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Current third-party funded projects are supported by:

  • Austrian Science Fund (FWF)
  • Sharkproject Austria
  • Austrian Agency for International Cooperation in Education & Research (OeAD-GmbH)


Evolutionary Dynamics of Eocenen Antarctic Fishes

(FWF-Project P26465-B25)



Primary Investigator: Univ.-Prof. Dr. Jürgen Kriwet


Background

The Palaeogene was one of the most important time intervals in global climatic developments characterized, inter alia, by a late Eocene transition from the greenhouse world to icehouse conditions (ca. 49-34 Ma). The final cooling phase across the Eocene-Oligocene (E-O) boundary (ca. 33.7 Ma) resulted in the thermal isolation of Antarctica and the establishment of large Antarctic ice sheets. These climatic changes, which persisted into the earliest Oligocene resulted in major biotic turnovers in marine and terrestrial floras and faunas. Today’s Southern Ocean, which is delimited by the circum-Antarctic current (Antarctic Convergence) and the Antarctic continent, which is located within it are amongst the most remote and coldest places in the world and are both a key element in any model of Earth processes and climatic changes as well as a site of unique evolutionary traits related to the abiotic characters. The extant fish fauna within the Antarctic Convergence is striking in its low taxonomic diversity and high number of endemic taxa. The chondrichthyan fauna is extremely impoverished compared to the modern teleost fauna and this situation was similar in the Eocene.
The project aims at documenting and analysing the biotic effects of both short-term and long-term climate and palaeogeographic changes in Antarctica focusing on the taxonomic composition and diversity dynamics of Eocene Antarctic holocephalan and elasmobranchian fishes, which will serve as model organisms for evolutionary patterns in high-latitudes. Analysing originations, extinctions, diversity and diversification patterns and the palaeoecology of chondrichthyans in combination with extrinsic factors, which might influence evolutionary processes (e.g., climatic changes, palaeogeographic constellations) throughout the Eocene until the thermal and geographic isolation of Antarctica will not only provide deeper insights into adaptive and evolutionary patterns of high-latitude cartilaginous fishes but also into the development and probably the origin of the conspicuous modern-day Antarctic fish fauna with no resident holocephalans and sharks. Previous hypotheses stating, for instance, that there is a continuous diversity increase until the middle Eocene and that the absence of chondrichthyans in the uppermost Eocene of Antarctica is the result of the onset of the thermal isolation of the Antarctic continent will be tested with rigorous methodological approaches.

Locality and Material

The material that forms the basis of this project was assembled by an Argentine-Swedish field party as a joint project of the Instituto Antártico Argentino (IAA) and the Swedish Polar Secretary (SPFS) and is housed in the palaeozoological collections of the Swedish Museum of Natural History (NRM). This abundant new material of cartilaginous fishes from all stratigraphic levels of the La Meseta Fm. of Seymour Island (Antarctic Peninsula) was collected during three Antarctic summer campaigns (SWEDARP 2011-2013). Further field campaigns are planned for 2014 and 2015. The material was obtained by surface collecting and screen-washing of bulk samples. Currently, the NRM collection comprises > 3.500 specimens (isolated dental plates, teeth, placoid scales, fin spines, etc.). The significance of this new material is: (1) it represents the largest collection of cartilaginous fish remains from the Eocene of Antarctica up to now, (2) it includes abundant new material of hitherto incompletely known but also new taxa, (3) it contains the first chondrichthyan records from the upper most parts of the Antarctic Eocene and (4) it contains a highly diverse microvertebrate fauna including ample micro-teeth and placoid scales from different Eocene levels of Antarctica. This is the most complete collection of chondrichthyans from the Eocene of Antarctica in terms of number of specimens, taxonomic covering and stratigraphic distribution.

Goals:

The ultimate goal is to present a comprehensive study of cartilaginous fish assemblages from the Eocene of Antarctica including revisions of previously published records. Integrated goals of this project are to (1) establish the taxonomic / systematic composition and stratigraphic distribution of cartilaginous fishes for each Eocene stratigraphic unit (here TELMs) of Antarctica, (2) establish the quality of their fossil record, (3) analyse the faunal relationships (Beta Diversity) of Eocene Antarctic chondrichthyan compositions, (4) study the underlying evolutionary dynamics such as origination, diversification, diversity fluctuation and extinction patterns of fishes in high latitudes during the Eocene and (5) reconstruct ecological patterns of Eocene Antarctic chondrichthyans.

Team

  • Univ.-Prof. Dr. Jürgen Kriwet (PI) Read more
  • Mag. Andrea Engelbrecht (Predoctoral Researcher)
  • Iris Fuchs, BSc (Student Assistent)

Collaborations:


Research Projects:

Batchelor and master students (Palaeobiology, Zoology, Ecology) are welcome to conduct projects for their thesis within this project. Projects range from analytical studies employing rigorous mathematical approaches to analysing calcification patterns in skeletal elements of Antarctic fishes and taxonomic evaluations. As a Batcherlor or Masterstudent in the Vertebrate Palaeobiology Group, you will work in a very active and dynamic group on applied research projects.

For more information please contact:

Univ.-Prof. Dr. Jürgen Kriwet
Department of Palaeontology
University of Vienna
Geozentrum
UZA 2
Althanstrasse 14
1090 Vienna, Austria
Tel: ++43-1-4277 / 535 20
e-mail: juergen.kriwet@univie.ac.at


Publications

For PDFs visit https://www.researchgate.net/profile/Juergen_Kriwet

Technical Papers
  • Marramà, G., Engelbrecht, A., Carnevale, G. & Kriwet, J. in press. Eocene sand tiger sharks (Lamniformes, Odontaspididae) from the Bolca Konservat-Lagerstätte, Italy: Palaeobiology, palaeobiogeography and evolutionary significance. Historical Biology.
  • Marramà, G., Carnevale, G., Engelbrecht, A., Claeson, K.M., Zorzin, R., Fornasiero, M. & Kriwet, J. in review. A synoptic review of the Eocene (Ypresian) cartilaginous fishes (Chondrichthyes: Holocephali, Elasmobranchii) of the Bolca Konservat-Lagertätte, Italy. Paläontologische Zeitschrift.
  • Marramà, G., Claeson, K.M., Carnevale, C., Kriwet, J. submitted. Revision of Eocene electric rays (Torpediniformes, Batomorphii) from the Bolca Konservat-Lagerstätte, Italy, reveals the first fossil embryo in situ in batoids and provides new insights into the origin of trophic novelties in coral reef fishes. Journal of Systematic Palaeontology.
  • Engelbrecht, A., Mörs, T., Reguero, M. & Kriwet, J. submitted. submitted. Deep-water sharks (Squalomorphii) of the Eocene La Meseta Formation, Seymour Island, Antarctic Peninsula. Journal of South American Earth Sciences.
  • Engelbrecht, A., Mörs, T., Reguero, M. & Kriwet, J. in review. New carcharhiniform sharks (Chondrichthyes, Elasmobranchii) from the early to middle Eocene, of Seymour Island, Antarctic Peninsula. Journal of Vertebrate Paleontology.
  • Schwarzhans, W., Mörs, T., Engelbrecht, A., Reguero, M. & Kriwet, J. 2017. Before the freeze: Otoliths from the Eocene of Seymour Island, Antarctica, reveal dominance of gadiform fishes (Teleostei). Journal of Systematic Palaeontology 15:2, 147-170. Link to article
  • Engelbrecht, A., Mörs, T., Reguero, M. & Kriwet, J. 2017. A new sawshark, Pristiophorus laevis, from the Eocene of Antarctica with comments on Pristiophorus lanceolatus. Historical Biology 29: 841-853 Link to article
  • Engelbrecht, A., Mörs, T., Reguero, M. & Kriwet, J. 2016 (online first). Revision of Eocene Antarctic carpet sharks (Elasmobranchii, Orectolobiformes) from Seymour Island, Antarctic Peninsula. Journal of Systematic Palaeontology. Link to article
  • Kriwet, J., Engelbrecht, A., Mörs, T., Reguero, M. & Pfaff, C. 2016. Ultimate Eocene (Priabonian) chondrichthyans (Holocephali, Elasmobranchii) of Antarctica. Journal of Vertebrate Paleontology 36: e1160911 (19 pages).
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Ecological effects of competition on pycnodont fishes (Actinopterygii, Neopterygii, Pycnodontomorpha) and its possible role leading to their extinction

(FWF-Project P 29796-B29)



Primary Investigator: Univ.-Prof. Dr. Jürgen Kriwet


Background

Pycnodont fishes (Pycnodontomorpha) are a monophyletic and ecologically successful clade of extinct ray finned fishes with a fossil record spanning 175 million years from the Late Triassic to middle Eocene (Tintori 1981; Poyato-Ariza & Wenz 2002; Kriwet & Schmitz 2005). They are most commonly associated with shallow water marine habitats but are also found in association with freshwater and estuarine deposits (Longbottom 1984; Poyato-Ariza et al. 1998). A deep, rounded, and laterally compressed body, a frontal flexure of the skull in profile view, a more or less prognathous snout, and elongated dorsal and anal fins, forming together with the caudal fin an effective rudder characterize pycnodonts (Fig. 1). In their body shape they superficially resemble extant coral reef fishes like butterflyfishes (Chaetodontidae), doctorfishes (Acanthuridae), and triggerfishes (Balistidae). Distinctive characteristics of pycnodonts are their molariform teeth, which generally are arranged in well-defined rows on the unpaired vomer (upper jaw) and paired prearticulars (lower jaws) (Fig. 2). This dentition represents an adaptation to shelled prey. Their diversity is strikingly high, with over >600 nominal species in >45 genera of which many taxa are based on teeth and dentitions only (Kriwet, 2001a; 2005). The palaeobiogeography of these fishes suggests they originated in the Tethys Sea initially and then spread worldwide (Kriwet 2008; Martín-Abad & Poyato-Ariza 2013).
Traditionally considered an order, Pycnodontiformes (Poyato-Ariza & Wenz 2002), they are now accepted to represent a superorder, Pycnodontomorpha, which was considered as a possible sister group candidate to Teleostei (Nursall 2010). However, a more recent analysis by Poyato-Ariza (2015) identified pycnodonts to be the sister group to Halecostomi (Holostei + Teleosteomorpha), which would make pycnodonts the most basal group among neopterygian fishes. Pycnodontomorpha comprises the orders Gyrodontiformes containing the families Gyrodontidae and Mesturidae, and Pycnodontiformes, including all remaining taxa (Nursall 2010). In this application whenever the term pycnodont is used, it refers to the total group Pycnodontomorpha.
The fact that pycnodonts weathered both the Late Triassic/Early Jurassic and the K/Pg extinction events indicates that these fishes had a particularly successful evolutionary strategy. Indeed, their increasing raw species diversity through the Mesozoic is quite plainly seen in the fossil record (Late Triassic: 4; Early Jurassic: 2; Middle Jurassic: 16; Late Jurassic: 77; Early Cretaceous: 73; Late Cretaceous: 101 [only named and currently as valid considered species listed]). The increase in raw species numbers in the Late Cretaceous is mirrored in the great increase in morphological disparity (Marramà et al. 2016a). The increase in species diversity from the Middle Jurassic onwards indicates the first diversification event in the history of pycnodonts.
A steep drop in taxon number occurred from the Late Cretaceous to Palaeocene, which might indicate that the K/P boundary event also affected pycnodont fishes. The disappearance of most major lineages well before the K/P boundary, which was used by Kriwet (2001a) to reject an extinction event at this boundary might be related to the so-called Signor-Lipps effect. Most pycnodonts known from the Palaeocene also occur in the Late Cretaceous with the exception of members of Pycnodus, which seemingly originated in the Palaeogene. This pycnodont is the most derived member of Pycnodontomorpha and the last representative of this formerly diverse group in the Eocene before it vanished, too.
A popular hypothesis regarding the extinction of pycnodonts is the observation that many modern teleost groups common in coral reefs today arose at the same time that pycnodonts were beginning to decline (Bellwood 1996; 2003). Were the pycnodonts simply outcompeted by better-adapted teleosts or could there have been other factors in their extinction?
During the Mesozoic, pycnodonts also faced competition from shallow water adapted, shell crushing ginglymodian fishes. In this case, however, the ginglymodian fishes (with the exception of Lepisosteidae) perished at the K/Pg boundary. Are there correlated evolutionary trajectories in both groups that enabled them to survive?
The project applied for here tends to answer two major questions: 1) Are competition patterns within pycnodonts and between pycnodonts, ginglymodians and ecologically similar fishes detectable, and could it explain diversity and diversification patterns within pycnodonts and 2) did the rise of teleosts, particularly Acanthomorpha, lead to the extinction of the pycnodonts in the Eocene? Thus, this project focuses on biotic rather than abiotic effects influencing diversity patterns.


Goals:

The major goals of this project are to gain deeper insights and a better understanding of the mechanisms that determine the evolutionary history, success, and final extinction of a highly diverse clade of fishes (Pycnodontomorpha). It was demonstrated that pycnodont fishes were very successful, highly diversified and evidently well adapted to the habitats they occupied. It is hypothesized that they were an important and major element of marine as well as continental influenced fish faunas (e.g., Kriwet 2001a). Nevertheless, the reasons for (1) their seemingly rapid diversification in the Early Mesozoic, (2) their subsequent success and thus their possible superiority over other fish groups inhabiting same environments (e.g., Ginglymodi), (3) their habitat use (= facies depending distribution) and possible size aggregations due to ontogenetic shifts, (4) diversity fluctuations in, i.e., relation to abiotic crises (e.g., Cenomanian/Turonian and K/P boundary events, environmental changes) or biotic factors (e.g., competition), and (5) the events triggering their final disappearance more or less simultaneously with the appearance and evolution of teleostean groups, which are considered to be important elements of modern coral-fish assemblages are ambiguous or have not been addressed with rigorous analytical methods up to now. The proposed project intends to find answers to these still not fully understood and varied aspects, which (in addition with already known traits such as feeding kinematics) will help understanding the evolutionary history of this important group and thus has the potential to identify universal evolutionary processes.

Team

  • Univ.-Prof. Dr. Jürgen Kriwet (PI) Read more
  • John J. Cawles, MSc (Predoctoral Researcher)
  • Iris Fuchs, BSc (Student Assistent)



Research Projects:

Batchelor and master students (Palaeobiology, Zoology, Ecology) are welcome to conduct projects for their thesis within this project. Projects range from analytical studies employing rigorous mathematical approaches to analysing calcification patterns in skeletal elements of Antarctic fishes and taxonomic evaluations. As a Batcherlor or Masterstudent in the Vertebrate Palaeobiology Group, you will work in a very active and dynamic group on applied research projects.

For more information please contact:

Univ.-Prof. Dr. Jürgen Kriwet
Department of Palaeontology
University of Vienna
Geozentrum
UZA 2
Althanstrasse 14
1090 Vienna, Austria
Tel: ++43-1-4277 / 535 20
e-mail: juergen.kriwet@univie.ac.at


Publications

For PDFs visit https://www.researchgate.net/profile/Juergen_Kriwet

Technical Papers
  • Stumpf, S., Ansorge, J., Pfaff, C. & Kriwet, J. in press. Early Jurassic diversification of pycnodontiform fishes (Actinopterygii, Neopterygii) after the end-Triassic extinction event: Evidence from a new genus and species, Grimmenodon aureum. Journal of Vertebrate Paleontology.
  • Cawley, J.J. & Kriwet, J. in press. Late Cretaceous pycnodontiform fishes from the Near East. Research & Knowledge.
  • Cawley, J.J. & Kriwet, J. in press. Possible sexual dimorphism in Pankowskichthys (Neopterygii, Pycnodontiformes) from the Cenomanian, Haqel, Lebanon. Research & Knowledge.
  • Cawley, J.J. & Kriwet, J. in press. A new pycnodont fish, Scalacurvichthys naishii, gen. et sp. nov., from the Late Cretaceous of the Middle East. Journal of Systematic Palaeontology.
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Elasmobranch fishes (sharks, skates, and rays) of the Adriatic Sea



Background & Goals:

Elasmobranch (sharks, rays, and skates) populations are seriously endangered because of direct and indirect human impacts. As a consequence of intense exploitation, many species are listed in the Red List by the International Union for Conservation of Nature (IUCN) either as vulnerable or endangered. They are exceedingly vulnerable due to their low growth rates, late sexual maturi-ty and low fecundity. Nevertheless, no reliable studies are available for several parts of the Medi-terranean Sea and it currently is difficult to predict how reduction and/or loss of the top predators will modify marine ecosystems.The Adriatic Sea as part of the Mediterranean Sea is a semi-closed basin occupying the northernmost Mediterranean section. It extends from northwest to southeast for almost 800 km and has an averaged width of 200 km. The Strait of Otranto connects the sub-basin to the Ionian Sea and enables water exchange with the Mediterranean Sea. The northern Adriatic show a 35 m mean depth with a slight slope to the middle part which has an average depth of 140 m. The middle Adriatic is characterized by two depressions reaching 273 m maximum depth. The south-ern sub-basin has a steep continental slope and an abyssal plain. The south Adriatic Pit reaches 1330 m maximum depth. The Adriatic is a shallow sea and most area (around 73 %) is less than 200 m deep. It is a temperate warm sea and extremes of surface temperature range from 6 ºC to 29 ºC. Even the deepest layers are generally above 10 ºC. In winter central and northern parts are 8 to 10 ºC colder than the south Adriatic. The Adriatic basin has generally a cyclonic circulation with seasonal determining sub-basin gyres (AdriaMed, 2005). In the Adriatic Sea 28 sharks, 24 batoids and one chimaera are known as permanent resident or occasionally visiting.The Kvarner area is a part of the northern Adriatic Sea and divided into Rijeka Bay, the Kvarner Bay, Kvarnerić and the Velebit and Vinodol channels. The flat Rijeka Bay is about 60 m deep as well as the Vinodol Channel that decreases further north to a depth of under 40 m. There are narrow and elongated parts between the islands Krk to Rab and Rab to Pag which ex-ceed 100 m depth. The Krusija Channel is located between the islands Cres and Plavnik and shows the Northern Adriatic deepest point of 125 m. Most of the Kvarner area seafloor is covred by muddy and sandy sediments.The goals of this project are to (1) establish the taxonomic diversity of sharks, rays, and skates in the Kvarner bay, (2) construe the state of populations, (3) describe new discoveries, and (4) ascertain the implementation of possible conservation measurements.

Team

  • Univ.-Prof. Dr. Jürgen Kriwet (PI) Read more
  • Anna Schipany (MSc student)



For more information please contact:

Univ.-Prof. Dr. Jürgen Kriwet
Department of Palaeontology
University of Vienna
Geozentrum
UZA 2
Althanstrasse 14
1090 Vienna, Austria
Tel: ++43-1-4277 / 535 20
e-mail: juergen.kriwet@univie.ac.at


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Systematic revision of the Eocene sharks (Chondrichthyes) from Bolca Lagerstätte, Italy

(Ernst Mach Grant, Ernst Mach - worldwide)



Primary Investigator: Dr. Marramà, G.


Goals

The goal of the project is to review the systematics of the Eocene sharks from the Italian Bolca Lagerstätte, in order to interpret their palaeobiological, palaeoecological and biogeographic significance. Special attention will be paid to the detailed anatomical comparison with their living and extinct relatives. The Eocene (50 million years) Konservat-Lagerstätte of Bolca, in Italy, is one of the most famous palaeontological sites in the world. Although more than 100,000 fish specimens were collected from this deposit during the last four century and more than 230 taxa were erected, several aspects regarding the palaeobiodiversity and the evolutionary significance of several fish groups have been neglected or underestimated. In particular, Eocene sharks of Bolca lack of a modern perspective from a systematic and taxonomic point of view. This project will be therefore a contribution to the knowledge of one of the most famous and well-studied palaeontological sites of the world, in order to improve our understanding about the palaeoecology and palaeoenvironment of Bolca, also providing an evolutionary significance for their cartilaginous fishes, after the end-Cretaceous extinction.

Team

  • Dr. Marramà, G. (PI)
  • Univ.-Prof. Dr. Jürgen Kriwet

b>Publications

For PDFs visit https://www.researchgate.net/profile/Juergen_Kriwet

Technical Papers
  • Marramà, G., Carnevale, G., Engelbrecht, A., Claeson, K.M., Zorzin, R., Fornasiero, M. & Kriwet, J. in review. A synoptic review of the Eocene (Ypresian) cartilaginous fishes (Chondrichthyes: Holocephali, Elasmobranchii) of the Bolca Konservat-Lagertätte, Italy. Paläontologische Zeitschrift.
  • Marramà, G., Claeson, K.M., Carnevale, C., Kriwet, J. submitted. Revision of Eocene electric rays (Torpediniformes, Batomorphii) from the Bolca Konservat-Lagerstätte, Italy, reveals the first fossil embryo in situ in batoids and provides new insights into the origin of trophic novelties in coral reef fishes. Journal of Systematic Palaeontology.
  • Marramà, G., Engelbrecht, A., Carnevale, G. & Kriwet, J. submitted. Eocene sand tiger sharks (Lamniformes, Odontaspididae) from the Bolca Konservat-Lagerstätte, Italy: Palaeobiology, palaeobiogeography and evolutionary significance. Historical Biology.

See here for more information Link

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