Paleobiology
Research topics
Evolution and functional biology of reptiles, evolution and functional morphology of mammals, evolution and development of conodonts, Triassic ecosystems, origins of animals in the fossil record, origin of molluscs, biogeography, evolution and embryogenesis of water fleas
Specialised equipment
- Critical Point Dryer
- Electromagnetic separator
- Pneumatic needle
- Vacuum evaporator
Methods
Chemical techniques of extracting fossils from various types of sedimentary rocks, electron microscopy, electromagnetic or heavy liquid separation, computed tomography, phylogenetic analyses, dietary reconstructions.
Publications review
Žliobaitė, Indrė; Fortelius, Mikael; Bernor, Raymond L.; Ostende, Lars W. Hoek; Janis, Christine M.; Lintulaakso, Kari; Säilä, Laura K.; Werdelin, Lars; Casanovas-Vilar, Isaac; Croft, Darin A.; Flynn, Lawrence J.; Hopkins, Samantha S. B.; Kaakinen, Anu; Kordos, László; Kostopoulos, Dimitris S.; Pandolfi, Luca; Rowan, John; Tesakov, Alexey; Vislobokova, Innessa; Zhang, Zhaoqun; Aiglstorfer, Manuela; Alba, David M.; Arnal, Michelle; Antoine, Pierre-Olivier; Belmaker, Miriam; Bilgin, Melike; Boisserie, Jean-Renaud; Borths, Matthew R.; Cooke, Siobhán B.; Dam, Jan A.; Delson, Eric; Eronen, Jussi T.; Fox, David; Friscia, Anthony R.; Furió, Marc; Giaourtsakis, Ioannis X.; Holbrook, Luke; Hunter, John; López-Torres, Sergi; Ludtke, Joshua; Minwer-Barakat, Raef; Made, Jan; Mennecart, Bastien; Pushkina, Diana; Rook, Lorenzo; Saarinen, Juha; Samuels, Joshua X.; Sanders, William; Silcox, Mary T.; Vepsäläinen, Jouni
The NOW Database of Fossil Mammals Book Chapter
In: Casanovas-Vilar, Isaac; Ostende, Lars W. Hoek; Janis, Christine M.; Saarinen, Juha (Ed.): Evolution of Cenozoic Land Mammal Faunas and Ecosystems: 25 Years of the NOW Database of Fossil Mammals, pp. 33–42, Springer International Publishing, Cham, 2023, ISBN: 978-3-031-17491-9.
@inbook{Žliobaitė2023,
title = {The NOW Database of Fossil Mammals},
author = {Indrė Žliobaitė and Mikael Fortelius and Raymond L. Bernor and Lars W. Hoek Ostende and Christine M. Janis and Kari Lintulaakso and Laura K. Säilä and Lars Werdelin and Isaac Casanovas-Vilar and Darin A. Croft and Lawrence J. Flynn and Samantha S. B. Hopkins and Anu Kaakinen and László Kordos and Dimitris S. Kostopoulos and Luca Pandolfi and John Rowan and Alexey Tesakov and Innessa Vislobokova and Zhaoqun Zhang and Manuela Aiglstorfer and David M. Alba and Michelle Arnal and Pierre-Olivier Antoine and Miriam Belmaker and Melike Bilgin and Jean-Renaud Boisserie and Matthew R. Borths and Siobhán B. Cooke and Jan A. Dam and Eric Delson and Jussi T. Eronen and David Fox and Anthony R. Friscia and Marc Furió and Ioannis X. Giaourtsakis and Luke Holbrook and John Hunter and Sergi López-Torres and Joshua Ludtke and Raef Minwer-Barakat and Jan Made and Bastien Mennecart and Diana Pushkina and Lorenzo Rook and Juha Saarinen and Joshua X. Samuels and William Sanders and Mary T. Silcox and Jouni Vepsäläinen},
editor = {Isaac Casanovas-Vilar and Lars W. Hoek Ostende and Christine M. Janis and Juha Saarinen},
url = {https://doi.org/10.1007/978-3-031-17491-9_3},
doi = {10.1007/978-3-031-17491-9_3},
isbn = {978-3-031-17491-9},
year = {2023},
date = {2023-08-09},
urldate = {2023-01-01},
booktitle = {Evolution of Cenozoic Land Mammal Faunas and Ecosystems: 25 Years of the NOW Database of Fossil Mammals},
pages = {33–42},
publisher = {Springer International Publishing},
address = {Cham},
abstract = {NOW (New and Old Worlds) is a global database of fossil mammal occurrences, currently containing around 68,000 locality-species entries. The database spans the last 66 million years, with its primary focus on the last 23 million years. Whereas the database contains recordsNOW Databaserecords from all continents, the main focus and coverage of the database historically has been on Eurasia. The database includes primarily, but not exclusively, terrestrial mammals. It covers a large part of the currently known mammalian fossil record, focusing on classical and actively researched fossil localities. The database is managed in collaboration with an international advisory board of experts. Rather than a static archive, it emphasizes the continuous integration of new knowledge of the communityNOW Databasedatacuration in, data curationDatacuration, and consistencyNOW Databaseconsistency of scientific interpretations. The database records species occurrences at localities worldwide, as well as ecologicalEcological characteristics of fossil species, geological contextsGeologic/geologicalcontext of localities and more. The NOW database is primarily used for two purposes: (1) queries about occurrences of particular taxa, their characteristics and properties of localities in the spirit of an encyclopedia; and (2) large scale research and quantitative analyses of evolutionary processes, patterns, reconstructing past environments, as well as interpreting evolutionary contexts. The data are fully open, no logging in or community membership is necessary for using the data for any purpose.},
keywords = {},
pubstate = {published},
tppubtype = {inbook}
}
NOW (New and Old Worlds) is a global database of fossil mammal occurrences, currently containing around 68,000 locality-species entries. The database spans the last 66 million years, with its primary focus on the last 23 million years. Whereas the database contains recordsNOW Databaserecords from all continents, the main focus and coverage of the database historically has been on Eurasia. The database includes primarily, but not exclusively, terrestrial mammals. It covers a large part of the currently known mammalian fossil record, focusing on classical and actively researched fossil localities. The database is managed in collaboration with an international advisory board of experts. Rather than a static archive, it emphasizes the continuous integration of new knowledge of the communityNOW Databasedatacuration in, data curationDatacuration, and consistencyNOW Databaseconsistency of scientific interpretations. The database records species occurrences at localities worldwide, as well as ecologicalEcological characteristics of fossil species, geological contextsGeologic/geologicalcontext of localities and more. The NOW database is primarily used for two purposes: (1) queries about occurrences of particular taxa, their characteristics and properties of localities in the spirit of an encyclopedia; and (2) large scale research and quantitative analyses of evolutionary processes, patterns, reconstructing past environments, as well as interpreting evolutionary contexts. The data are fully open, no logging in or community membership is necessary for using the data for any purpose.
Szczygielski, Tomasz; Piechowski, Rafał
Limb anatomy of the Triassic turtles: appendicular osteology of Proterochersis (Testudinata, Proterochersidae) Journal Article
In: Zoological Journal of the Linnean Society, pp. zlad057, 2023, ISSN: 0024-4082.
@article{10.1093/zoolinnean/zlad057,
title = {Limb anatomy of the Triassic turtles: appendicular osteology of Proterochersis (Testudinata, Proterochersidae)},
author = {Tomasz Szczygielski and Rafał Piechowski},
url = {https://doi.org/10.1093/zoolinnean/zlad057},
doi = {10.1093/zoolinnean/zlad057},
issn = {0024-4082},
year = {2023},
date = {2023-07-25},
urldate = {2023-01-01},
journal = {Zoological Journal of the Linnean Society},
pages = {zlad057},
abstract = {The turtle locomotor system is heavily modified owing to the severe impact of development of the shell on the body plan of these reptiles. Although limb and girdle osteology of the earliest, Triassic turtles is relatively well understood in general, the exact impacts of variability, ontogeny and preservation (e.g. deformation) on the observed morphologies have rarely been considered in detail. Here, we describe in detail and document the osteology and intraspecific variability of the limbs and girdles of Proterochersis spp., the basalmost true turtles (Testudinata). We also provide a synthesis of currently available data and detailed comparisons with other Triassic stem turtles to gain a better understanding of the diagnostic value of the early turtle appendicular skeleton and to pave the way for future biomechanical and functional studies. Our data suggest that Proterochersis spp. could be at least partly aquatic and could change their preferred habitat during ontogeny, with larger (and, presumably, older) specimens presenting more characters suggestive of a more terrestrial environment.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The turtle locomotor system is heavily modified owing to the severe impact of development of the shell on the body plan of these reptiles. Although limb and girdle osteology of the earliest, Triassic turtles is relatively well understood in general, the exact impacts of variability, ontogeny and preservation (e.g. deformation) on the observed morphologies have rarely been considered in detail. Here, we describe in detail and document the osteology and intraspecific variability of the limbs and girdles of Proterochersis spp., the basalmost true turtles (Testudinata). We also provide a synthesis of currently available data and detailed comparisons with other Triassic stem turtles to gain a better understanding of the diagnostic value of the early turtle appendicular skeleton and to pave the way for future biomechanical and functional studies. Our data suggest that Proterochersis spp. could be at least partly aquatic and could change their preferred habitat during ontogeny, with larger (and, presumably, older) specimens presenting more characters suggestive of a more terrestrial environment.
Czepiński, Łukasz
Skull of a dromaeosaurid Shri devi from the Upper Cretaceous of the Gobi Desert suggests convergence to the North American forms Journal Article
In: Acta Palaeontologica Polonica, vol. 68, 2023.
@article{Czepiński_2023,
title = {Skull of a dromaeosaurid Shri devi from the Upper Cretaceous of the Gobi Desert suggests convergence to the North American forms},
author = {Łukasz Czepiński},
doi = {10.4202/app.01065.2023},
year = {2023},
date = {2023-06-21},
urldate = {2023-06-21},
journal = {Acta Palaeontologica Polonica},
volume = {68},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
López-Torres, Sergi; Bertrand, Ornella C.; Lang, Madlen M.; Fostowicz-Frelik, Łucja; Silcox, Mary T.; Meng, Jin
Cranial endocast of Anagale gobiensis (Anagalidae) and its implications for early brain evolution in Euarchontoglires Journal Article
In: Palaeontology, vol. 66, no. 3, pp. e12650, 2023.
@article{https://doi.org/10.1111/pala.12650,
title = {Cranial endocast of Anagale gobiensis (Anagalidae) and its implications for early brain evolution in Euarchontoglires},
author = {Sergi López-Torres and Ornella C. Bertrand and Madlen M. Lang and Łucja Fostowicz-Frelik and Mary T. Silcox and Jin Meng},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/pala.12650},
doi = {https://doi.org/10.1111/pala.12650},
year = {2023},
date = {2023-06-01},
urldate = {2023-06-01},
journal = {Palaeontology},
volume = {66},
number = {3},
pages = {e12650},
abstract = {Abstract Anagalids are an extinct group of primitive mammals from the Asian Palaeogene thought to be possible basal members of Glires. Anagalid material is rare, with only a handful of crania known. Here we describe the first virtual endocast of an anagalid, based on the holotype of Anagale gobiensis (AMNH 26079; late Eocene, China), which allows for comparison with published endocasts from fossil members of modern euarchontogliran lineages (i.e. primates, rodents, lagomorphs). The endocast displays traits often observed in fossorial mammals, such as relatively small petrosal lobules and a low neocortical ratio, which would be consistent with previous inferences about use of subterranean food sources based on heavy dental wear. In fact, Anagale gobiensis has the lowest neocortical ratio yet recorded for a euarchontogliran. This species was olfaction-driven, based on the relatively large olfactory bulbs and laterally expansive palaeocortex. The endocast supports previous inferences that relatively large olfactory bulbs, partial midbrain exposure and low encephalization quotient are ancestral for Euarchontoglires, although the likely fossorial adaptations of Anagale gobiensis may also partly explain these traits. While Anagale gobiensis is a primitive mammal in many aspects, some of its derived endocranial traits point towards a new, different trajectory of brain evolution within Euarchontoglires.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Abstract Anagalids are an extinct group of primitive mammals from the Asian Palaeogene thought to be possible basal members of Glires. Anagalid material is rare, with only a handful of crania known. Here we describe the first virtual endocast of an anagalid, based on the holotype of Anagale gobiensis (AMNH 26079; late Eocene, China), which allows for comparison with published endocasts from fossil members of modern euarchontogliran lineages (i.e. primates, rodents, lagomorphs). The endocast displays traits often observed in fossorial mammals, such as relatively small petrosal lobules and a low neocortical ratio, which would be consistent with previous inferences about use of subterranean food sources based on heavy dental wear. In fact, Anagale gobiensis has the lowest neocortical ratio yet recorded for a euarchontogliran. This species was olfaction-driven, based on the relatively large olfactory bulbs and laterally expansive palaeocortex. The endocast supports previous inferences that relatively large olfactory bulbs, partial midbrain exposure and low encephalization quotient are ancestral for Euarchontoglires, although the likely fossorial adaptations of Anagale gobiensis may also partly explain these traits. While Anagale gobiensis is a primitive mammal in many aspects, some of its derived endocranial traits point towards a new, different trajectory of brain evolution within Euarchontoglires.
López-Torres, Sergi; Bhagat, Raj; Bertrand, Ornella C.; Silcox, Mary T.; Fostowicz-Frelik, Łucja
Locomotor behavior and hearing sensitivity in an early lagomorph reconstructed from the bony labyrinth Journal Article
In: Ecology and Evolution, vol. 13, no. 3, pp. e9890, 2023.
@article{LopezE&E2023,
title = {Locomotor behavior and hearing sensitivity in an early lagomorph reconstructed from the bony labyrinth},
author = {Sergi López-Torres and Raj Bhagat and Ornella C. Bertrand and Mary T. Silcox and Łucja Fostowicz-Frelik},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/ece3.9890},
doi = {https://doi.org/10.1002/ece3.9890},
year = {2023},
date = {2023-03-18},
urldate = {2023-03-18},
journal = {Ecology and Evolution},
volume = {13},
number = {3},
pages = {e9890},
abstract = {Abstract The structure of the bony labyrinth is highly informative with respect to locomotor agility (semicircular canals [SCC]) and hearing sensitivity (cochlear and oval windows). Here, we reconstructed the agility and hearing sensitivity of the stem lagomorph Megalagus turgidus from the early Oligocene of the Brule Formation of Nebraska (USA). Megalagus has proportionally smaller SCCs with respect to its body mass compared with most extant leporids but within the modern range of variability, suggesting that it was less agile than most of its modern relatives. A level of agility for Megalagus within the range of modern rabbits is consistent with the evidence from postcranial elements. The hearing sensitivity for Megalagus is in the range of extant lagomorphs for both low- and high-frequency sounds. Our data show that by the early Oligocene stem lagomorphs had already attained fundamentally rabbit-like hearing sensitivity and locomotor behavior, even though Megalagus was not a particularly agile lagomorph. This is likely because Megalagus was more of a woodland dweller than an open-habitat runner. The study of sensory evolution in Lagomorpha is practically unknown, and these results provide first advances in understanding the primitive stages for the order and how the earliest members of this clade perceived their environment.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Abstract The structure of the bony labyrinth is highly informative with respect to locomotor agility (semicircular canals [SCC]) and hearing sensitivity (cochlear and oval windows). Here, we reconstructed the agility and hearing sensitivity of the stem lagomorph Megalagus turgidus from the early Oligocene of the Brule Formation of Nebraska (USA). Megalagus has proportionally smaller SCCs with respect to its body mass compared with most extant leporids but within the modern range of variability, suggesting that it was less agile than most of its modern relatives. A level of agility for Megalagus within the range of modern rabbits is consistent with the evidence from postcranial elements. The hearing sensitivity for Megalagus is in the range of extant lagomorphs for both low- and high-frequency sounds. Our data show that by the early Oligocene stem lagomorphs had already attained fundamentally rabbit-like hearing sensitivity and locomotor behavior, even though Megalagus was not a particularly agile lagomorph. This is likely because Megalagus was more of a woodland dweller than an open-habitat runner. The study of sensory evolution in Lagomorpha is practically unknown, and these results provide first advances in understanding the primitive stages for the order and how the earliest members of this clade perceived their environment.
Silcox, Mary T.; López-Torres, Sergi
Primate Origins: The Earliest Primates and Euprimates and Their Role in the Evolution of the Order Book Chapter
In: Chapter 22, pp. 365-380, John Wiley & Sons, Ltd, 2023, ISBN: 9781119828075.
@inbook{Sergi2023,
title = {Primate Origins: The Earliest Primates and Euprimates and Their Role in the Evolution of the Order},
author = {Mary T. Silcox and Sergi López-Torres},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/9781119828075.ch22},
doi = {https://doi.org/10.1002/9781119828075.ch22},
isbn = {9781119828075},
year = {2023},
date = {2023-03-15},
urldate = {2023-03-15},
pages = {365-380},
publisher = {John Wiley & Sons, Ltd},
chapter = {22},
abstract = {This chapter provides an overview of the fossil record for the key early euprimate groups, and for the plesiadapiforms, and discusses how this record relates to Primate Origins and to the origins of Strepsirrhini and Anthropoidea. Adapis was the first fossil primate to be named, although the reference in its name to Apis, the sacred Egyptian bull, implies some initial confusion about its identity. Primitive adapoids and omomyoids are very similar dentally, although adapoids do possess two apparently derived features of the dentition that allows them to be distinguished. Traditionally, omomyoids have been viewed as tarsier-like, in contrast to the lemur-like adapoids. The endocasts of plesiadapiforms indicate that the brain had not yet evolved a euprimate-like expansion of the neocortex, with notably larger olfactory bulbs relative to the overall size of the brain compared to even the most primitive euprimates.},
keywords = {},
pubstate = {published},
tppubtype = {inbook}
}
This chapter provides an overview of the fossil record for the key early euprimate groups, and for the plesiadapiforms, and discusses how this record relates to Primate Origins and to the origins of Strepsirrhini and Anthropoidea. Adapis was the first fossil primate to be named, although the reference in its name to Apis, the sacred Egyptian bull, implies some initial confusion about its identity. Primitive adapoids and omomyoids are very similar dentally, although adapoids do possess two apparently derived features of the dentition that allows them to be distinguished. Traditionally, omomyoids have been viewed as tarsier-like, in contrast to the lemur-like adapoids. The endocasts of plesiadapiforms indicate that the brain had not yet evolved a euprimate-like expansion of the neocortex, with notably larger olfactory bulbs relative to the overall size of the brain compared to even the most primitive euprimates.
Silcox, Mary T; Bertrand, Ornella C; Harrington, Arianna R; Lang, Madlen M; Martin-Flores, Gabriela A San; López-Torres, Sergi
Early Evolution of the Brain in Primates and Their Close Kin Book Chapter
In: Dozo, María Teresa; Paulina-Carabajal, Ariana; Macrini, Thomas E; Walsh, Stig (Ed.): Chapter 12, pp. 457–506, Springer Cham, Switzerland, 2023, ISBN: 978-3-031-13983-3.
@inbook{Silcox_Bertrand_Harrington_Lang_SanMartin-Flores_Lopez-Torres_2023,
title = {Early Evolution of the Brain in Primates and Their Close Kin},
author = {Mary T Silcox and Ornella C Bertrand and Arianna R Harrington and Madlen M Lang and Gabriela A San Martin-Flores and Sergi López-Torres},
editor = {María Teresa Dozo and Ariana Paulina-Carabajal and Thomas E Macrini and Stig Walsh},
url = {https://link.springer.com/chapter/10.1007/978-3-031-13983-3_12},
isbn = {978-3-031-13983-3},
year = {2023},
date = {2023-01-01},
urldate = {2023-01-01},
pages = {457–506},
publisher = {Springer Cham},
address = {Switzerland},
chapter = {12},
abstract = {The interpretation of early primate endocasts can be framed around four critical questions: (1) What are accurate estimates of endocranial capacity for known euprimate specimens? (2) What does the available data for stem primates tell us with respect to the earliest phases of primate brain evolution? (3) How should relative brain size be assessed? and (4) What is the appropriate comparative context for interpreting fossil primate endocasts? The widespread availability of CT data has allowed for better estimates of endocranial volume (#1), and for more data from stem primates (#2). From these data it is clear that the earliest primates had brains that were little differentiated in terms of form or size from their ancestors, although there might have been some modest increase in the relative size of the neocortex. Major changes in shape occurred at the euprimate node, with expansions in the temporal and occipital lobes (reflected in an expanded neocortex), and a lack of expansion in the olfactory bulbs. The brain of early fossil euprimates nonetheless still displayed primitive features such as narrow frontal lobes. Questions #3 and #4 remain contentious, although a much-expanded comparative sample of fossil endocasts allows for new perspectives on these issues.},
keywords = {},
pubstate = {published},
tppubtype = {inbook}
}
The interpretation of early primate endocasts can be framed around four critical questions: (1) What are accurate estimates of endocranial capacity for known euprimate specimens? (2) What does the available data for stem primates tell us with respect to the earliest phases of primate brain evolution? (3) How should relative brain size be assessed? and (4) What is the appropriate comparative context for interpreting fossil primate endocasts? The widespread availability of CT data has allowed for better estimates of endocranial volume (#1), and for more data from stem primates (#2). From these data it is clear that the earliest primates had brains that were little differentiated in terms of form or size from their ancestors, although there might have been some modest increase in the relative size of the neocortex. Major changes in shape occurred at the euprimate node, with expansions in the temporal and occipital lobes (reflected in an expanded neocortex), and a lack of expansion in the olfactory bulbs. The brain of early fossil euprimates nonetheless still displayed primitive features such as narrow frontal lobes. Questions #3 and #4 remain contentious, although a much-expanded comparative sample of fossil endocasts allows for new perspectives on these issues.
Scott, Craig S; López-Torres, Sergi; Silcox, Mary T; Fox, Richard C
New paromomyids (Mammalia, Primates) from the Paleocene of southwestern Alberta, Canada, and an analysis of paromomyid interrelationships Journal Article
In: Journal of Paleontology, pp. 1–22, 2023.
@article{scott2023new,
title = {New paromomyids (Mammalia, Primates) from the Paleocene of southwestern Alberta, Canada, and an analysis of paromomyid interrelationships},
author = {Craig S Scott and Sergi López-Torres and Mary T Silcox and Richard C Fox},
url = {https://www.cambridge.org/core/journals/journal-of-paleontology/article/new-paromomyids-mammalia-primates-from-the-paleocene-of-southwestern-alberta-canada-and-an-analysis-of-paromomyid-interrelationships/85328AE223A9AE66A2948F6FB06712CD},
year = {2023},
date = {2023-01-01},
urldate = {2023-01-01},
journal = {Journal of Paleontology},
pages = {1--22},
publisher = {Cambridge University Press},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Uhlik, Marcin; Brzeziński, Tomasz
In: Crustaceana, vol. 95, iss. 8-9, pp. 907-923, 2022.
@article{Uhlik_2022,
title = {Embryogeny of Bosmina longirostris (O. F. Müller, 1785) (Bosminidae) confirms a close relationship to the superfamily Eurycercoidea (Branchiopoda, Cladocera, Anomopoda)},
author = {Marcin Uhlik and Tomasz Brzeziński},
doi = {10.1163/15685403-bja10236},
year = {2022},
date = {2022-11-18},
urldate = {2022-11-18},
journal = {Crustaceana},
volume = {95},
issue = {8-9},
pages = {907-923},
abstract = {The embryonic stages of the anomopod Bosmina longirostris of the family Bosminidae were elucidated by scanning electron microscopy. Along with the corresponding stages of Bosmina coregoni described by Kotov (2001), these findings have enabled a comparison to Dunhevedia crassa, as a representative species of the family Chydoridae, and to Eurycercus lamellatus of the family Eurycercidae. In general, the developmental patterns are similar in these four species, particularly from blastulation to the first instar. The principal difference during embryogenesis is that in D. crassa and B. longirostris five thoracopods (six in E. lamellatus) are differentiated already with endo- and exopodites.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The embryonic stages of the anomopod Bosmina longirostris of the family Bosminidae were elucidated by scanning electron microscopy. Along with the corresponding stages of Bosmina coregoni described by Kotov (2001), these findings have enabled a comparison to Dunhevedia crassa, as a representative species of the family Chydoridae, and to Eurycercus lamellatus of the family Eurycercidae. In general, the developmental patterns are similar in these four species, particularly from blastulation to the first instar. The principal difference during embryogenesis is that in D. crassa and B. longirostris five thoracopods (six in E. lamellatus) are differentiated already with endo- and exopodites.
Tałanda, Mateusz; Fernandez, Vincent; Panciroli, Elsa; Evans, Susan E; Benson, Roger J
Synchrotron tomography of a stem lizard elucidates early squamate anatomy Journal Article
In: Nature, vol. 611, no. 7934, pp. 99-104, 2022.
@article{talanda2022synchrotron,
title = {Synchrotron tomography of a stem lizard elucidates early squamate anatomy},
author = {Mateusz Tałanda and Vincent Fernandez and Elsa Panciroli and Susan E Evans and Roger J Benson},
doi = {10.1038/s41586-022-05332-6},
year = {2022},
date = {2022-10-26},
urldate = {2022-01-01},
journal = {Nature},
volume = {611},
number = {7934},
pages = {99-104},
publisher = {Nature Publishing Group},
abstract = {Squamates (lizards and snakes) include more than 10,000 living species, descended from an ancestor that diverged more than 240 million years ago from that of their closest living relative, Sphenodon. However, a deficiency of fossil evidence1,2,3,4,5,6,7, combined with serious conflicts between molecular and morphological accounts of squamate phylogeny8,9,10,11,12,13 (but see ref. 14), has caused uncertainty about the origins and evolutionary assembly of squamate anatomy. Here we report the near-complete skeleton of a stem squamate, Bellairsia gracilis, from the Middle Jurassic epoch of Scotland, documented using high-resolution synchrotron phase-contrast tomography. Bellairsia shares numerous features of the crown group, including traits related to cranial kinesis (an important functional feature of many extant squamates) and those of the braincase and shoulder girdle. Alongside these derived traits, Bellairsia also retains inferred ancestral features including a pterygoid–vomer contact and the presence of both cervical and dorsal intercentra. Phylogenetic analyses return strong support for Bellairsia as a stem squamate, suggesting that several features that it shares with extant gekkotans are plesiomorphies, consistent with the molecular phylogenetic hypothesis that gekkotans are early-diverging squamates. We also provide confident support of stem squamate affinities for the enigmatic Oculudentavis. Our findings indicate that squamate-like functional features of the suspensorium, braincase and shoulder girdle preceded the origin of their palatal and vertebral traits and indicate the presence of advanced stem squamates as persistent components of terrestrial assemblages up to at least the middle of the Cretaceous period.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Squamates (lizards and snakes) include more than 10,000 living species, descended from an ancestor that diverged more than 240 million years ago from that of their closest living relative, Sphenodon. However, a deficiency of fossil evidence1,2,3,4,5,6,7, combined with serious conflicts between molecular and morphological accounts of squamate phylogeny8,9,10,11,12,13 (but see ref. 14), has caused uncertainty about the origins and evolutionary assembly of squamate anatomy. Here we report the near-complete skeleton of a stem squamate, Bellairsia gracilis, from the Middle Jurassic epoch of Scotland, documented using high-resolution synchrotron phase-contrast tomography. Bellairsia shares numerous features of the crown group, including traits related to cranial kinesis (an important functional feature of many extant squamates) and those of the braincase and shoulder girdle. Alongside these derived traits, Bellairsia also retains inferred ancestral features including a pterygoid–vomer contact and the presence of both cervical and dorsal intercentra. Phylogenetic analyses return strong support for Bellairsia as a stem squamate, suggesting that several features that it shares with extant gekkotans are plesiomorphies, consistent with the molecular phylogenetic hypothesis that gekkotans are early-diverging squamates. We also provide confident support of stem squamate affinities for the enigmatic Oculudentavis. Our findings indicate that squamate-like functional features of the suspensorium, braincase and shoulder girdle preceded the origin of their palatal and vertebral traits and indicate the presence of advanced stem squamates as persistent components of terrestrial assemblages up to at least the middle of the Cretaceous period.
López-Torres, Sergi
Primate Evolution and the Emergence of Humans (Vertebrate Life 11th ed.) Book Chapter
In: Pough, Harvey; Bemis, William E.; McGuire, Betty Anne; Janis, Christine M. (Ed.): Chapter 24, pp. 557-585, Oxford University Press, New York, 11, 2022, ISBN: 978-0197564882.
@inbook{Lopez_primates_2022,
title = {Primate Evolution and the Emergence of Humans (Vertebrate Life 11th ed.)},
author = {Sergi López-Torres},
editor = { Harvey Pough and William E. Bemis and Betty Anne McGuire and Christine M. Janis },
url = {https://global.oup.com/academic/product/vertebrate-life-9780197564882?cc=us&lang=en#},
isbn = {978-0197564882},
year = {2022},
date = {2022-10-01},
urldate = {2022-10-01},
pages = {557-585},
publisher = {Oxford University Press},
address = {New York},
edition = {11},
chapter = {24},
abstract = {Primates have been a moderately successful group for most of the Cenozoic, although since the end of the Eocene they have been largely confined to tropical latitudes (with the exception of humans). Primates include not only the anthropoids—the group of apes and monkeys to which humans belong—but also the prosimians, animals such as bush babies and lemurs, and earlier less derived forms known only from the fossil record. Molecular techniques show that chimpanzees are the closest extant relatives of humans, and both molecular data and the fossil record indicate that the separation of humans from the African great apes occurred about 6.6 Ma. Fossils of Australopithecus—the sister taxon to our own genus, Homo—clearly show that bipedal walking arose before the appearance of a large brain. A diversity of new fossils has shown that early human evolution was much more complex and diverse than previously thought.},
keywords = {},
pubstate = {published},
tppubtype = {inbook}
}
Primates have been a moderately successful group for most of the Cenozoic, although since the end of the Eocene they have been largely confined to tropical latitudes (with the exception of humans). Primates include not only the anthropoids—the group of apes and monkeys to which humans belong—but also the prosimians, animals such as bush babies and lemurs, and earlier less derived forms known only from the fossil record. Molecular techniques show that chimpanzees are the closest extant relatives of humans, and both molecular data and the fossil record indicate that the separation of humans from the African great apes occurred about 6.6 Ma. Fossils of Australopithecus—the sister taxon to our own genus, Homo—clearly show that bipedal walking arose before the appearance of a large brain. A diversity of new fossils has shown that early human evolution was much more complex and diverse than previously thought.
Grau-Camats, Montserrat; Bertrand, Ornella C; Prieto, Jérome; López-Torres, Sergi; Silcox, Mary T; Casanovas-Vilar, Isaac
A Miopetaurista (Rodentia, Sciuridae) cranium from the Middle Miocene of Bavaria (Germany) and brain evolution in flying squirrels Journal Article
In: Papers in Palaeontology, vol. 8, no. 4, pp. e1454, 2022.
@article{grau2022miopetaurista,
title = {A Miopetaurista (Rodentia, Sciuridae) cranium from the Middle Miocene of Bavaria (Germany) and brain evolution in flying squirrels},
author = {Montserrat Grau-Camats and Ornella C Bertrand and Jérome Prieto and Sergi López-Torres and Mary T Silcox and Isaac Casanovas-Vilar},
doi = {10.1002/spp2.1454},
year = {2022},
date = {2022-07-25},
journal = {Papers in Palaeontology},
volume = {8},
number = {4},
pages = {e1454},
publisher = {Wiley Online Library},
abstract = {Flying squirrels (Sciurinae, Pteromyini) are the most successful group of gliding mammals. However, their fossil record mostly consists of isolated dental remains that provide very limited insights into their palaeobiology and evolution. The first skeleton of a fossil flying squirrel, belonging to the species Miopetaurista neogrivensis, has been described only recently. It presents all the diagnostic gliding-related postcranial features of its extant relatives and shows that this group has undergone very little morphological change for almost 12 myr. However, the associated cranium is badly crushed, and particular details of the cranial morphology cannot be described. Here, we describe a well-preserved cranium of the closely related Miopetaurista crusafonti from 12.5–12.0 Ma from Bavaria (Germany). Its cranial morphology is found to be almost identical to extant large flying squirrels, even in details such as the position of the foramina. The virtual endocast also shows close affinities to living large flying squirrels in morphology and in the relative volume of different brain regions, showing diagnostic features such as the size reduction of petrosal lobules and olfactory bulbs. However, the encephalization quotient (EQ) and neocortical ratio are lower than observed in extant flying squirrels. EQ is known to increase through time in squirrels, but might also be related to locomotion, given that arboreal and gliding squirrels display higher EQs than terrestrial ones. Because Miopetaurista was certainly a glider, its comparatively lower EQ and neocortical size support the existence of an independent trend of increasing EQ and neocortical complexity in this flying squirrel subclade.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Flying squirrels (Sciurinae, Pteromyini) are the most successful group of gliding mammals. However, their fossil record mostly consists of isolated dental remains that provide very limited insights into their palaeobiology and evolution. The first skeleton of a fossil flying squirrel, belonging to the species Miopetaurista neogrivensis, has been described only recently. It presents all the diagnostic gliding-related postcranial features of its extant relatives and shows that this group has undergone very little morphological change for almost 12 myr. However, the associated cranium is badly crushed, and particular details of the cranial morphology cannot be described. Here, we describe a well-preserved cranium of the closely related Miopetaurista crusafonti from 12.5–12.0 Ma from Bavaria (Germany). Its cranial morphology is found to be almost identical to extant large flying squirrels, even in details such as the position of the foramina. The virtual endocast also shows close affinities to living large flying squirrels in morphology and in the relative volume of different brain regions, showing diagnostic features such as the size reduction of petrosal lobules and olfactory bulbs. However, the encephalization quotient (EQ) and neocortical ratio are lower than observed in extant flying squirrels. EQ is known to increase through time in squirrels, but might also be related to locomotion, given that arboreal and gliding squirrels display higher EQs than terrestrial ones. Because Miopetaurista was certainly a glider, its comparatively lower EQ and neocortical size support the existence of an independent trend of increasing EQ and neocortical complexity in this flying squirrel subclade.
Dzik, Jerzy; Phong, Nguyen Duc; Thuy, Nguyen Thi; Swiś, Przemyslaw
Evolution and migration of conodonts and ammonoids near the end of Devonian recorded in distant localities Journal Article
In: Stratigraphy, vol. 19, no. 1, pp. 27-50, 2022.
@article{Dzik2022,
title = {Evolution and migration of conodonts and ammonoids near the end of Devonian recorded in distant localities},
author = {Jerzy Dzik and Nguyen Duc Phong and Nguyen Thi Thuy and Przemyslaw Swiś},
url = {https://www.micropress.org/microaccess/check/2272},
year = {2022},
date = {2022-03-15},
journal = {Stratigraphy},
volume = {19},
number = {1},
pages = {27-50},
abstract = {The Devonian-Carboniferous boundary is allegedly marked by one of the most catastrophic global extinctions associated with sedimentation of the Hangenberg black shale. A dense sampling of the Kowala section in the Holy Cross Mountains, Poland, challenges this view, showing that the faunal dynamics across the Hangenberg black shalewas not more dramatic than that across the preceding Kowala black shale. Quantitative analysis and biologically meaningful conodont apparatus study of the Kowala material offer probably the most complete record of faunal change in the latest Famennian and earliest Tournaisian among those sampled bed-by-bed for ammonoids and conodonts. It appears that the faunal dynamics of both cephalopods and conodonts was controlled by environmental changes that resulted in numerous immigrations and disappearances of particular lineages. Only a small fraction of lineages persisted long enough at the place, and transformed their morphology fast enough, to leave a record of their evolution. Most of the evolution apparently took place elsewhere. Locations of remote refugia where these lineages evolved in the time span bracketed by the Kowala and Hangenberg black shale events remain to be identified. Conodont apparatus study on geographically distant Vietnamese locality Cat Ba provides evidence that at least in the latest Famennian some conodont species unknown from Poland were present in Vietnam. Moreover, the contribution of species known from both localities to Polish and Vietnamese fossil assemblages was dramatically different.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The Devonian-Carboniferous boundary is allegedly marked by one of the most catastrophic global extinctions associated with sedimentation of the Hangenberg black shale. A dense sampling of the Kowala section in the Holy Cross Mountains, Poland, challenges this view, showing that the faunal dynamics across the Hangenberg black shalewas not more dramatic than that across the preceding Kowala black shale. Quantitative analysis and biologically meaningful conodont apparatus study of the Kowala material offer probably the most complete record of faunal change in the latest Famennian and earliest Tournaisian among those sampled bed-by-bed for ammonoids and conodonts. It appears that the faunal dynamics of both cephalopods and conodonts was controlled by environmental changes that resulted in numerous immigrations and disappearances of particular lineages. Only a small fraction of lineages persisted long enough at the place, and transformed their morphology fast enough, to leave a record of their evolution. Most of the evolution apparently took place elsewhere. Locations of remote refugia where these lineages evolved in the time span bracketed by the Kowala and Hangenberg black shale events remain to be identified. Conodont apparatus study on geographically distant Vietnamese locality Cat Ba provides evidence that at least in the latest Famennian some conodont species unknown from Poland were present in Vietnam. Moreover, the contribution of species known from both localities to Polish and Vietnamese fossil assemblages was dramatically different.
Pawlak, Wojciech; Rozwalak, Piotr; Sulej, Tomasz
Triassic fish faunas from Miedary (Upper Silesia, Poland) and their implications for understanding paleosalinity Journal Article
In: Palaeogeography, Palaeoclimatology, Palaeoecology, vol. 590, pp. 110860, 2022, ISSN: 0031-0182.
@article{Pawlak_2022,
title = {Triassic fish faunas from Miedary (Upper Silesia, Poland) and their implications for understanding paleosalinity},
author = {Wojciech Pawlak and Piotr Rozwalak and Tomasz Sulej},
url = {https://www.sciencedirect.com/science/article/abs/pii/S003101822200030X},
issn = {0031-0182},
year = {2022},
date = {2022-02-09},
urldate = {2022-01-01},
journal = {Palaeogeography, Palaeoclimatology, Palaeoecology},
volume = {590},
pages = {110860},
abstract = {We describe two new fish-dominated faunas from the Middle Triassic (Ladinian) Miedary site, Upper Silesia, Poland, and present a comparative analysis of Middle-to-Late Triassic vertebrate assemblages from the Germanic Basin, in order to explore the influence of salinity on faunal composition. The composition of the assemblage from dolomite beds at Miedary is similar to those from the Muschalkalk facies, whereas the assemblage from glauconite beds appears to be the first brackish vertebrate assemblage of the Serrolepis lake-type recognized from the eastern Germanic Basin. Comparative analysis of all sites, using hierarchical clustering, nonmetric multidimensional scaling, and principal component approaches, revealed the existence of vertebrate taxa associated withfreshwater, brackish and marine conditions, as well as euryhaline taxa with wide salinity preferences. Moreover, it confirms the brackish nature of Serrolepis-bearing assemblages, and suggests that Serrolepis suevicus is a brackish specialist, indicative of oligohaline to miohaline paleosalinities. The Middle-Late Triassic vertebrate faunas appear dominated by stenohaline taxa, with a conspicuous separation of species living in the freshwater and marine conditions. The euryhaline taxa are rare, and comprise Acrodus lateralis, Eusauropterygia, Lissodus nodosus, and Saurichthyiformes.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We describe two new fish-dominated faunas from the Middle Triassic (Ladinian) Miedary site, Upper Silesia, Poland, and present a comparative analysis of Middle-to-Late Triassic vertebrate assemblages from the Germanic Basin, in order to explore the influence of salinity on faunal composition. The composition of the assemblage from dolomite beds at Miedary is similar to those from the Muschalkalk facies, whereas the assemblage from glauconite beds appears to be the first brackish vertebrate assemblage of the Serrolepis lake-type recognized from the eastern Germanic Basin. Comparative analysis of all sites, using hierarchical clustering, nonmetric multidimensional scaling, and principal component approaches, revealed the existence of vertebrate taxa associated withfreshwater, brackish and marine conditions, as well as euryhaline taxa with wide salinity preferences. Moreover, it confirms the brackish nature of Serrolepis-bearing assemblages, and suggests that Serrolepis suevicus is a brackish specialist, indicative of oligohaline to miohaline paleosalinities. The Middle-Late Triassic vertebrate faunas appear dominated by stenohaline taxa, with a conspicuous separation of species living in the freshwater and marine conditions. The euryhaline taxa are rare, and comprise Acrodus lateralis, Eusauropterygia, Lissodus nodosus, and Saurichthyiformes.
Leonhard, Isabella; Shirley, Bryan; Murdock, Duncan J E; Repetski, John; Jarochowska, Emilia
Growth and feeding ecology of coniform conodonts Journal Article
In: PeerJ, vol. 9, pp. e12505, 2021, ISSN: 2167-8359.
@article{Leonhard2021,
title = {Growth and feeding ecology of coniform conodonts},
author = {Isabella Leonhard and Bryan Shirley and Duncan J E Murdock and John Repetski and Emilia Jarochowska},
doi = {10.7717/peerj.12505},
issn = {2167-8359},
year = {2021},
date = {2021-12-15},
journal = {PeerJ},
volume = {9},
pages = {e12505},
abstract = { Conodonts were the first vertebrates to develop mineralized dental tools, known as elements. Recent research suggests that conodonts were macrophagous predators and/or scavengers but we do not know how this feeding habit emerged in the earliest coniform conodonts, since most studies focus on the derived, ‘complex’ conodonts. Previous modelling of element position and mechanical properties indicate they were capable of food processing. A direct test would be provided through evidence of in vivo element crown tissue damage or through in vivo incorporated chemical proxies for a shift in their trophic position during ontogeny. Here we focus on coniform elements from two conodont taxa, the phylogenetically primitive Proconodontus muelleri Miller, 1969 from the late Cambrian and the more derived Panderodus equicostatus Rhodes, 1954 from the Silurian. Proposing that this extremely small sample is, however, representative for these taxa, we aim to describe in detail the growth of an element from each of these taxa in order to the test the following hypotheses: (1) Panderodus and Proconodontus processed hard food, which led to damage of their elements consistent with prey capture function; and (2) both genera shifted towards higher trophic levels during ontogeny. We employed backscatter electron (BSE) imaging, energy-dispersive X-ray spectroscopy (EDX) and synchrotron radiation X-ray tomographic microscopy (SRXTM) to identify growth increments, wear and damage surfaces, and the Sr/Ca ratio in bioapatite as a proxy for the trophic position. Using these data, we can identify whether they exhibit determinate or indeterminate growth and whether both species followed linear or allometric growth dynamics. Growth increments (27 in Pa. equicostatus and 58 in Pr. muelleri ) were formed in bundles of 4–7 increments in Pa. equicostatus and 7–9 in Pr. muelleri . We interpret the bundles as analogous to Retzius periodicity in vertebrate teeth. Based on applied optimal resource allocation models, internal periodicity might explain indeterminate growth in both species. They also allow us to interpret the almost linear growth of both individuals as an indicator that there was no size-dependent increase in mortality in the ecosystems where they lived e.g ., as would be the case in the presence of larger predators. Our findings show that periodic growth was present in early conodonts and preceded tissue repair in response to wear and damage. We found no microwear and the Sr/Ca ratio, and therefore the trophic position, did not change substantially during the lifetimes of either individual. Trophic ecology of coniform conodonts differed from the predatory and/or scavenger lifestyle documented for “complex” conodonts. We propose that conodonts adapted their life histories to top-down controlled ecosystems during the Nekton Revolution.
},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
<p> Conodonts were the first vertebrates to develop mineralized dental tools, known as elements. Recent research suggests that conodonts were macrophagous predators and/or scavengers but we do not know how this feeding habit emerged in the earliest coniform conodonts, since most studies focus on the derived, ‘complex’ conodonts. Previous modelling of element position and mechanical properties indicate they were capable of food processing. A direct test would be provided through evidence of <italic>in vivo</italic> element crown tissue damage or through <italic>in vivo</italic> incorporated chemical proxies for a shift in their trophic position during ontogeny. Here we focus on coniform elements from two conodont taxa, the phylogenetically primitive <italic>Proconodontus muelleri</italic> Miller, 1969 from the late Cambrian and the more derived <italic>Panderodus equicostatus</italic> Rhodes, 1954 from the Silurian. Proposing that this extremely small sample is, however, representative for these taxa, we aim to describe in detail the growth of an element from each of these taxa in order to the test the following hypotheses: (1) <italic>Panderodus</italic> and <italic>Proconodontus</italic> processed hard food, which led to damage of their elements consistent with prey capture function; and (2) both genera shifted towards higher trophic levels during ontogeny. We employed backscatter electron (BSE) imaging, energy-dispersive X-ray spectroscopy (EDX) and synchrotron radiation X-ray tomographic microscopy (SRXTM) to identify growth increments, wear and damage surfaces, and the Sr/Ca ratio in bioapatite as a proxy for the trophic position. Using these data, we can identify whether they exhibit determinate or indeterminate growth and whether both species followed linear or allometric growth dynamics. Growth increments (27 in <italic>Pa. equicostatus</italic> and 58 in <italic>Pr. muelleri</italic> ) were formed in bundles of 4–7 increments in <italic>Pa. equicostatus</italic> and 7–9 in <italic>Pr. muelleri</italic> . We interpret the bundles as analogous to Retzius periodicity in vertebrate teeth. Based on applied optimal resource allocation models, internal periodicity might explain indeterminate growth in both species. They also allow us to interpret the almost linear growth of both individuals as an indicator that there was no size-dependent increase in mortality in the ecosystems where they lived <italic>e.g</italic> ., as would be the case in the presence of larger predators. Our findings show that periodic growth was present in early conodonts and preceded tissue repair in response to wear and damage. We found no microwear and the Sr/Ca ratio, and therefore the trophic position, did not change substantially during the lifetimes of either individual. Trophic ecology of coniform conodonts differed from the predatory and/or scavenger lifestyle documented for “complex” conodonts. We propose that conodonts adapted their life histories to top-down controlled ecosystems during the Nekton Revolution. </p>
Czepiński, Łukasz; Dróżdż, Dawid; Szczygielski, Tomasz; Tałanda, Mateusz; Pawlak, Wojciech; Lewczuk, Antoni; Rytel, Adam; Sulej, Tomasz
An Upper Triassic Terrestrial Vertebrate Assemblage from the Forgotten Kocury Locality (Poland) with a New Aetosaur Taxon Journal Article
In: Journal of Vertebrate Paleontology, pp. e1898977, 2021.
@article{Czepinski2021,
title = {An Upper Triassic Terrestrial Vertebrate Assemblage from the Forgotten Kocury Locality (Poland) with a New Aetosaur Taxon},
author = {Łukasz Czepiński and Dawid Dróżdż and Tomasz Szczygielski and Mateusz Tałanda and Wojciech Pawlak and Antoni Lewczuk and Adam Rytel and Tomasz Sulej},
url = {https://doi.org/10.1080/02724634.2021.1898977},
doi = {10.1080/02724634.2021.1898977},
year = {2021},
date = {2021-04-14},
journal = {Journal of Vertebrate Paleontology},
pages = {e1898977},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Świś, Przemysław
A new Devonian species of the enigmatic Carboniferous conodont Dollymae Journal Article
In: Palaeoworld, 2021, ISSN: 1871-174X.
@article{SWIS2021,
title = {A new Devonian species of the enigmatic Carboniferous conodont Dollymae},
author = {Przemysław Świś},
url = {https://www.sciencedirect.com/science/article/pii/S1871174X21000251},
doi = {https://doi.org/10.1016/j.palwor.2021.03.003},
issn = {1871-174X},
year = {2021},
date = {2021-03-30},
journal = {Palaeoworld},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Dzik, Jerzy
Protaspis larva of an aglaspidid-like arthropod from the Ordovician of Siberia and its habitat Journal Article
In: Arthropod Structure & Development, vol. 61, pp. 101026, 2021, ISSN: 1467-8039.
@article{DZIK2021101026,
title = {Protaspis larva of an aglaspidid-like arthropod from the Ordovician of Siberia and its habitat},
author = {Jerzy Dzik},
url = {https://www.sciencedirect.com/science/article/pii/S1467803920301493},
doi = {https://doi.org/10.1016/j.asd.2020.101026},
issn = {1467-8039},
year = {2021},
date = {2021-01-01},
journal = {Arthropod Structure & Development},
volume = {61},
pages = {101026},
abstract = {A fossil larva lacking segmentation of the calcified carapace, closely resembling the trilobite protaspis, has been found associated with other skeletal elements of an angarocaridid Girardevia species in the mid Darriwilian of central Siberia. The presence of protaspis larvae in the angarocaridids, generally believed to represent a branch of the Aglaspidida, supports their proximity to trilobites and proves a low position on the arthropod phylogenetic tree but does not necessarily contradict the chelicerate affinity. The cephalic appendages of angarocaridids bore massive gnathobases with detachable spines, closely similar to those known in extant xiphosurans and in their probable Cambrian relatives. The stratigraphic succession of the angarocaridids, their phosphatized cuticle pieces being abundant in the Ordovician strata of Siberia, shows a gradual improvement of mechanical resistance of their carapaces, eventually resulting in a honeycomb structure. The associated benthic mollusc assemblage is dominated with the bellerophontids showing high mortality at metamorphosis and only the limpet-like Pterotheca, infaunal bivalves, and scaphopods being able to survive this in a substantial number. This suggests a strong selective pressure from predators equipped with well-skeletonised oral apparatuses able to crush mineralized body covers of their prey. Possibly, these were some of the associated conodonts of appropriate size and co-evolving towards their ability to crush more and more resistant cuticle. Less likely candidates for durophagy are endoceratid or orthoceratid cephalopods. Also the angarocaridids themselves, equipped with robust gnathobases of cephalic appendages, apparently predated on benthic shelly animals.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
A fossil larva lacking segmentation of the calcified carapace, closely resembling the trilobite protaspis, has been found associated with other skeletal elements of an angarocaridid Girardevia species in the mid Darriwilian of central Siberia. The presence of protaspis larvae in the angarocaridids, generally believed to represent a branch of the Aglaspidida, supports their proximity to trilobites and proves a low position on the arthropod phylogenetic tree but does not necessarily contradict the chelicerate affinity. The cephalic appendages of angarocaridids bore massive gnathobases with detachable spines, closely similar to those known in extant xiphosurans and in their probable Cambrian relatives. The stratigraphic succession of the angarocaridids, their phosphatized cuticle pieces being abundant in the Ordovician strata of Siberia, shows a gradual improvement of mechanical resistance of their carapaces, eventually resulting in a honeycomb structure. The associated benthic mollusc assemblage is dominated with the bellerophontids showing high mortality at metamorphosis and only the limpet-like Pterotheca, infaunal bivalves, and scaphopods being able to survive this in a substantial number. This suggests a strong selective pressure from predators equipped with well-skeletonised oral apparatuses able to crush mineralized body covers of their prey. Possibly, these were some of the associated conodonts of appropriate size and co-evolving towards their ability to crush more and more resistant cuticle. Less likely candidates for durophagy are endoceratid or orthoceratid cephalopods. Also the angarocaridids themselves, equipped with robust gnathobases of cephalic appendages, apparently predated on benthic shelly animals.
Sulej, Tomasz; Krzesiński, Grzegorz; Tałanda, Mateusz; Wolniewicz, Andrzej S.; Błażejowski, Błażej; Bonde, Niels; Gutowski, Piotr; Sienkiewicz, Maksymilian; Niedźwiedzki, Grzegorz
The earliest-known mammaliaform fossil from Greenland sheds light on origin of mammals Journal Article
In: Proceedings of the National Academy of Sciences, vol. 117, no. 43, pp. 26861-26867, 2020.
@article{Sulej26861,
title = {The earliest-known mammaliaform fossil from Greenland sheds light on origin of mammals},
author = {Tomasz Sulej and Grzegorz Krzesiński and Mateusz Tałanda and Andrzej S. Wolniewicz and Błażej Błażejowski and Niels Bonde and Piotr Gutowski and Maksymilian Sienkiewicz and Grzegorz Niedźwiedzki},
url = {https://www.pnas.org/content/117/43/26861},
doi = {https://doi.org/10.1073/pnas.2012437117 },
year = {2020},
date = {2020-10-27},
journal = {Proceedings of the National Academy of Sciences},
volume = {117},
number = {43},
pages = {26861-26867},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Sulej, Tomasz; Niedźwiedzki, Grzegorz; Tałanda, Mateusz; Dróżdż, Dawid; Hara, Ewa
A new early Late Triassic non-mammaliaform eucynodont from Poland Journal Article
In: Historical Biology, vol. 32, no. 1, pp. 80-92, 2020.
@article{doi:10.1080/08912963.2018.1471477,
title = {A new early Late Triassic non-mammaliaform eucynodont from Poland},
author = {Tomasz Sulej and Grzegorz Niedźwiedzki and Mateusz Tałanda and Dawid Dróżdż and Ewa Hara},
url = {https://doi.org/10.1080/08912963.2018.1471477},
doi = {10.1080/08912963.2018.1471477},
year = {2020},
date = {2020-01-01},
journal = {Historical Biology},
volume = {32},
number = {1},
pages = {80-92},
publisher = {Taylor & Francis},
abstract = {ABSTRACTBicuspid, tricuspid and tetracuspid postcanine teeth of a new non-mammaliaform eucynodont, Polonodon woznikiensis gen. et sp. nov. from the mid-late Carnian (early Late Triassic) of Woźniki clay-pit, Silesia (southern Poland) show incipient root division. They are similar to teeth of Dromatheriidae from the Carnian (early Late Triassic) to the Rhaetian (late Late Triassic) of Europe, India, and USA and the dentition of brasilodontids from the early Norian (mid Late Triassic) of Brazil. The P. woznikiensis teeth differ from those of the latter group mostly in the absence of cingulum. Some of the new fossils from Silesia provide the oldest Laurasian record of eucynodont teeth with the main cusp (a) anterior edge very long as the mesial cusp b is placed much lower than cusp c (distal). The contemporaneous Alemoatherium huebneri, from Gondwana, had similar postcanines. The findings from Poland indicate that this postcanine morphology was present in non-mammaliaform cynodonts from both hemispheres as early as the mid-late Carnian. The distal end of the humerus from the same locality is also described.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
ABSTRACTBicuspid, tricuspid and tetracuspid postcanine teeth of a new non-mammaliaform eucynodont, Polonodon woznikiensis gen. et sp. nov. from the mid-late Carnian (early Late Triassic) of Woźniki clay-pit, Silesia (southern Poland) show incipient root division. They are similar to teeth of Dromatheriidae from the Carnian (early Late Triassic) to the Rhaetian (late Late Triassic) of Europe, India, and USA and the dentition of brasilodontids from the early Norian (mid Late Triassic) of Brazil. The P. woznikiensis teeth differ from those of the latter group mostly in the absence of cingulum. Some of the new fossils from Silesia provide the oldest Laurasian record of eucynodont teeth with the main cusp (a) anterior edge very long as the mesial cusp b is placed much lower than cusp c (distal). The contemporaneous Alemoatherium huebneri, from Gondwana, had similar postcanines. The findings from Poland indicate that this postcanine morphology was present in non-mammaliaform cynodonts from both hemispheres as early as the mid-late Carnian. The distal end of the humerus from the same locality is also described.
Pawlak, Wojciech; Tałanda, Mateusz; Sulej, Tomasz; Niedźwiedzki, Grzegorz
Dipnoan from the Upper Triassic of East Greenland and remarks about palaeobiogeography of Ptychoceratodus Journal Article
In: Acta Palaeontologica Polonica, vol. 65, pp. 561-574, 2020.
@article{Pawlak2020DipnoanFT,
title = {Dipnoan from the Upper Triassic of East Greenland and remarks about palaeobiogeography of Ptychoceratodus},
author = {Wojciech Pawlak and Mateusz Tałanda and Tomasz Sulej and Grzegorz Niedźwiedzki},
year = {2020},
date = {2020-01-01},
urldate = {2020-01-01},
journal = {Acta Palaeontologica Polonica},
volume = {65},
pages = {561-574},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Pindakiewicz, Maciej; Tałanda, Mateusz; Sulej, Tomasz; Niedźwiedzki, Grzegorz; Sennikov, A G; Bakayev, A; Bulanov, V V; Golubev, V; Minikh, A V
Feeding convergence among ray-finned fishes: teeth of the herbivorous actinopterygians from the latest Permian of East European Platform, Russia Journal Article
In: Acta Palaeontologica Polonica, vol. 65, no. 1, pp. 71–79, 2020.
@article{Pindakiewicz2020FeedingCA,
title = {Feeding convergence among ray-finned fishes: teeth of the herbivorous actinopterygians from the latest Permian of East European Platform, Russia},
author = {Maciej Pindakiewicz and Mateusz Tałanda and Tomasz Sulej and Grzegorz Niedźwiedzki and A G Sennikov and A Bakayev and V V Bulanov and V Golubev and A V Minikh},
year = {2020},
date = {2020-01-01},
journal = {Acta Palaeontologica Polonica},
volume = {65},
number = {1},
pages = {71--79},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Piechowski, Rafał; Tałanda, Mateusz
The locomotor musculature and posture of the early dinosauriform Silesaurus opolensis provides a new look into the evolution of Dinosauromorpha Journal Article
In: Journal of Anatomy, vol. 236, no. 6, pp. 1044-1100, 2020.
@article{https://doi.org/10.1111/joa.13155,
title = {The locomotor musculature and posture of the early dinosauriform Silesaurus opolensis provides a new look into the evolution of Dinosauromorpha},
author = {Rafał Piechowski and Mateusz Tałanda},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/joa.13155},
doi = {https://doi.org/10.1111/joa.13155},
year = {2020},
date = {2020-01-01},
journal = {Journal of Anatomy},
volume = {236},
number = {6},
pages = {1044-1100},
abstract = {Abstract It is widely accepted that ornithodirans (bird lineage) and some pseudosuchians (crocodilian lineage) achieved fully erect limb posture in different ways. Ornithodirans have buttress-erected hindlimbs, while some advanced pseudosuchians have pillar-erected hindlimbs. Analysis of the musculoskeletal apparatus of the early dinosauriform Silesaurus opolensis challenges this view. This ornithodiran had pillar-erected hindlimbs like some pseudosuchians. This condition could be autapomorphic or represents a transitional state between adductor-controlled limb posture of early dinosauromorphs and the buttress-erected hindlimbs of dinosaurs. This sequence of changes is supported by Triassic tracks left by animals of the dinosaurian lineage. It was associated with the strong development of knee flexors and extensors. Furthermore, the forelimbs of Silesaurus were fully erect, analogously to those of early sauropods. Members of both lineages reduced the muscles related to the protraction, retraction and bending of the limb. They used forelimbs more as a body support and less for propulsion. A similar scapula and humerus construction can be found in the Lagerpetidae and Lewisuchus, suggesting that long, slender, fully erected forelimbs are primitive for all Dinosauromorpha, not just Silesauridae. Early dinosaurs redeveloped several muscle attachments on the forelimb, probably in relation to bipedality.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Abstract It is widely accepted that ornithodirans (bird lineage) and some pseudosuchians (crocodilian lineage) achieved fully erect limb posture in different ways. Ornithodirans have buttress-erected hindlimbs, while some advanced pseudosuchians have pillar-erected hindlimbs. Analysis of the musculoskeletal apparatus of the early dinosauriform Silesaurus opolensis challenges this view. This ornithodiran had pillar-erected hindlimbs like some pseudosuchians. This condition could be autapomorphic or represents a transitional state between adductor-controlled limb posture of early dinosauromorphs and the buttress-erected hindlimbs of dinosaurs. This sequence of changes is supported by Triassic tracks left by animals of the dinosaurian lineage. It was associated with the strong development of knee flexors and extensors. Furthermore, the forelimbs of Silesaurus were fully erect, analogously to those of early sauropods. Members of both lineages reduced the muscles related to the protraction, retraction and bending of the limb. They used forelimbs more as a body support and less for propulsion. A similar scapula and humerus construction can be found in the Lagerpetidae and Lewisuchus, suggesting that long, slender, fully erected forelimbs are primitive for all Dinosauromorpha, not just Silesauridae. Early dinosaurs redeveloped several muscle attachments on the forelimb, probably in relation to bipedality.
Świś, Przemysław; Broda, Krzysztof; Duda, Piotr; Dróżdż, Dawid; Łazuka, Anna
The early Famennian (Late Devonian) conodonts natural assemblages from Holy Cross Mountains (Poland) Journal Article
In: Historical Biology, vol. 0, no. 0, pp. 1-8, 2020.
@article{doi:10.1080/08912963.2020.1719085,
title = {The early Famennian (Late Devonian) conodonts natural assemblages from Holy Cross Mountains (Poland)},
author = {Przemysław Świś and Krzysztof Broda and Piotr Duda and Dawid Dróżdż and Anna Łazuka},
url = {https://doi.org/10.1080/08912963.2020.1719085},
doi = {10.1080/08912963.2020.1719085},
year = {2020},
date = {2020-01-01},
journal = {Historical Biology},
volume = {0},
number = {0},
pages = {1-8},
publisher = {Taylor & Francis},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Świś, Przemysław; Dzik, Jerzy
The oral apparatus composition of the Early Carboniferous elictognathid conodont 'Siphonodella' Journal Article
In: Lethaia, 2020, (Publisher: Wiley).
@article{swis_oral_2020,
title = {The oral apparatus composition of the Early Carboniferous elictognathid conodont 'Siphonodella'},
author = {Przemysław Świś and Jerzy Dzik},
url = {https://doi.org/10.1111%2Flet.12406},
doi = {10.1111/let.12406},
year = {2020},
date = {2020-01-01},
journal = {Lethaia},
note = {Publisher: Wiley},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Czepiński, Łukasz
New protoceratopsid specimens improve the age correlation of the Upper Cretaceous Gobi Desert strata Journal Article
In: Acta Palaeontologica Polonica, vol. 65, 2020.
@article{Czepiski2020NewPS,
title = {New protoceratopsid specimens improve the age correlation of the Upper Cretaceous Gobi Desert strata},
author = {Łukasz Czepiński},
year = {2020},
date = {2020-01-01},
journal = {Acta Palaeontologica Polonica},
volume = {65},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Czepiński, Łukasz
Ontogeny and variation of a protoceratopsid dinosaur Bagaceratops rozhdestvenskyi from the Late Cretaceous of the Gobi Desert Journal Article
In: Historical Biology, vol. 32, no. 10, pp. 1394–1421, 2020.
@article{doi:10.1080/08912963.2019.1593404,
title = {Ontogeny and variation of a protoceratopsid dinosaur Bagaceratops rozhdestvenskyi from the Late Cretaceous of the Gobi Desert},
author = {Łukasz Czepiński},
url = {https://doi.org/10.1080/08912963.2019.1593404},
doi = {10.1080/08912963.2019.1593404},
year = {2020},
date = {2020-01-01},
journal = {Historical Biology},
volume = {32},
number = {10},
pages = {1394--1421},
publisher = {Taylor & Francis},
abstract = {Bagaceratops rozhdestvenskyi is a ceratopsian dinosaur from the Late Cretaceous Baruungoyot Formation of the Gobi Desert, closely related to Protoceratops spp. Several Bag. rozhdestvenskyi skulls demonstrate a wide range of variation in their morphology and size. Here I argue that the observed variability is most likely of intraspecific nature. Specimens classified in a few allegedly distinct species from the same or near-contemporary sediments, namely Gobiceratops minutus, Lamaceratops tereschenkoi and Platyceratops tatarinovi from Baruungoyot Formation, and Magnirostris dodsoni from Bayan Mandahu, are younger subjective synonyms of Bag. rozhdestvenskyi. They plausibly represent an ontogenetic series within the latter. Breviceratops kozlowskiiis a distinct taxon. The evolutionary relationships within Protoceratopsidae are complicated by the mosaic distribution of plesiomorphic and derived features in distinct species. I suggest that taxa distribution and observed changes in morphology are an evidence for the ancestral position of Protoceratops andrewsi among protoceratopsids. It implies possible temporary separation between the geological formations of the Gobi Desert yielding distinct protoceratopsid species. The novel evolutionary scenario suggests number of convergences that occurred in Protoceratopsidae and Ceratopsoidea (reduction of the premaxillary dentition, fusion of nasals, development of the accessory antorbital fenestra). Present study reveals the significance of the intraspecific and ontogenetic variation in the study of the neoceratopsian taxonomy.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Bagaceratops rozhdestvenskyi is a ceratopsian dinosaur from the Late Cretaceous Baruungoyot Formation of the Gobi Desert, closely related to Protoceratops spp. Several Bag. rozhdestvenskyi skulls demonstrate a wide range of variation in their morphology and size. Here I argue that the observed variability is most likely of intraspecific nature. Specimens classified in a few allegedly distinct species from the same or near-contemporary sediments, namely Gobiceratops minutus, Lamaceratops tereschenkoi and Platyceratops tatarinovi from Baruungoyot Formation, and Magnirostris dodsoni from Bayan Mandahu, are younger subjective synonyms of Bag. rozhdestvenskyi. They plausibly represent an ontogenetic series within the latter. Breviceratops kozlowskiiis a distinct taxon. The evolutionary relationships within Protoceratopsidae are complicated by the mosaic distribution of plesiomorphic and derived features in distinct species. I suggest that taxa distribution and observed changes in morphology are an evidence for the ancestral position of Protoceratops andrewsi among protoceratopsids. It implies possible temporary separation between the geological formations of the Gobi Desert yielding distinct protoceratopsid species. The novel evolutionary scenario suggests number of convergences that occurred in Protoceratopsidae and Ceratopsoidea (reduction of the premaxillary dentition, fusion of nasals, development of the accessory antorbital fenestra). Present study reveals the significance of the intraspecific and ontogenetic variation in the study of the neoceratopsian taxonomy.
Dzik, Jerzy
Decline in diversity of early Palaeozoic loosely coiled gastropod protoconchs Journal Article
In: Lethaia, vol. 53, no. 1, pp. 32–46, 2020.
@article{dzik_decline_2020,
title = {Decline in diversity of early Palaeozoic loosely coiled gastropod protoconchs},
author = {Jerzy Dzik},
year = {2020},
date = {2020-01-01},
journal = {Lethaia},
volume = {53},
number = {1},
pages = {32--46},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Dzik, Jerzy
Ordovician conodonts and the Tornquist Lineament Journal Article
In: Palaeogeography, Palaeoclimatology, Palaeoecology, vol. 549, 2020.
@article{dzik_ordovician_2020,
title = {Ordovician conodonts and the Tornquist Lineament},
author = {Jerzy Dzik},
year = {2020},
date = {2020-01-01},
journal = {Palaeogeography, Palaeoclimatology, Palaeoecology},
volume = {549},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Dzik, Jerzy
Variability of conch morphology in a cephalopod species from the Cambrian to Ordovician transition strata of Siberia Journal Article
In: Acta Palaeontologica Polonica, vol. 65, pp. 149–165, 2020, (Publisher: Polska Akademia Nauk Instytut Paleobiologii (Institute of Paleobiology, Polish Academy of Sciences)).
@article{dzik_variability_2020,
title = {Variability of conch morphology in a cephalopod species from the Cambrian to Ordovician transition strata of Siberia},
author = {Jerzy Dzik},
url = {https://doi.org/10.4202%2Fapp.00674.2019},
doi = {10.4202/app.00674.2019},
year = {2020},
date = {2020-01-01},
journal = {Acta Palaeontologica Polonica},
volume = {65},
pages = {149--165},
note = {Publisher: Polska Akademia Nauk Instytut Paleobiologii (Institute of Paleobiology, Polish Academy of Sciences)},
keywords = {},
pubstate = {published},
tppubtype = {article}
}