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Introducing palaeolithobiology
No full textA growing literature of deep but also surficial fossilized remains of lithobiological life, often associated with igneous rocks, necessitates the unfolding of a sub-discipline within paleobiology. Here, we introduce the term paleolithobiology as the new auxiliary sub-discipline under which fossilized lithobiology should be handled. We present key criteria that distinguish the paleolithobiological archive from the traditional one and discuss sample strategies as well as scientific perspectives. A majority of paleolithobiological material consists of deep biosphere fossils, and in order to highlight the relevance of these, we present new data on fungal fossils from the Lockne impact crater. Fungal fossils in the Lockne drill cores have been described previously but here we provide new insights into the presence of reproductive structures that indicate the fungi to be indigenous. We also show that these fungi frequently dissolve and penetrate secondary calcite, delineating the role lithobionts plays in geobiological cycles. We hope that the formalization of the sub-discipline paleolithobiology will not only highlight an overlooked area of paleobiology as well as simplify future studies of endo- and epilithic fossil material, but also improve our understanding of the history of the deep biosphere
δ60Ni and δ13C Composition of Serpentinites and Carbonates of the Tekirova Ophiolite, Turkey, and Meatiq Ophiolite, Egypt
No full textNickel isotope fractionation patterns in continental ultramafic environments generally show a depletion of δ60 Ni in weathered rocks and an enrichment in bedrock samples. The present study focuses on stable Ni isotope fractionation patterns in carbonate-rich, ultramafic ophiolite samples with concomitant fluids at an active serpentinization site in southwestern Turkey, with a comparison to results from an inactive serpentinization site in the Eastern Desert of Egypt with carbonate-rich samples. All solid phase data from the inactive serpentinization area are consistent with previously reported values from serpentinites, whereas the solid precipitates in the active area (SW Turkey) give values slightly heavier than previously reported data. However, the Ni isotopic signatures in the active serpentinization system likely reflect the scavenging of light Ni by iron oxide and carbonate precipitation, as has been previously demonstrated in laboratory coprecipitation experiments. It is also possible that the active system results resemble previous laboratory experimental results that show a relatively strong initial fractionation between fluids and solids, which then diminishes with time due to aging of the precipitates
Expanded Explorations of the Dinaledi Subsystem,Rising Star Cave System, South Africa
No full textThe Dinaledi Chamber of the Rising Star cave system has yielded a large assemblage of fossil hominin material, attributed to Homo naledi. The unusual taphonomic and geological situation of the assemblage suggested that the remains may have been deliberately deposited in the chamber. However, the route and mechanism of deposition of the remains within the Dinaledi Chamber are still uncertain. During the 2017—2018 field seasons, we expanded explorations of the passages surrounding the Dinaledi Chamber. These explorations improved our understandingof the cave’s spatial complexity, necessitating a revision of the way the spaces are named and described. The work supported the hypothesis that there is no alternate entrance into the system other than the Chute. The work also identified new fossil deposits in several remote passages, three of which contain material attributable to H. naledi. Here, we clarify the definition of the Dinaledi Subsystem and provide terminology for new fossil localities found in this portion of the Rising Star cave system. These results emphasize the complex depositional environment of the Dinaledi Subsystem and raise new questions about the process and timing of the fossil accumulations
Revision of thelodonts, acanthodians, conodonts, and the depositional environments in the Burgen outlier (Ludlow, Silurian) of Gotland, Sweden
No full textLudfordian strata exposed in the Burgen outlier in eastern Gotland, Sweden record a time of initial faunal recovery after a global environmental perturbation manifested in the Ludfordian Carbon Isotope Excursion (LCIE). Vertebrate microfossils in the collection of the late Lennart Jeppsson, hosted at the Swedish Museum of Natural History, hold the key to reconstruct the dynamics of faunal immigration and diversification during the decline of the LCIE, but the stratigraphic relationships of the strata have been debated. Historically, they had been placed in the Burgsvik Formation, which included the Burgsvik Sandstone and the Burgsvik Oolite members. We revise the fauna in the Jeppsson collection and characterize key outcrops of Burgen and Kapellet. The former Burgsvik Oolite Member is here revised as the Burgen Oolite Formation. In the Burgenoutlier, back-shoal facies of this formation are represented and their position in the Ozarkodina snajdri Biozone is supported. The shallow-marine position compared to the coeval strata in southern Gotland isreflected in the higher δ13C carb values, reaching +9.2‰. The back-shoal succession includes high-diversity metazoan reefs, which indicate a complete recovery of the carbonate producers as the LCIE declined. The impoverishment of conodonts associated with the LCIE in southern Gotland might be a product of facies preferences, as the diverse environments in the outlier yielded all 21 species known from the formation. Fish diversity also returned to normal levels as the LCIE declined, with a minimum of nine species. In line with previous reports, thelodont scales appear to dominate samples from the Burgen outlier
CarniFOSS: A database of the body mass of fossil carnivores
No full textMotivation Body mass is one of the most important determinants of animal ecology. Unlike other important traits it is also readily inferable from fossils and it is therefore one of the only traits that can be directly analysed and compared between fossil and contemporary communities. Despite this, no comprehensive database of the body mass of larger clades of extinct species exists. Analysis of fossils has therefore been restricted to small clades or to smaller, potentially biased, subsets of species. We here describe CarniFoss, an open-access database of body masses of all 1,322 extinct species of non-pinniped Carnivoramorpha and two related extinct groups of carnivorous mammals, Hyaenodonta and Oxyaenidae. Main types of variables contained We gathered lengths of teeth of fossil and extant species and body mass for extant species and a few of the best-known fossil species. Following this we estimated body mass for all species through phylogenetic imputation. Spatial location and grain Global, terrestrial. Time period and grain We collected data on all known species within the focal groups. The known species all lived in the Palaeogene, Neogene or Quaternary (i.e., the last 66 Myr). Major taxa and level of measurement We searched for data on reported tooth size of all described species of Carnivoramorpha (excluding pinnipeds) and selected extinct related groups (Hyaenodonta and Oxyaenidae). We combined this with measured body mass for all extant species and inferred body mass based on long-bones for selected extinct species, as well as a species-level phylogeny including all extant and extinct species in the group, and inferred the body mass for all species using phylogenetic imputation. Software format Data are provided as a series of .csv files, with all metadata in a separate PDF file
Genomic insights into the conservation status of the world's last remaining Sumatran rhinoceros populations
No full textMiniSCANS-II: Aerial survey for harbour porpoises in the western Baltic Sea, Belt Sea, the Sound and Kattegat in 2020 : Joint survey by Denmark, Germany and Sweden. Final report to Danish Environmental Protection Agency, German Federal Agency for Nature Conservation and Swedish Agency for Marine and Water Management.
No full textThe Marine Strategy Framework Directive (MSFD) (Directive 2008/56/EC) emphasises the need for cross-border monitoring of wide-ranging species, such as the harbour porpoise (Phocoena phocoena), the most abundant cetacean species occurring year-round in the Baltic Sea. In June and July 2020, Germany, Denmark, and Sweden conducted a dedicated large-scale aerial survey (called MiniSCANS-II) for harbour porpoises in the management area of the Belt Sea population, i.e., between an east-west line between Denmark and Sweden at 56.95°N in the Kattegat Sea, and a north-south line between Sweden and Germany at 13.5°E in the southern Baltic Sea. This survey followed line-transect distance sampling methodology according to the SCANS protocol to derive an unbiased absolute abundance estimate. With a realised effort of 4,533 km in nine strata, the observers recorded a total of 202 sightings (251 individuals, of these 16 were calves). The large majority of survey effort (91.2%) was conducted in either good or moderate sighting conditions. The abundance of the Belt Sea population was estimated to be 17,301 harbour porpoises (95% CI = 11,695-25,688; CV = 0.20), with an average density of 0.41 individuals/km² (95% CI = 0.28-0.61). This is the lowest abundance estimate since the first (SCANS) survey was conducted in 1994. However, the variance (especially of the earlier abundance estimates) is high, and a dedicated trend analysis needs to be conducted to determine if there has been a decline in the population abundance over time. The results should raise some concern about the status of the population and emphasise the importance of repeated surveys in the near future to increase the time series of robust abundance estimates available. Such time series are essential for monitoring the progress of the population towards achieving favourable conservation status under the Habitats Directive and good environmental status (GES) as demanded by the MSFD
Early flowers of primuloid Ericales from the Late Cretaceous of Portugal and their ecological and phytogeographic implications
No full textA distinctive feature of the major eudicot diversification that occurred through the Late Cretaceous is the unequivocal presence of Cornales and diverse Ericales. Here we describe well-preserved fossil flowers from the Mira locality in western Portugal, of Campanian-Maastrichtian age, that we assign to a new extinct genus of Ericales with two new species; Miranthus elegans gen. et sp. nov. and Miranthus kvacekii sp. nov. The fossil flowers are pedicellate, structurally bisexual, actinomorphic, pentamerous and isomerous, with five narrowly triangular persistent calyx lobes, a five-lobed corolla, five antepetalous stamens, five staminodes alternating with the petals and a semi-inferior, unilocular ovary. The ovary consists of five carpels and has a raised nectariferous ring with stomata-like openings above the insertion of the perianth, and a long five-angled style. A key feature, which confirms a relationship with Primulaceae s. l., is the free, central dome-shaped placenta that bears numerous, densely spaced ovules. The ovary matures into a capsule containing many, minute, reticulate seeds. Flowers of Miranthus are especially similar to those of extant Samolus, a genus of about twelve species that is sister group to other genera of subfamily Theophrastoideae and that has a disjunct distribution mainly in the Southern Hemisphere. Miranthus also appears to have grown in environments influenced by marine conditions, an ecological preference also seen in Samolus. Miranthus expands the diversity of Ericales known from the Late Cretaceous, and together with previously described fossils provides further evidence that the diversification of Ericales was already underway by the Campanian-Maastrichtian stages of the Late Cretaceous
Distribution and correlation of Sabellidites cambriensis (Annelida?) in the basal Cambrian on Baltica
No full textSabellidites cambriensis is a tubular non-mineralized metazoan that appears as compressed ribbon-shaped imprints with transverse wrinkling, thick walls and an even tube diameter of up to 3 mm. The distribution of Sabellidites is investigated in three Ediacaran–Cambrian sections on the Digermulen Peninsula in Arctic Norway, spanning the Manndrapselva Member of the Stáhpogieddi Formation and the lower member of the Breidvika Formation. Here, the Ediacaran–Cambrian boundary is located in the lower part of the upper parasequence (third cycle) of the Manndrapselva Member. Specimens of Sabellidites are rare but consistently present close to the lowest level of Treptichnus pedum and upsection, whereas the taxon is common and abundant in the lower part of the lower member of the Breidvika Formation, with an upper record at c. 55 m above the base. The range is comparable with that of the GSSP section in Newfoundland, Canada, establishing Sabellidites as an index fossil for the lowermost Cambrian. In the Manndrapselva Member, Sabellidites co-occurs with the acritarch Granomarginata, indicative of the lowermost Cambrian Granomarginata Zone, whereas in the Breidvika Formation it co-occurs with Asteridium. Sabellidites is widely distributed in Baltica, through the Rovnian and Lontovan regional stages but confined to the Fortunian global stage. In its lower range, Sabellidites is associated with a Treptichnus pedum trace fossil association and a depauperate leiosphaerid acritarch assemblage, followed by a Granomarginata assemblage. In its upper range, Sabellidites co-occurs with acritarchs of the Asteridium–Comasphaeridium Zone and the tubular foraminiferan Platysolenites. In Baltica, Sabellidites is a useful index fossil.The Digermulen Early Life Research Group acknowledges funding to Anette E. S. Högström from the Norwegian Research Council (NRC, project number 231103). Travel support was given to Frida Hybertsen by the Department of Earth Sciences, Palaeobiology, Uppsala University. T. P. & S. J. acknowledge funding from ‘Ministerio de Economía. Industria y Competitividad’ grant CGL 2017-87631-P.To view supplementary material for this article, please visit https://doi.org/10.1017/S0016756821001187</p
