rohland, Nadin
    Baleka, Sina
    Karpinski, Emil
    Ivancevici, Atma M.
    To, Thu-Hien
    Kortschak, Daniel
    Raison, Joy M.
    Qu, Zhipeng
    Chin, Tat-Jun
    Alt, Kurt W.
    Claesson, Stefan
    Dalén, Love
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    MacPhee, Ross D. E.
    Meller, Harald
    Rocar, Alfred L.
    Ryder, Oliver A.
    Heiman, David
    Young, Sarah
    Breen, Matthew
    Williams, Christina
    Aken, Bronwen L.
    Ruffier, Magali
    Karlsson, Elinor
    Johnson, Jeremy
    Di Palma, Federica
    Alfoldi, Jessica
    Adelsoni, David L.
    Mailund, Thomas
    Munch, Kasper
    Lindblad-Toh, Kerstin
    Hofreiter, Michael
    Poinar, Hendrik
    Reich, David
    A comprehensive genomic history of extinct and living elephants2018Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 115, nr 11, s. E2566-E2574Artikkel i tidsskrift (Fagfellevurdert)
  • 16.
    Qu, Yanhua
    et al.
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
    Chen, Chunhai
    Chen, Xiumin
    Hao, Yan
    She, Huishang
    Wang, Mengxia
    Ericson, Per G P
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Lin, Haiyan
    Cai, Tianlong
    Song, Gang
    Jia, Chenxi
    Chen, Chunyan
    Zhang, Hailin
    Li, Jiang
    Liang, Liping
    Wu, Tianyu
    Zhao, Jinyang
    Gao, Qiang
    Zhang, Guojie
    Zhai, Weiwei
    Zhang, Chi
    Zhang, Yong E.
    Lei, Fumin
    The evolution of ancestral and species-specific adaptations in snowfinches at the Qinghai-Tibet Plateau2021Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 10.1073/pnas.2012398118, nr 13, s. e2012398118-e2012398118Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Species in a shared environment tend to evolve similar adaptations under the influence of their phylogenetic context. Using snowfinches, a monophyletic group of passerine birds (Passeridae), we study the relative roles of ancestral and species-specific adaptations to an extreme high-elevation environment, the Qinghai–Tibet Plateau. Our ancestral trait reconstruction shows that the ancestral snowfinch occupied high elevations and had a larger body mass than most nonsnowfinches in Passeridae. Subsequently, this phenotypic adaptation diversified in the descendant species. By comparing high-quality genomes from representatives of the three phylogenetic lineages, we find that about 95% of genes under positive selection in the descendant species are different from those in the ancestor. Consistently, the biological functions enriched for these species differ from those of their ancestor to various degrees (semantic similarity values ranging from 0.27 to 0.5), suggesting that the three descendant species have evolved divergently from the initial adaptation in their common ancestor. Using a functional assay to a highly selective gene, DTL, we demonstrate that the nonsynonymous substitutions in the ancestor and descendant species have improved the repair capacity of ultraviolet-induced DNA damage. The repair kinetics of the DTL gene shows a twofold to fourfold variation across the ancestor and the descendants. Collectively, this study reveals an exceptional case of adaptive evolution to high-elevation environments, an evolutionary process with an initial adaptation in the common ancestor followed by adaptive diversification of the descendant species.

  • 17.
    Sha, Jingeng
    et al.
    State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Paleontology, Nanjing 210008, China.
    Olsen, Paul E.
    Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10968.
    Pan, Yanhong
    State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Paleontology, Nanjing 210008, China.
    Xu, Daoyi
    Institute of Geology, China Earthquake Administration, Beijing 100029, China.
    Wang, Yaqiang
    State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Paleontology, Nanjing 210008, China.
    Zhang, Xiaolin
    Chinese Academy of Sciences Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Heifei 230026, China.
    Yao, Xiaogang
    State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Paleontology, Nanjing 210008, China.
    Vajda, Vivi
    Naturhistoriska riksmuseet, Enheten för paleobiologi. Department of Geology, Lund University, Sweden.
    Triassic–Jurassic climate in continental high-latitude Asia was dominated by obliquity-paced variations (Junggar Basin, Ürümqi, China)2015Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 112, nr 12, s. 3624-3629Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Empirical constraints on orbital gravitational solutions for the Solar System can be derived from the Earth’s geological record of past climates. Lithologically based paleoclimate data from the thick, coal-bearing, fluvial-lacustrine sequences of the Junggar Basin of Northwestern China (paleolatitude ∼60°) show that climate variability of the warm and glacier-free high latitudes of the latest Triassic–Early Jurassic (∼198–202 Ma) Pangea was strongly paced by obliquity-dominated (∼40 ky) orbital cyclicity, based on an age model using the 405-ky cycle of eccentricity. In contrast, coeval low-latitude continental climate was much more strongly paced by climatic precession, with virtually no hint of obliquity. Although this previously unknown obliquity dominance at high latitude is not necessarily unexpected in a high CO2 world, these data deviate substantially from published orbital solutions in period and amplitude for eccentricity cycles greater than 405 ky, consistent with chaotic diffusion of the Solar System. In contrast, there are indications that the Earth–Mars orbital resonance was in today’s 2-to-1 ratio of eccentricity to inclination. These empirical data underscore the need for temporally comprehensive, highly reliable data, as well as new gravitational solutions fitting those data.

    Fulltekst (pdf)
    fulltext
  • 18. Yates, J A F
    et al.
    Velsko, I M
    Aron, F
    Posth, C
    Hofman, C A
    Austin, R M
    Parker, C E
    Mann, A E
    Nagele, K
    Arthur, K W
    Arthur, J W
    Bauer, C C
    Crevecoeur, I
    Cupillard, C
    Curtis, M C
    Dalen, L
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Bonilla, M D Z
    Fernandez-Lomana, J C D
    Drucker, D G
    Escriva, E E
    Francken, M
    Gibbon, V E
    Morales, M R G
    Mateu, A G
    Harvatit, K
    Henry, A G
    Humphrey, L
    Menendez, M
    Mihailovic, D
    Peresani, M
    Moroder, S R
    Roksandic, M
    Rougier, H
    Sazelova, S
    Stock, J T
    Straus, L G
    Svoboda, J
    Tessmann, B
    Walker, M J
    Power, R C
    Lewis, C M
    Sankaranarayanan, K
    Guschanski, K
    Wrangham, R W
    Dewhirst, F E
    Salazar-Garcia, D C
    Krause, J
    Herbig, A
    Warinner, C
    The evolution and changing ecology of the African hominid oral microbiome2021Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 118, nr 20Artikkel i tidsskrift (Fagfellevurdert)
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