Some recent non-dino papers:
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Cecily S. C. Nicholl, Jonathan P. Rio, Philip D. Mannion & Massimo Delfino (2021)
A re-examination of the anatomy and systematics of the tomistomine crocodylians from the Miocene of Italy and Malta.
Journal of Systematic Palaeontology (advance online publication)
doi: https://doi.org/10.1080/14772019.2020.1855603
https://www.tandfonline.com/doi/abs/10.1080/14772019.2020.1855603
Once a much more globally widespread crocodylian clade, Tomistominae is today represented by just one species, Tomistoma schlegelii (the false gharial), restricted to south-east Asia. Although tomistomine fossil occurrences are recognized from the early Eocene (~55âMa) onwards, their remains are often incomplete, making appropriate taxonomic classification within the group problematic. This is especially pertinent to several taxa from the Miocene of Europe, which were historically erected from fragmentary remains. Here we re-examine and describe four approximately contemporaneous taxa from Malta and Italy to determine their taxonomy and phylogenetic affinities: Melitosaurus champsoides, Tomistoma calaritanum, Tomistoma gaudense and Tomistoma lyceense. We place them into a phylogenetic analysis for the first time, comprising 70 taxa scored for 244 characters, several of which are revised or novel, and apply a number of character weighting strategies. Whereas 'Tomistoma lyceense' is deemed to be an indeterminate tomistomine, a unique combination of features confirms Melitosaurus champsoides, Tomistoma calaritanum and Tomistoma gaudense as three distinct species. These three taxa are recovered as derived tomistomines, with characters such as a posterior maxillary process between the lacrimal and nasal, large supratemporal fenestrae that are wider than long, and the posteromedial alignment of the last three premaxillary teeth, suggesting a close relationship with the approximately contemporaneous European taxa, Tomistoma lusitanica and Gavialosuchus eggenburgensis. It is unlikely that any of these species belong to Tomistoma, with the possibility that they can all be classified under Melitosaurus and Gavialosuchus. However, we retain them in open nomenclature pending reassessment of the remaining European Miocene tomistomines. Our taxonomic and phylogenetic revision helps to elucidate past tomistomine diversity in the Miocene of the Mediterranean region, prior to the groupâs extirpation, and is an important first step in resolving the complicated history of European tomistomine systematics.
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Free pdf:
Axel H. Newton, Vera Weisbecker, Andrew J. Pask & Christy A. Hipsley (2021)
Ontogenetic origins of cranial convergence between the extinct marsupial thylacine and placental gray wolf.
Communications Biology 4, Article number: 51
https://doi.org/10.1038/s42003-020-01569-x
https://www.nature.com/articles/s42003-020-01569-x
Phenotypic convergence, describing the independent evolution of similar characteristics, offers unique insights into how natural selection influences developmental and molecular processes to generate shared adaptations. The extinct marsupial thylacine and placental gray wolf represent one of the most extraordinary cases of convergent evolution in mammals, sharing striking cranial similarities despite 160âmillion years of independent evolution. We digitally reconstructed their cranial ontogeny from birth to adulthood to examine how and when convergence arises through patterns of allometry, mosaicism, modularity, and integration. We find the thylacine and wolf crania develop along nearly parallel growth trajectories, despite lineage-specific constraints and heterochrony in timing of ossification. These constraints were found to enforce distinct cranial modularity and integration patterns during development, which were unable to explain their adult convergence. Instead, we identify a developmental origin for their convergent cranial morphologies through patterns of mosaic evolution, occurring within bone groups sharing conserved embryonic tissue origins. Interestingly, these patterns are accompanied by homoplasy in gene regulatory networks associated with neural crest cells, critical for skull patterning. Together, our findings establish empirical links between adaptive phenotypic and genotypic convergence and provides a digital resource for further investigations into the developmental basis of mammalian evolution.
News:
Tasmanian tiger pups found to be extraordinary similar to wolf pups
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Open access monograph:
Richard E. Ernst, Alexander J. Dickson & Andrey Bekker (2020)(editors)
Large Igneous Provinces: A Driver of Global Environmental and Biotic Changes
Geophysical Monograph 255 (First Edition)
DOI:10.1002/9781119507444
https://agupubs.onlinelibrary.wiley.com/doi/book/10.1002/9781119507444
Online ISBN:9781119507444
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Some chapters of special interest:
David P. G. Bond & Yadong Sun (2020)
Chapter 3: Global Warming and Mass Extinctions Associated With Large Igneous Province Volcanism.
In: ÂRichard E. Ernst, Alexander J. Dickson, and Andrey Bekker (2021). Large Igneous Provinces: A Driver of Global Environmental and Biotic Changes, Geophysical Monograph 255, First Edition: 83-102
doi: Âhttps://doi.org/10.1002/9781119507444.ch3
https://agupubs.onlinelibrary.wiley.com/doi/10.1002/9781119507444.ch3
Free pdf:
https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/9781119507444.ch3
The coincidence of large igneous province (LIP) eruptions with at least three, if not all, of the Big Five biotic crises of the Phanerozoic implies that volcanism is a key driver of mass extinctions. Many LIPâinduced extinction scenarios invoke global warming, caused primarily (but not exclusively) by greenhouse gases emitted at the site of LIP emplacement and by contact metamorphism of carbonârich host rocks. Here we explore (1) the climateâchanging products of volcanism including sulfur dioxide (SO2), carbon dioxide (CO2) and methane (CH4) from eruptions, contact metamorphism, and melting (dissociation) of gas hydrates; (2) their deadly effects, including marine anoxia and thermal stress; (3) increasingly sophisticated paleotemperature proxies (e.g., Î18O of shell material) through case studies of the bestâknown LIPâwarmingâextinction nexi; and (4) global warming through the lens of the putative Anthropocene extinction.
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Ying Cui, Feifei Zhang, Jiuyuan Wang, Shijun Jiang & Shuzhong Shen (2020)
Chapter 14: Marine Anoxia and Ocean Acidification During the EndâPermian Extinction: An Integrated View From Î238U and Î44/40Ca Proxies and Earth System Modeling.
In: ÂRichard E. Ernst, Alexander J. Dickson, and Andrey Bekker (2021). Large Igneous Provinces: A Driver of Global Environmental and Biotic Changes, Geophysical Monograph 255, First Edition: 325-340
doi: https://doi.org/10.1002/9781119507444.ch14
https://agupubs.onlinelibrary.wiley.com/doi/10.1002/9781119507444.ch14
Free pdf:
https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/9781119507444.ch14
The largest mass extinction event in the Phanerozoic, known as the endâPermian mass extinction (or EPME, ca. 252 Ma) is coincident with the main eruption phase of Siberian Traps volcanism (ca. 252 to 250 Ma), a large igneous province (LIP). This LIP is estimated to have a volume larger than 2 Ã 106 km3 and to have released both mantle carbon dioxide (CO2) through extrusions and thermogenic methane (CH4) and carbon dioxide (CO2) through intrusions. The climatic consequences of these greenhouse gases is detrimental to both marine and terrestrial life and may have delayed the recovery of ecosystems after the extinction. Quantitatively, the amount of CO2 released can be estimated using global carbon (C) cycle model or plant and soilâbased proxies with varying time resolution. In light of the recent advances in geochemical proxies of ocean anoxia and acidification, we review the latest uranium isotopes (Î238U) and calcium isotope (Î44/40Ca) records and Earth system modeling results to summarize the environmental response to the forcing of increased atmospheric CO2 concentrations. The extent of increase in oceanic anoxic area can be estimated by Î238U, and the Î44/40Ca records may be used to evaluate ocean acidification. This evidence suggests that excessive nutrient load in the ocean (decreased strength of meridional overturning circulation) and ocean acidification in poorly buffered seawater (potentially triggered by the Siberian Traps LIP) worked together to create the most severe biological crisis and delayed recovery of life in the Earth's history.
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Jun Chen & YiâGang Xu (2020)
Chapter 18: Permian Large Igneous Provinces and Their Paleoenvironmental Effects.
In: ÂRichard E. Ernst, Alexander J. Dickson, and Andrey Bekker (2021). Large Igneous Provinces: A Driver of Global Environmental and Biotic Changes, Geophysical Monograph 255, First Edition: 417-434
doi: https://doi.org/10.1002/9781119507444.ch18
https://agupubs.onlinelibrary.wiley.com/doi/10.1002/9781119507444.ch18
The Permian Period was characterized by a series of largeâscale volcanic eruptions, including the emplacement of at least five mafic Large Igneous Provinces (LIPs: SkagerrakâCentered, Tarim, Panjal, Emeishan, and Siberian) and two silicic LIPs (KennedyâConnorsâAuburn and Choiyoi). Global climate change from a glacial (icehouse) state in the latest CarboniferousâEarly Permian to nonglacial (greenhouse) state in the Late Permian and PermianâTriassic interval, and major biotic change such as the endâGuadalupian and endâPermian mass extinctions, also occurred in this interval. Whether these climate and biotic changes, along with other paleoenvironmental perturbations (e.g., carbon cycle, ocean chemistry, and terrestrial weathering), were triggered by or in certain ways associated with contemporaneous LIP volcanism need to be examined on a caseâbyâcase basis. In this chapter, we summarize some recent advances in the studies of the Permian LIPs, contemporary paleoenvironmental conditions, and their potential associations with biodiversity changes, especially the endâGuadalupian and endâPermian mass extinctions. Our analyses suggest (1) high volume of volcanic products, (2) short duration, and (3) widespread sill intrusions that led to contact metamorphism with wall rocks (e.g., evaporates, organicârich sediments, petroleum reservoir) are the pivotal factors determining the paleoenvironmental effects of LIP volcanism. The combination of these three characteristics enabled the Siberian Traps volcanism to be the most deadly, and potentially can affect the contemporaneous environment and biota on a global scale. Other mafic and silicic LIPs in the Permian, by contrast, either do not possess any of, or are only partly in accord with, these determining factors. Therefore, their impact on contemporaneous climate and ecosystem is limited.
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Free pdf:
Justin S. Tweet and Vincent L. Santucci (2021)
From microfossils to megafauna: an overview of the taxonomic diversity of National Park Service fossils.
In: Lucas, S. G., Hunt, A. P. & Lichtig, A. J., 2021, Fossil Record 7. New Mexico Museum of Natural History and Science Bulletin 82: 437-457
https://irma.nps.gov/DataStore/Reference/Profile/2283752Â
From microfossils to megafauna: an overview of the taxonomic diversity of National Park Service fossils.
In: Lucas, S. G., Hunt, A. P. & Lichtig, A. J., 2021, Fossil Record 7. New Mexico Museum of Natural History and Science Bulletin 82: 437-457
https://irma.nps.gov/DataStore/Reference/Profile/2283752Â
The vast taxonomic breadth of the National Park Service (NPS)âs fossil record has never been systematically examined until now. Paleontological resources have been documented within 277 NPS units and affiliated areas as of the date of submission of this publication (Summer 2020). The paleontological records of these units include fossils from dozens of high-level taxonomic divisions of plants, invertebrates, and vertebrates, as well as many types of ichnofossils and microfossils. Using data and archives developed for the NPS Paleontology Synthesis Project (PSP) that began in 2012, it is possible to examine and depict the broad taxonomic diversity of these paleontological resources. The breadth of the NPS fossil record ranges from Proterozoic microfossils and stromatolites to Quaternary plants, mollusks, and mammals. The most diverse taxonomic records have been found in parks in the western United States and Alaska, which are generally recognized for their long geologic records. Conifers, angiosperms, corals, brachiopods, bivalves, gastropods, artiodactyls, invertebrate burrows, and foraminiferans are among the most frequently reported fossil groups. Small to microscopic fossils such as pollen, spores, the bones of small vertebrates, and the tests of marine plankton are underrepresented because of their size and the specialized equipment and techniques needed to study them. The improved capacity to rapidly analyze the fossil record of NPS units granted by the PSP is valuable for pursuing resource management goals, and for making the wealth of NPS paleontological resources more available for scientific, educational, and interpretive purposes.
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