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  • 101.
    Qu, Qingming
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi.
    Sanchez, Sophie
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Zhu, Min
    Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences.
    Blom, Henning
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Tafforeau, Paul
    European Synchrotron Radiation Facility.
    Ahlberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    The origin of novel features by changes in developmental mechanisms: a 3D virtual paleohistology study on polyodontode scales of primitive osteichthyans2015Manuskript (preprint) (Övrigt vetenskapligt)
  • 102.
    Qvarnström, Martin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Ahlberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Niedzwiedzki, Grzegorz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Tyrannosaurid-like osteophagy by a Triassic archosaur2019Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, artikel-id 925Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Here we present evidence for osteophagy in the Late Triassic archosaur Smok wawelski Niedzwiedzki, Sulej and Dzik, 2012, a large theropod-like predator from Poland. Ten medium to large-sized coprolites are matched, by their dimensions and by association with body fossils and footprints, to S. wawelski. The coprolites contain fragments of large serrated teeth as well as up to 50 percent by volume of bone fragments, with distinct fragmentation and angularity, from several prey taxa. This suggests pronounced osteophagy. Further evidence for bone-crushing behaviour is provided by isolated worn teeth, bone-rich regurgitalites (fossil regurgitates) and numerous examples of crushed or bite-marked dicynodont bones, all collected from the same bone-bearing beds in the Lipie Slaskie clay-pit. Several of the anatomical characters related to osteophagy, such as a massive head and robust body, seem to be shared by S. wawelski and the tyrannosaurids, despite their wide phylogenetic separation. These large predators thus provide evidence of convergence driven by similar feeding ecology at the beginning and end of the age of dinosaurs.

  • 103.
    Qvarnström, Martin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Elgh, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi.
    Owocki, Krzysztof
    Polish Acad Sci, Inst Paleobiol, Warsaw, Poland.
    Ahlberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Niedzwiedzki, Grzegorz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Filter feeding in Late Jurassic pterosaurs supported by coprolite contents2019Ingår i: PeerJ, ISSN 2167-8359, E-ISSN 2167-8359, Vol. 7, artikel-id e7375Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Diets of pterosaurs have mainly been inferred from indirect evidence such as comparative anatomy, associations of co-occurring fossils, and functional morphology. Gut contents are rare, and until now there is only a single coprolite (fossil dropping), with unidentified inclusions, known. Here we describe three coprolites collected from a palaeosurface with numerous pterosaur tracks found in early Kimmeridgian (Hypselocyclum Zone) intertidal deposits of the Wierzbica Quarry, Poland. The specimens' morphology and association to the tracks suggest a pterosaur producer. Synchrotron scans reveal numerous small inclusions, with foraminifera making up the majority of the identifiable ones. Other small remains include shells/carapaces (of bivalves, ostracods, and other crustaceans/arthropods) and bristles (some possibly of polychaete worms). The high density of the small shelly inclusions suggest that they were not accidently ingested, but constituted an important food source for the pterosaur(s), perhaps together with unpreserved soft-bodied animals. The combined evidence from the tracks and coprolites suggest a filter-feeding ctenochasmatid as the most likely tracemaker. If true, this significantly expands the bromalite record for this pterosaur group, which was previously only known from gastroliths. Moreover, this study also provides the first direct evidence of filter feeding in Jurassic pterosaurs and shows that they had a similar diet to the recent Chilean flamingo (Phoenicopterus chilensis).

  • 104.
    Qvarnström, Martin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Niedzwiedzki, Grzegorz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi.
    Tafforeau, Paul
    European Synchrotron Radiation Facility.
    Zigaite, Zivile
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi.
    Ahlberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi.
    3D – visualization of vertebrate coprolites through phase contrast synchrotron imaging unravel new aspects of paleoecological relations2017Ingår i: 77th Annual Meeting of the Society of Vertebrate Paleontology, Abstract book, 2017, s. 181-Konferensbidrag (Refereegranskat)
  • 105.
    Qvarnström, Martin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Niedzwiedzki, Grzegorz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Tafforeau, Paul
    European Synchrotron Radiat Facil, 71 Ave Martyrs,CS40200, F-38043 Grenoble, France..
    Zigaite, Zivile
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Ahlberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Synchrotron phase-contrast microtomography of coprolites generates novel palaeobiological data2017Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, artikel-id 2723Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Coprolites (fossil faeces) reveal clues to ancient trophic relations, and contain inclusions representing organisms that are rarely preserved elsewhere. However, much information is lost by classical techniques of investigation, which cannot find and image the inclusions in an adequate manner. We demonstrate that propagation phase-contrast synchrotron microtomography (PPC-SR mu CT) permits high-quality virtual 3D-reconstruction of coprolite inclusions, exemplified by two coprolites from the Upper Triassic locality Krasiejow, Poland; one of the coprolites contains delicate beetle remains, and the other one a partly articulated fish and fragments of bivalves.

  • 106.
    Qvarnström, Martin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Szrek, Piotr
    Natl Res Inst, Polish Geol Inst, Rakowiecka 4 St, PL-00075 Warsaw, Poland..
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Niedzwiedzki, Grzegorz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Non-marine palaeoenvironment associated to the earliest tetrapod tracks2018Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, artikel-id 1074Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Opinions differ on whether the evolution of tetrapods (limbed vertebrates) from lobe-finned fishes was directly linked to terrestrialization. The earliest known tetrapod fossils, from the Middle Devonian (approximately 390 million years old) of Zachelmie Quarry in Poland, are trackways made by limbs with digits; they document a direct environmental association and thus have the potential to help answer this question. However, the tetrapod identity of the tracks has recently been challenged, despite their well-preserved morphology, on account of their great age and supposedly shallow marine (intertidal or lagoonal) depositional environment. Here we present a new palaeoenvironmental interpretation of the track-bearing interval from Zachelmie, showing that it represents a succession of ephemeral lakes with a restricted and non-marine biota, rather than a marginal marine environment as originally thought. This context suggests that the trackmaker was capable of terrestrial locomotion, consistent with the appendage morphology recorded by the footprints, and thus provides additional support for a tetrapod identification.

  • 107.
    Qvarnström, Martin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Vikberg Wernström, Joel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi.
    Piechowski, Rafal
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland;Univ Warsaw, Dept Palaeobiol & Evolut, Fac Biol, Biol & Chem Res Ctr, Zwirki & Wigury 101, PL-02089 Warsaw, Poland.
    Talanda, Mateusz
    Univ Warsaw, Dept Palaeobiol & Evolut, Fac Biol, Biol & Chem Res Ctr, Zwirki & Wigury 101, PL-02089 Warsaw, Poland.
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Niedzwiedzki, Grzegorz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Beetle-bearing coprolites possibly reveal the diet of a Late Triassic dinosauriform2019Ingår i: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, nr 3, artikel-id 181042Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Diets of extinct animals can be difficult to analyse if no direct evidence, such as gut contents, is preserved in association with body fossils. Inclusions from coprolites (fossil faeces), however, may also reflect the diet of the host animal and become especially informative if the coprolite producer link can be established. Here we describe, based on propagation phase-contrast synchrotron microtomography (PPC-SRμCT), the contents of five morphologically similar coprolites collected from two fossil-bearing intervals from the highly fossiliferous Upper Triassic locality at Krasiejow in Silesia, Poland. Beetle remains, mostly elytra, and unidentified exoskeleton fragments of arthropods are the most conspicuous inclusions found in the coprolites. The abundance of these inclusions suggests that the coprolite producer deliberately targeted beetles and similar small terrestrial invertebrates as prey, but the relatively large size of the coprolites shows that it was not itself a small animal. The best candidate from the body fossil record of the locality is the dinosauriform Silesaurus opolensis Dzik, 2003, which had an anatomy in several ways similar to those of bird-like neotheropod dinosaurs and modern birds. We hypothesize that the beak-like jaws of S. opolensis were used to efficiently peck small insects off the ground, a feeding behaviour analogous to some extant birds.

  • 108. Robinson, Jamie
    et al.
    Ahlberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för fysiologi och utvecklingsbiologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för fysiologi och utvecklingsbiologi, Evolutionär organismbiologi. Evolutionär organismbiologi.
    Koentges, Georgy
    The braincase and middle ear region of Dendrerpeton acadianum (Tetrapoda: Temnospondyli).2005Ingår i: Zoological Journal of the Linnean Society, ISSN 0024-4082, Vol. 143, nr 4, s. 577-597Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dendrerpeton acadianum from the Westphalian A (Upper Carboniferous) of Joggins, Nova Scotia, is a phylogenetically and chronologically early temnospondyl. Its external cranial anatomy has been used previously to suggest the presence of a tympanic membrane, and thus of an ear adapted to the perception of airborne sound. However, supporting evidence provided by stapedial and braincase morphology has so far been lacking. The braincase and middle ear region have remained almost wholly unknown. CT scanning and 3-D computer reconstruction of BMNH R.436 have been used to shed light on these important areas. Both stapes prove to be present in the specimen; the right stapes is distorted, but the left stapes lies inside the cranial cavity and is perfectly preserved. The latter resembles the stapes of the relatively few other temnospondyls in which the bone has been described and is most similar to that of Doleserpeton. The morphology and orientation of the stapes provide strong evidence for the presence of an ear adapted to the perception of airborne sound, with similarities to the extant anuran condition. The reconstructed braincase shows a high degree of similarity to that of other adequately known temnospondyls. This gives supporting evidence that D. acadianum is correctly placed in the temnospondyl phylogeny and thus demonstrates one of the earliest hearing systems adapted to the perception of airborne sound that can be homologized with the extant anuran condition.  © 2005 The Trustees of the Natural History Museum, Zoological Journal of the Linnean Society, 2005, 143, 577-597.

  • 109.
    Ruta, Marcello
    et al.
    Univ Lincoln, Sch Life Sci, Joseph Banks Labs, Green Lane, Lincoln LN6 7DL, England.
    Ahlberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Smithson, Timothy R.
    Univ Museum Zool, Downing St, Cambridge CB2 3EJ, England.
    Fossils, function and phylogeny: Papers on early vertebrate evolution in honour of Professor Jennifer A. Clack - Introduction2019Ingår i: Earth and environmental science transactions of the Royal Society of Edinburgh, ISSN 1755-6910, E-ISSN 1755-6929, Vol. 109, nr 1-2, s. 1-14Artikel i tidskrift (Refereegranskat)
  • 110.
    Ryll, Bettina
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Sanchez, Sophie
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Haitina, Tatjana
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Tafforeau, Paul
    Ahlberg, Per Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    The genome of Callorhinchus and the fossil record: a new perspective on SCPP gene evolution in gnathostomes2014Ingår i: Evolution & Development, ISSN 1520-541X, E-ISSN 1525-142X, Vol. 16, nr 3, s. 123-124Artikel i tidskrift (Övrigt vetenskapligt)
  • 111.
    Sanchez, Sophie
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Trinajstic, Katherine M.
    Mirone, Alessandro
    Tafforeau, Paul
    Three-Dimensional Synchrotron Virtual Paleohistology: A New Insight into the World of Fossil Bone Microstructures2012Ingår i: Microscopy and Microanalysis, ISSN 1431-9276, E-ISSN 1435-8115, Vol. 18, nr 5, s. 1095-1105Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The recent developments of phase-contrast synchrotron imaging techniques have been of great interest for paleontologists, providing three-dimensional (3D) tomographic images of anatomical structures, thereby leading to new paleobiological insights and the discovery of new species. However, until now, it has not been used on features smaller than 57 mu m voxel size in fossil bones. Because much information is contained within the 3D histological architecture of bone, including an ontogenetic record, crucial for understanding the paleobiology of fossil species, the application of phase-contrast synchrotron tomography to bone at higher resolutions is potentially of great interest. Here we use this technique to provide new 3D insights into the submicron-scale histology of fossil and recent bones, based on the development of new pink-beam configurations, data acquisition strategies, and improved processing tools. Not only do the scans reveal by nondestructive means all of the major features of the histology at a resolution comparable to that of optical microscopy, they provide 3D information that cannot be obtained by any other method.

  • 112.
    Sanchez, Sophie
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Dupret, Vincent
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Ryll, Bettina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Trinajstic, Kate
    Curtin University, Western Australia.
    Wretman, Lovisa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Zylberberg, Louise
    Université Pierre et Marie Curie, UPMC, Paris, France.
    Tafforeau, Paul
    European Synchrotron Radiation Facility, Grenoble, France.
    Ahlberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Fossil bone histology revealed in 3D thanks to the synchrotron light: palaeobiological implications2011Konferensbidrag (Refereegranskat)
  • 113.
    Sanchez, Sophie
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Dupret, Vincent
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Ryll, Bettina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Trinajstic, Kate
    Curti University, Western Australia.
    Wretman, Lovisa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Zylberberg, Louise
    Université Pierre et Marie Curie, UPMC, Paris, France.
    Tafforeau, Paul
    European Synchrotron Radiation Facility, Grenoble, France.
    Ahlberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Synchrotron virtual palaeohistology: a new tool for studying the evolution of bone microstructures in 3D2011Konferensbidrag (Refereegranskat)
  • 114.
    Sanchez, Sophie
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Dupret, Vincent
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi.
    Tafforeau, Paul
    Trinajstic, Katherine M.
    Ryll, Bettina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Gouttenoire, Pierre-Jean
    Wretman, Lovisa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Zylberberg, Louise
    Peyrin, Francoise
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    3D Microstructural Architecture of Muscle Attachments in Extant and Fossil Vertebrates Revealed by Synchrotron Microtomography2013Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, nr 2, s. e56992-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Firm attachments binding muscles to skeleton are crucial mechanical components of the vertebrate body. These attachments (entheses) are complex three-dimensional structures, containing distinctive arrangements of cells and fibre systems embedded in the bone, which can be modified during ontogeny. Until recently it has only been possible to obtain 2D surface and thin section images of entheses, leaving their 3D histology largely unstudied except by extrapolation from 2D data. Entheses are frequently preserved in fossil bones, but sectioning is inappropriate for rare or unique fossil material.

    Methodology/Principal Findings: Here we present the first non-destructive 3D investigation, by propagation phase contrast synchrotron microtomography (PPC-SR mu CT), of enthesis histology in extant and fossil vertebrates. We are able to identify entheses in the humerus of the salamander Desmognathus from the organization of bone-cell lacunae and extrinsic fibres. Statistical analysis of the lacunae differentiates types of attachments, and the orientation of the fibres, reflect the approximate alignment of the muscle. Similar histological structures, including ontogenetically related pattern changes, are perfectly preserved in two 380 million year old fossil vertebrates, the placoderm Compagopiscis croucheri and the sarcopterygian fish Eusthenopteron foordi.

    Conclusions/Significance: We are able to determine the position of entheses in fossil vertebrates, the approximate orientation of the attached muscles, and aspects of their ontogenetic histories, from PPC-SRmCT data. Sub-micron microtomography thus provides a powerful tool for studying the structure, development, evolution and palaeobiology of muscle attachments.

  • 115.
    Sanchez, Sophie
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Tafforeau, P.
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    The humerus of Eusthenopteron: a puzzling organization presaging the establishment of tetrapod limb bone marrow2014Ingår i: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 281, nr 1782, s. 20140299-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Because of its close relationship to tetrapods, Eusthenopteron is an important taxon for understanding the establishment of the tetrapod body plan. Notably, it is one of the earliest sarcopterygians in which the humerus of the pectoral fin skeleton is preserved. The microanatomical and histological organization of this humerus provides important data for understanding the evolutionary steps that built up the distinctive architecture of tetrapod limb bones. Previous histological studies showed that Eusthenopteron's long-bone organization was established through typical tetrapod ossification modalities. Based on a threedimensional reconstruction of the inner microstructure of Eusthenopteron's humerus, obtained from propagation phase-contrast X-ray synchrotron microtomography, we are now able to show that, despite ossification mechanisms and growth patterns similar to those of tetrapods, it also retains plesiomorphic characters such as a large medullary cavity, partly resulting from the perichondral ossification around a large cartilaginous bud as in actinopterygians. It also exhibits a distinctive tubular organization of bone-marrow processes. The connection between these processes and epiphyseal structures highlights their close functional relationship, suggesting that either bone marrow played a crucial role in the long-bone elongation processes or that trabecular bone resulting from the erosion of hypertrophied cartilage created a microenvironment for haematopoietic stem cell niches.

  • 116.
    Szrek, Piotr
    et al.
    Polish Geol Inst, Natl Res Inst, Rakowiecka 4 St, PL-00075 Warsaw, Poland. Polish Geol Inst, Natl Res Inst, Holy Cross Mt Branch, Zgoda 21 St, PL-00075 Kielce, Poland..
    Salwa, Sylwester
    Holy Cross Mountains Branch of the Polish Geological Institute—National Research Institute, Zgoda 21 Street, 00-075 Kielce, Poland.
    Niedzwiedzki, Grzegorz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Dec, Marek
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland..
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Uchman, Alfred
    Jagiellonian Univ, Inst Geol Sci, Oleandry 2a, PL-30063 Krakow, Poland..
    A glimpse of a fish face: An exceptional fish feeding trace fossil from the Lower Devonian of the Holy Cross Mountains, Poland2016Ingår i: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 454, s. 113-124Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An exceptionally well-preserved assemblage of numerous invertebrate and vertebrate trace fossils is described from the Lower Devonian of the Holy Cross Mountains, southern Poland. Two trace-bearing horizons occur in the shallow-marine sequence that is exposed in a small outcrop near Ujazd village. One of the trace fossils is preserved as a bilobate, generally elliptical, epichnial pit is described as Osculichnus tarnowskae isp. nov. and interpreted as a unique example of praedichnia. Neoichnologic experiments and observations indicate that the ichnogenus Osculichnus was produced by feeding fish. The fish producing O. tarnowskae probably hunted bivalves, polychaetes and arthropods, which are represented by invertebrate trace fossils in the same horizons. The overall shape and morphological details of O. tarnowskae suggest that it was made by a lungfish broadly similar to Dipnorhynchus. The trace provides the first direct evidence for Devonian lungfish feeding behaviour, as well as the first record of three-dimensional soft-tissue morphology of the snout area of an Emsian representative of this group. The trace fossils from Ujazd provide new insight into the palaeoecology and taphonomy of the Lower Devonian of the Holy Cross Mountains.

  • 117. Trinajstic, Kate
    et al.
    Sanchez, Sophie
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Dupret, Vincent
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Tafforeau, Paul
    Long, John
    Young, Gavin
    Senden, Tim
    Boisvert, Catherine
    Power, Nicola
    Ahlberg, Per Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Fossil Musculature of the Most Primitive Jawed Vertebrates2013Ingår i: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 341, nr 6142, s. 160-164Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The transition from jawless to jawed vertebrates (gnathostomes) resulted in the reconfiguration of the muscles and skeleton of the head, including the creation of a separate shoulder girdle with distinct neck muscles. We describe here the only known examples of preserved musculature from placoderms (extinct armored fishes), the phylogenetically most basal jawed vertebrates. Placoderms possess a regionalized muscular anatomy that differs radically from the musculature of extant sharks, which is often viewed as primitive for gnathostomes. The placoderm data suggest that neck musculature evolved together with a dermal joint between skull and shoulder girdle, not as part of a broadly flexible neck as in sharks, and that transverse abdominal muscles are an innovation of gnathostomes rather than of tetrapods.

  • 118.
    Vaskaninova, Valeria
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi. Charles Univ Prague, Fac Sci, Inst Geol & Palaeontol, Prague, Czech Republic..
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Unique diversity of acanthothoracid placoderms (basal jawed vertebrates) in the Early Devonian of the Prague Basin, Czech Republic: A new look at Radotina and Holopetalichthys2017Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, nr 4, artikel-id e0174794Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The taxonomy of Early Devonian placoderm material from the Lochkovian and Pragian of the Prague basin, previously attributed to the genera Radotina and Holopetalichthys, is revised. The Pragian species Radotina tesselata Gross 1958 shares detailed similarities with the holotype of the Lochkovian Radotina kosorensis Gross 1950, which is also the holotype of the genus; the assignation of both species to Radotina is supported. However, the Lochkovian material previously attributed to Radotina kosorensis also contains two unrecognised taxa, distinguishable from Radotina at the generic level: these are here named Tlamaspis and Sudaspis. The disputed genus Holopetalichthys, synonymised with Radotina by some previous authors, is shown to be valid. Furthermore, whereas Radotina, Tlamaspis and Sudaspis can all be assigned to the group Acanthothoracii, on the basis of several features including possession of a projecting prenasal region of the endocranium, Holopetalichthys lacks such a region and is probably not an acanthothoracid. Skull roof patterns and other aspects of morphology vary greatly between these taxa. Radotina has a substantially tesselated skull roof, whereas the skull roofs of Tlamaspis and Holopetalichthys appear to lack tesserae altogether. Tlamaspis has an extremely elongated facial region and appears to lack a premedian plate. Sudaspis has a long prenasal region, but unlike Tlamaspis the postnasal face is not elongated. Past descriptions of the braincase of ' Radotina' and the skull roofs of ' Radotina' and ' Holopetalichthys' incorporate data from more than one taxon, giving rise to spurious characterisations including an apparently extreme degree of skull roof variability. These descriptions should all be disregarded.

  • 119.
    Zaton, Michal
    et al.
    Univ Silesia, Fac Earth Sci, Bedzinska 60, PL-41200 Sosnowiec, Poland..
    Broda, Krzysztof
    Univ Silesia, Fac Earth Sci, Bedzinska 60, PL-41200 Sosnowiec, Poland..
    Qvarnström, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Niedzwiedzki, Grzegorz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Ahlberg, Per Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    The first direct evidence of a Late Devonian coelacanth fish feeding on conodont animals2017Ingår i: The Science of Nature: Naturwissenschaften, ISSN 0028-1042, E-ISSN 1432-1904, Vol. 104, nr 3-4, artikel-id 26Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We describe the first known occurrence of a Devonian coelacanth specimen from the lower Famennian of the Holy Cross Mountains, Poland, with a conodont element preserved in its digestive tract. A small spiral and phosphatic coprolite (fossil excrement) containing numerous conodont elements and other unrecognized remains was also found in the same deposits. The coprolite is tentatively attributed to the coelacanth. Although it is unclear whether the Late Devonian coelacanth from Poland was an active predator or a scavenger, these finds provide the first direct evidence of feeding on conodont animals by early coelacanth fish, and one of the few evidences of feeding on these animals known to date. It also expands our knowledge about the diet and trophic relations between the Paleozoic marine animals in general.

  • 120.
    Zhu, Min
    et al.
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China.;Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China..
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Pan, Zhaohui
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China.;Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China..
    Zhu, Youan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Qiao, Tuo
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    Zhao, Wenjin
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    Jia, Liantao
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    Lu, Jing
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    A Silurian maxillate placoderm illuminates jaw evolution2016Ingår i: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 354, nr 6310, s. 334-336Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The discovery of Entelognathus revealed the presence of maxilla, premaxilla, and dentary, supposedly diagnostic osteichthyan bones, in a Silurian placoderm. However, the relationship between these marginal jaw bones and the gnathal plates of conventional placoderms, thought to represent the inner dental arcade, remains uncertain. Here we report a second Silurian maxillate placoderm, which bridges the gnathal and maxillate conditions. We propose that the maxilla, premaxilla, and dentary are homologous to the gnathal plates of placoderms and that all belong to the same dental arcade. The gnathal-maxillate transformation occurred concurrently in upper and lower jaws, predating the addition of infradentary bones to the lower jaw.

  • 121.
    Zhu, Min
    et al.
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China.;Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China..
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Zhao, Wen-Jin
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China.;Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China..
    Jia, Lian-Tao
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    A Devonian tetrapod-like fish reveals substantial parallelism in stem tetrapod evolution2017Ingår i: Nature Ecology & Evolution, E-ISSN 2397-334X, Vol. 1, nr 10, s. 1470-1476Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The fossils assigned to the tetrapod stem group document the evolution of terrestrial vertebrates from lobe-finned fishes. During the past 18 years the phylogenetic structure of this stem group has remained remarkably stable, even when accommodating new discoveries such as the earliest known stem tetrapod Tungsenia and the elpistostegid (fish-tetrapod intermediate) Tiktaalik. Here we present a large lobe-finned fish from the Late Devonian period of China that disrupts this stability. It combines characteristics of rhizodont fishes (supposedly a basal branch in the stem group, distant from tetrapods) with derived elpistostegid-like and tetrapod-like characters. This melange of characters may reflect either detailed convergence between rhizodonts and elpistostegids plus tetrapods, under a phylogenetic scenario deduced from Bayesian inference analysis, or a previously unrecognized close relationship between these groups, as supported by maximum parsimony analysis. In either case, the overall result reveals a substantial increase in homoplasy in the tetrapod stem group. It also suggest that ecological diversity and biogeographical provinciality in the tetrapod stem group have been underestimated.

  • 122. Zhu, Min
    et al.
    Yu, Xiaobo
    Ahlberg, Per Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Choo, Brian
    Lu, Jing
    Qiao, Tuo
    Qu, Qingming
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Zhao, Wenjin
    Jia, Liantao
    Blom, Henning
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Zhu, You'an
    A Silurian placoderm with osteichthyan-like marginal jaw bones2013Ingår i: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 502, nr 7470, s. 188-+Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The gnathostome (jawed vertebrate) crown group comprises two extant clades with contrasting character complements. Notably, Chondrichthyes (cartilaginous fish) lack the large dermal bones that characterize Osteichthyes (bony fish and tetrapods). The polarities of these differences, and the morphology of the last common ancestor of crown gnathostomes, are the subject of continuing debate. Here we describe a three-dimensionally preserved 419-million-year-old placoderm fish from the Silurian of China that represents the first stem gnathostome with dermal marginal jaw bones (premaxilla, maxilla and dentary), features previously restricted to Osteichthyes. A phylogenetic analysis places the new form near the top of the gnathostome stem group but does not fully resolve its relationships to other placoderms. The analysis also assigns all acanthodians to the chondrichthyan stem group. These results suggest that the last common ancestor of Chondrichthyes and Osteichthyes had a macromeric dermal skeleton, and provide a new framework for studying crown gnathostome divergence.

  • 123.
    Zigaite, Zivile
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Fadel, Alexandre
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Blom, Henning
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Perez-Huerta, Alberto
    Jeffries, Teresa
    Maerss, Tiiu
    Ahlberg, Per Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Rare earth elements (REEs) in vertebrate microremains from the upper Pridoli Ohesaare beds of Saaremaa Island, Estonia: geochemical clues to palaeoenvironment2015Ingår i: Estonian journal of earth sciences, ISSN 1736-4728, E-ISSN 1736-7557, Vol. 64, nr 1, s. 115-120Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rare earth element (REE) compositions of Nostolepis sp. scales, spines, plates and tesserae from Ohesaare bone beds were measured by in situ microsampling using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The obtained REE concentrations, normalized to Post-Archean Australian Shale concentrations, were evaluated using basic geochemical calculations and quantifications. The REE compositions were nearly identical across all the morphotypes and histologies of Nostolepis microremains, showing flat REE patterns with slight depletion in heavy REEs. There was no visible enrichment in middle REEs, indicating good geochemical preservation of bioapatite and absence of any pronounced fractionated REE incorporation during later stages of diagenesis. The shale-normalized (La/Yb)(SN) and (La/Sm)(SN) REE ratio compilations indicated adsorption as the dominating REE uptake mechanism across all datapoints. The absence of well-defmed Ce anomaly suggested oxic palaeoseawater conditions, which agrees with the existing interpretations of the Ohesaare sequence as high-energy shoal and regressive open ocean sedimentary environments.

  • 124.
    Zigaite, Zivile
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Fadel, Alexandre
    Universite Lille-1.
    Blom, Henning
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Perez-Huerta, Alberto
    University of Alabama.
    Jeffries, Teressa
    Natural History Museum London.
    Ahlberg, Per Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Rare earth and trace elements in fossil vertebrate biomineral as indicators of palaeoecology and palaeoenvironment2014Ingår i: 4th Annual Meeting of IGCP 591 The Early to Middle Paleozoic Revolution Estonia, 10-19 June 2014Abstracts & Field Guide, 2014, s. 105-105Konferensbidrag (Refereegranskat)
  • 125.
    Zigaite, Zivile
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi.
    Fadel, Alexandre
    Universite Lille-1.
    Perez-Huerta, Alberto
    University of Alabama.
    Jeffries, Teresa
    London Natural History Museum.
    Blom, Henning
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi.
    Ahlberg, Per Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi.
    Rare earth and trace elements of fossil bioapatite as palaeoenvironmental proxies: the Lower Devonian of the Andree Land, Svalbard2014Ingår i: Résumés dela 24eRéunion des Sciences de la Terre Abstracts, 2014, s. 481-481Konferensbidrag (Refereegranskat)
  • 126.
    Zigaite, Zivile
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Fadel, Alexandre
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi. Univ Lille 1, CNRS UMR8217, Lab Geosyst, F-59655 Villeneuve Dascq, France.
    Perez-Huerta, Alberto
    Univ Alabama, Dept Geol Sci, 2018 Bevill Bldg, Tuscaloosa, AL 35487 USA.
    Jeffries, Teresa
    Dept Earth Sci, Nat Hist Museum, Cromwell Rd, London SW7 5BD, England.
    Goujet, Daniel
    Museum Natl Hist Nat, Dept Hist Terre, Lab Paleontol, UMR CNRS 7207, 57 Rue Cuvier, F-75231 Paris 5, France.
    Ahlberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Palaeoenvironments revealed by rare-earth element systematics in vertebrate bioapatite from the Lower Devonian of Svalbard2016Ingår i: Canadian journal of earth sciences (Print), ISSN 0008-4077, E-ISSN 1480-3313, Vol. 53, nr 8, s. 788-794Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In situ rare-earth element (REE) compositions have been measured in early vertebrate microremains from the Lower Devonian basin of Andree Land (Svalbard), with the aim of obtaining information about their early depositional environment and potential reworking. Vertebrate microremains with different histology were used for the analyses, sourced from two different localities of marginal marine to freshwater sediments from geographically distant parts of the Grey Hoek Formation (Skamdalen and Tavlefjellet members). We selected thelodont and undescribed ? chondrichthyan scales, which allowed us to define potential taxonomic, histological, and taphonomic variables of the REE uptake. Results showed REE concentrations to be relatively uniform within the scales of each taxon, but apparent discrepancies were visible between the studied localities and separate taxa. The compilation of REE abundance patterns as well as REE ratios have revealed that thelodont and ? chondrichthyan originating from the same locality must have had different burial and early diagenetic histories. The shapes of the REE profiles, together with the presence and absence of the Eu and Ce anomalies, equally suggested different depositional and diagenetic environments for these two sympatric taxa resulting from either stratigraphical or long-distance reworking. The REE concentrations appear to have visible differences between separate dental tissues, particularly between enameloid and dentine of thelodonts, emphasizing the importance of in situ measurements in microfossil biomineral geochemistry.

  • 127.
    Zigaite, Zivile
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Pérez-Huerta, Alberto
    University of Alabama.
    Fadel, Alexander
    University of Lille-1.
    Jeffries, Teresa
    London Natural History Museum.
    Blom, Henning
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi.
    Goujet, Daniel
    Muséum national d'histoire naturelle.
    Ahlberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi.
    Andrée Land of Spitsbergen:: Devonian vertebrate diversity and palaeoenvironments2018Konferensbidrag (Refereegranskat)
  • 128.
    Zigaite, Zivile
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Whitehouse, Martin
    Naturhistoriska Riksmuseet Stockholm.
    Joachimski, Michael M.
    University of Erlangen Nuremberg.
    Sansom, Ivan
    University of Birmingham.
    Ahlberg, Per Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Oxygen isotopes in modern and fossil ecosystems: model and case study overview2016Konferensbidrag (Övrigt vetenskapligt)
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