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Page 17 of 19, showing 20 record(s) out of 366 total

Revision des faunes de vertébrés du site de Provenchères-sur-Meuse (Trias terminal, Nord-Est de la France)
Gilles Cuny Logo
Published online: 14/06/1995

Keywords: amphibians; Fishes; Reptiles; Rhetian; Triassic

https://doi.org/10.18563/pv.24.1-2.101-134

  Abstract

    Revision of ancient collections and study of new material from Provenchères-sur-Meuse (Rhaetian) lead to signíficant changes in the faunal list of this site. This bring to us important information about the effect of the rhaetian transgression on the evolution of the faunas at this period of time. However, study of
    vertebrate microremains is always difficult and some points remain obscure, like the origin of the prosauropods which yield some remains at Provenchères-sur-Meuse and the survival in Europe during the Rhaetian of temnospondyl arnphibians different from the Plagiosauridae.

      


  PV article infos

Published in Vol. 24, Fasc. 1-2 (1995)

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Otolithes de poissons du Pliocène inférieur de Papiol, près de Barcelone.
Dirk Nolf, Ramon Mané and Agusti Lopez
Published online: 15/09/1998

Keywords: Catalonia; otoliths; Pliocene; Spain; teleosts

https://doi.org/10.18563/pv.27.1-2.1-17

  Abstract

    The Zanclian marls from Papiol provided otoliths belonging to 53 teleost taxa; nine of those are new for the Mediterranean Pliocene. The association reflects a bathymetry between 150 and 350 m, but it is likely that such depths only existed at the initial stage of flooding of the Llobregat bay. A compilation of the available data for the whole Mediterranean realm at Zanclian time provided a list of 163 taxa, of which 105 could be identified at species level. This last group provides the most useful data for evaluating the composition and affinities of the Mediterranean Zanclian fauna, which appears to be significantly different from the Recent Mediterranean fauna. The Zanclian fauna counts 68 % of Recent species: 12,5 % were already represented in the Mediterranean Miocene, 37 % appeared there at the Zanclian, and 18 % are extra-Mediterranean today. This last group is essentially composed by oceanic fishes, living in the warm parts of the Atlantic and Indo-Pacific Oceans. It is evident that a non neglectable number of Recent species only penetrated very recently in the Mediterranean, which stresses the differences between the more oceanic Zanclian Mediterranean fauna and the present one.


      


  PV article infos

Published in Vol. 27, Fasc. 1-2 (1998)

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Octodontid-like Echimyidae (Rodentia) : an upper Miocene episode in the radiation of the family
Diego H. Verzi Logo, Maria G. Vucetich Logo and Claudia I. Montalvo Logo
Published online: 20/05/1994

Keywords: Argentina; Echimyidae; Miocene; New taxa; Rodentia; South America

https://doi.org/10.18563/pv.23.1-4.199-210

  Abstract

    Reigechimys octodontiformis gen. et sp. novo and R. plesiodon sp. novo are described. They represent the frrst record of the family Echimyidae for the Cerro Azul Formation (Huayquerian Age, Late Upper Miocene) at La Pampa Province, central Argentina. Both species have hypsodont cheek teeth with an eight-shaped occlusal design. This dental morphology represents a noticeable case of convergence to octodontids and indicates that these echimyids inhabited open environments. 


  PV article infos

Published in Vol. 23, Fasc. 1-4 (1994)

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Diversity of triconodont mammals from the early Cretaceous of North Africa-affinities of the Amphilestids
Denise Sigogneau-Russell
Published online: 15/10/2003

Keywords: amphilestines; Early Cretaceous; gobiconodontines; North Africa; Teeth; triconodonts

https://doi.org/10.18563/pv.32.1

  Abstract

    The mammalian fauna (represented only by isolated teeth) from the early Cretaceous of Morocco includes a number of non-'therian' specimens, characterized by the antero-posterior alignement of the main molar cusps. This assemblage is very heterogenous, including forms (among them Gobiconodon palaios sp. nov.) that can be related to Laurasian triconodonts and several forms so far known only in this part of Gondwana (among them Kryptotherium polysphenos gen. et sp. nov.). The latter, in particular, exemplifies the diversity of the mammalian dental morphology in the Mesozoic, often largely underestimated. In the last part of this paper, the 'therian' affinity of the 'amphilestids' is discussed, on the basis of the arrangement of molar cusps, the interlocking mechanism and the occlusal pattem. 


  PV article infos

Published in Vol. 32, Fasc. 1 (2003)

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La région des phosphorites du Quercy
A. Cavaillé
Published online: 15/11/1974

Keywords: Quercy Phosphorites

https://doi.org/10.18563/pv.6.1-2.5-19

  Abstract

    L'exploitation des phosphates s'est produite surtout de 1890 à 1914 de Saint-Antonin à Cajarc, sur le Causse de Limogne, dont l'histoire géologique et morphologique peut expliquer les conditions de gisement du minerai, et aussi la découverte des nombreux, variés et beaux fossiles qu'on a extrait des poches en même temps que la phosphorite. Le Causse de Limogne est le nom donné par les géographes au plateau calcaire, faisant partie des Causses du Quercy, et compris entre la vallée du Lot au Nord et celle de "Aveyron au Sud". En fait, le nom de "causse" désigne localement un terroir, un paysage, à sous-sol de calcaire, à sol peu épais, qui s'oppose aux sols argileux des « terreforts » et aux sols légers et profonds des "boulbènes". Chaque communauté agricole distinguait ainsi son causse, par exemple le causse de Caylus, le causse de Limogne ou le causse de Cajarc. C'est par extension que l'appellation Causse de Limogne désigne tout un petit pays. La présence des poches à phosphate déborde un peu vers le Nord la vallée du Lot, et vers l'Est le Causse de Limogne proprement dit (Causse de Villeneuve).   


  PV article infos

Published in Vol. 06, Fasc. 1-2 (1974)

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The lower Miocene artiodactyls of Tagai bay, Olhon island, lake Baikal (Russia)
Inesa Vislobokova Logo
Published online: 20/05/1994

Keywords: Artiodactyls; Mammals; Miocene; Siberia

https://doi.org/10.18563/pv.23.1-4.177-197

  Abstract

    The mammalian fauna of the Tagai locality of Olhon Island in Lake Baikal contains six artiodactyls:
    Amphitragulus boulangeri, Lagomeryx parvulus, Stephanocemas sp., Palaeomeryx kaupi, Orygotherium aff. escheri, and Brachyodus intermedius. They are reported from Eastern Siberia for the first time. A description of teeth and limb-bones are given. An analysis of the systematic composition of the Tagai fauna allows it to be correlated with European faunas of the second part of the Early Miocene (Orleanian, MN 3-4) and permit suggestion of the existance of a united European-Siberian zoogeographical sub-area in the middle latitudes of Eurasia at that time. 


  PV article infos

Published in Vol. 23, Fasc. 1-4 (1994)

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Analyse d'ouvrage: “A.G. SMITH, D.G. SMITH & B.M. FUNNELL: Atlas of Mesozoic and Cenozoic coastlines (1995)”
Jacques Michaux
Published online: 18/03/1996

Keywords: Atlas; Book review; Cenozoic; Coastlines; Mesozoic

https://doi.org/10.18563/pv.25.1.56

  Abstract

    ATLAS OF MESOZOIC AND CENOZOIC COASTLINES, par Alan G. SMITH, David G. SMITH & Brian M. FUNNELL, 1995. Cambridge University Press, 99 p., 31 cartes, 3 tab!., 2 fig. ISBN 0-521-45155-8.

    L' "Atlas of Mesozoic and Cenozoic coastlines" succède avec bonheur aux "Mesozoic and Cenozoic paleocontinental maps" de Smith & Briden, publié en 1977. 


  PV article infos

Published in Vol. 25, Fasc. 1 (1996)

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Contributions à l'étude du gisement Miocène supérieur de Montredon (Hérault). Les grands mammifères. 5 - Les périssodactyles Equidae
Véra Eisenmann
Published online: 15/11/1988

Keywords: Equidae; Hipparion; Late Vallesian; Mammalia; Montredon; Perissodactyla

https://doi.org/10.18563/pv.18.ext.65-96

  Abstract

    Revision of the hipparion material from Montredon, including newly excavated and other unpublished specimens brings evidence of specific heterogeneity.
    A fragmentary very small MC III seems very close to H. macedonicum from the upper Vallesian of Ravin de la Pluie, Greece. In that same site was also found a large hipparion.
    Most of the Montredon material is referred to H. depereti. This species associates characters usually found in Vallesian hipparions (highly plicated upper cheek teeth, deep vestíbular grooves on the lower cheek teeth, robust metapodials) with characters more frequent in Turolian forms (middle size, lack of confluence in the upper premolar fossettes, lack of ectostylids on the adult lower cheek teeth, well developped keel on the MC III, facette for the 2nd cuneiform present on all MT III). H. depereti shares some of these characters with the Spanish and Portuguese hipparions transítional between the Vallesian and the Turolian (Masia del Barbo, Azambujeira) but is not identícal to any of them. The upper Vallesian hipparion material from Diavata, Greece, probably belongs to H. depereti but not the large hipparion rests from Ravin de la Pluie.
    Thus, Montredon and Ravin de la Pluie may well share the same small species, H. macedonicum, but they differ in the associated one: middle-sized H. depereti at Montredon, large-sized H. primigenium at Ravin de la Pluie. Both sites, however, give evidence of small hipparions during the Vallesian, coexisting with other larger species.
    The present paper also proposes an adaptation of the Kiesewalter's indices that calculates the height at the withers using the metapodial length, and discusses indices proposed by Gromova and by Sen et al. to express the relative development of the metapodial keel. 


  PV article infos

Published in Vol. 18, Ext (1988)

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Sur le statut taxonomique de Myotis KAUP 1829 (Mammalia, Chiroptera).
Henri Menu
Published online: 15/12/1988

Keywords: Myotis; taxonomy

https://doi.org/10.18563/pv.18.4.263

  Abstract

    Suite à la récente publication d'une révision systématique des Chiroptera Vespertilioninae, conduite sur la base des morphologies dentaires comparées (Menu 1987), une remarque bienveillante du Dr. V. Aellen (Muséum d'Histoire Naturelle de Genève) a attiré l'attention de l'auteur sur un point précis du Code International de Nomenclature Zoologique. 


  PV article infos

Published in Vol. 18, Fasc. 4 (1988)

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The endocranial cast and encephalization quotient of Ptilodus (Multituberculata, Mammalia)
David W. Krause Logo and Zofia Kielan-Jaworowska Logo
Published online: 11/02/1993

Keywords: encephaIization quotient; endocranial cast; Montana; Multituberculata; olfactory bulbs; Paleocene; Ptilodus

https://doi.org/10.18563/pv.22.2-3.99-112

  Abstract

    Simpson (1937a) reconstructed the brain of the Paleocene multituberculate Ptilodus as having the olfactory bulbs widest anteriorly, an unusual condition among mammals. Slight preparation and reexamination of the endocast specimens of Ptilodus reveals that the olfactory bulbs in fact taper anteriorly, as in the recently-described endocranial casts of three multituberculate species from the Late Cretaceous of Asia, and as in those of other mammals. The brain of Ptilodus was therefore essentially of the same general pattem as in other multituberculates. Ptilodus differs, however, in having the vermis more deeply inserted between the cerebral hemispheres. Other details concerning the endocast morphology of Ptilodus are clarified.

    The encephalization quotient (EQ) of Ptilodus is recalculated from revised estimates of both endocranial volume and body mass to fall somewhere within a broad range of values; from 0.41 to 0.62 if the olfactory bulbs are included and from 0.37 to 0.55 if they are not. In any case, the relative brain size of Ptilodus is roughly equivalent to that of Chulsanbaatar, the only other multituberculate for which EQ has been calculated, but considerably smaller than that of an average extant mammnal. 


  PV article infos

Published in Vol. 22, Fasc. 2-3 (1993)

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Archosauriform teeth from the upper Triassic of Saint Nicolas-de-Port (Northeastern France).
Pascal Godefroit Logo and Gilles Cuny Logo
Published online: 15/12/1997

Keywords: Archosauriforms; Graoullyodon hacheti; Saint-Nicolas-de-port; Teeth; Upper Triassic

https://doi.org/10.18563/pv.26.1-4.1-34

  Abstract

    The Late Triassic locality of Saint-Nicolas-de-Port (Meurthe-et-Moselle, France) has yielded numerous isolated teeth belonging to archosauriform reptiles. The following tooth groups can be identified: heterodont phytosaurs, the pterosaur Eudimorphodon, the prosauropod dinosaur Plateosaurus, three types of putative ornithischian teeth and 13 types of carnivorous Archosauriformes indet. Apparent venom-conducting teeth belonging to a new taxon of ?Archosauriformes (Graoullyodon hacheti nov. gen. nov. sp.) are also described. From a palaeogeographical point of view, the ornithischian teeth from Saint-Nicolas-de-Port (if their attribution is confirmed) are the oldest fossils of this group in Europe. The biostratigraphic distribution of the tooth forms mostly suggests a Late Norian or Early Rhaetian (depending on current interpretations) age of the deposits, but do not provide more precisions than fossils previously described from the area. The dietary habits and, consequently, the palaeoecological relationships of the different vertebrate groups discovered at Saint-Nicolas-de-Port are tentatively established: the ornithischian and prosauropod teeth reflect a herbivorous diet, whereas the other archosauriform teeth are probably from camivores or omnivores.

      


  PV article infos

Published in Vol. 26, Fasc. 1-4 (1997)

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The paramyid rodent Ailuravus from the middle and late Eocene of Europe, and its relationships
Albert E. Wood
Published online: 15/05/1976

Keywords: Ailuravinae; Rodentia

https://doi.org/10.18563/pv.7.1-2.117-149

  Abstract

    The complex taxonomic history of the paramyid rodent genus Ailuravus is reviewed. It has been described as Hyracotherium, as a creodont carnivore and as a lemuroid primate - errors at the ordínal level that are most unusual for a rodent. The genus is a member of the poorly known subfamily Ailuravinae, probably derived from some European Early Eocene species of Paramys. Aíluravus was a large arboreal paramyid with highly rugose cheek teeth, very well developed hypocone, and a remarkably weak lower incisor. It was tropical to subtropical. Three named species are recognized, A. macrurus from the Lutetian of Messel; the genotype, A. picteti, from Egerkingen, Buchsweiler and the Geiseltal, slightly later in the Lutetian; and A. stehlinschaubi, new name, from the Bartonian of Mormont-Eclépens and Robiac. One or more unnamed species are present in the Ypresian of Cuis. The species are close to a phyletic sequence. No later representatives of the genus are known. The late Eocene to earliest Oligocene North American paramyid Mytonomys, whose relationships have been obscure, is tentatively referred to the Ailuravinae. 


  PV article infos

Published in Vol. 07, Fasc. 1-2 (1976)

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Origins of avian reproduction: answers and questionsfrom dinosaurs.
David J. Varricchio Logo and Frankie D. Jackson
Published online: 15/12/2003

Keywords: Avian reproduction; clutch; dinosaurs; egg size; nests; oviducts; parental care

https://doi.org/10.18563/pv.32.2-4.149-169

  Abstract

    The reproductive biology of living birds differs dramatically from that of other extant vertebrates. Distinctive features common to most birds include a single ovary and oviduct, production of one egg at daily or greater intervals, incubation by brooding and extensive parental care. The prevalence of male parental care is most exceptional among living amniotes. A variety of hypotheses exist to explain the origin of avian reproduction. Central to these models are proposed transitions from a condition of no care to maternal, paternal or biparental care systems. These evolutionary models incorporate a number of features potentially preservable or inferable from the fossil record (integument, skeletal adaptations for flight, egg and clutch size, nest form, hatchling developmental stage, the number and function of oviducts, and the mode of egg incubation). Increasing availability of data on dinosaur reproduction provides a means of assessing these hypotheses with fossil evidence. We compare dinosaur data to a selection of models that emphasize maternal, paternal or biparental care. Despite some congruence with dinosaur features, no single model on the evolution of avian reproduction conforms fully to the fossil record, and the ancestral parental care system of birds remains ambiguous. Further investigation into dinosaur parental care, nest structures, clutch geometry, egg-pairing, eggshell porosity, and embryo identification may eventually resolve these issues.  


  PV article infos

Published in Vol. 32, Fasc. 2-4 (2003)

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Second international symposium on Dinosaur, Eggs and Babies (Montpellier-Aix-en-Provence, 25-29 Août 2003).
Monique Vianey-Liaud Logo
Published online: 15/12/2003

Keywords: amniotic eggshells; dinosaurs

https://doi.org/10.18563/pv.32.2-4.71-76

  Abstract

    Le premier Symposium International sur les ceufs de dinosaures et leurs petits a connu un francs succès, à Isona, en Catalogne (Espagne) en 1999. I1 faisait suite à la publication en 1994 d'un premier ouvrage "Dinosaurs eggs and babies" édité par K. Carpenter, K. Hirsch et J. Homer. Entre 1994 et 1999, les nouvelles découvertes ont augmenté significativement, notamment celles d'ceufs embryonnés, et le nombre de chercheurs impliqués dans ce domaine a accompagné cet accroissement. Jusque là, l'étude de ces objets, les coquilles d'ceufs, est restée longtemps marginale, faute d'une méthodologie scientifique appropriée. 


  PV article infos

Published in Vol. 32, Fasc. 2-4 (2003)

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La morphologie dentaire des Thalattosuchia (Crocodylia, Mesosuchia).
Patrick Vignaud Logo
Published online: 15/12/1997

Keywords: Dental morphology; Dental types; feeding habits.; Jurassic; Metriorhynchidae; Systematics; Teleosauridae; Thalattosuchia

https://doi.org/10.18563/pv.26.1-4.35-59

  Abstract

    The tooth morphology of the Thalattosuchia (marine crocodilians from the Jurassic and the Early Cretaceous) is analysed. The Callovian from Poitou and the Kimmeridgian from Quercy have yielded many remains of Metriorhynchus, Steneosaurus and Machimosaurus. These remains allow us to study the variations of tooth morphology during ontogenic growth, tooth replacement and the location of the teeth. We have defined different tooth types for these genera. In Metriorhynchus, the two tooth types defined do not coincide with the two groups recognized in the Callovian (broad-skulled and narrow-skulled metriorhynchids) but reflect the prey preferences of these forms. In Steneosaurus and Machimosaurus the five tooth types deñned are in agreement with the main taxa known from the Bathonian to the Early Cretaceous. This study allows to precise the function and the prey preference of the Thalattosuchia during the Jurassic and the Early Cretaceous.

      


  PV article infos

Published in Vol. 26, Fasc. 1-4 (1997)

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Die Referenzfauna des Geiseltalium, MP levels 11 bis 13 (Mitteleozan, Lutetium)
Hartmut Haubold
Published online: 04/12/1989

Keywords: Eocene; Geiseltal; Land mammal ages; Mammalian reference levels

https://doi.org/10.18563/pv.19.3.81-93

  Abstract

    The Middle Eocene Fossillägerstätte of the Geiseltal lignite beds near Halle/S. (German Democratic Republic) is the reference locality of the European land mammal age Geiseltalian and of the Mammalian Paleogene reference levels MP 11 - MP 13. Due to this importance a reinvestigation is given of the lithostratigraphical development of the Geiseltal beds and of their vertebrate sites. The last are genetically related to the southwest border of the Geiseltal depression and the influx of carbonate-rich waters. The geographical distribution and stratigraphical position of the fossiliferous sites depends on subrosive and tectonically controlled distribution of coal seams. The geological factors and the known stratigraphical guide of some mammalian species suggest corrections of the age of some sites. Four of the alltogether five coal bearing phases contain the 35 sites with mammalian remains. By the distribution of the around 69 mammal species are characterized, with 5 faunal steps ranging from MP 11 to MP 14 or over the Geiseltalian up to the Lower Robiacian. Well distant are the faunas of MP 11 and MP 12. Beginning with MP 12 up to MP 13/14, the fossil record is very frequent by 27 sites. This evidence coincides somewhat more with the concept of land mammal ages compared to that of the punctual mammalian reference levels. 


  PV article infos

Published in Vol. 19, Fasc. 3 (1989)

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Book review : Dr. Robert R. REISZ, 1986.  Encyclopedia of Paleoherpetology,  Volume: 17A: Pelycosauria.
Jean-Yves Crochet
Published online: 20/06/1987

Keywords: Book review; Paleoherpetology

https://doi.org/10.18563/pv.17.2.75-76

  Abstract

    L’Encyclopedia of Paleoherpetology, Part 17A : Pelycosauria de Robert R. Reisz (1986) offre une synthèse complète des synapsides les plus primitifs et les plus anciens, essentiels pour comprendre l’évolution précoce de ce groupe majeur de vertébrés. L’ouvrage commence par un historique, suivi d’une analyse ostéologique détaillée du crâne, du squelette axial et appendiculaire. 


  PV article infos

Published in Vol. 17, Fasc. 2 (1987)

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Palaeotis weigelti restudied : a small middle Eocene Ostrich (Aves : Struthioniformes)
Peter Houde Logo and Hartmut Haubold
Published online: 20/06/1987

Keywords: Aves; Central Europe; Middle Eocene; Palaeotis; Struthioniformes

https://doi.org/10.18563/pv.17.2.27-42

  Abstract

    Palaeotis weigelti, from the Middle Eocene of central Europe, is a flightless, paleognathous bird. It appears to be a member of the ostrich lineage on the basis of trivial derived characters. It is a very primitive ratite, however, and does not possess any of the highly specialized cursorial adaptations that characterize the modern steppe -and savanna- dwelling ostriches. 


  PV article infos

Published in Vol. 17, Fasc. 2 (1987)

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Evolution et extinction des reptiles marins au cours du Mésozoïque.
Nathalie Bardet Logo
Published online: 02/10/1995

Keywords: Crocodiles; evolution; Extinctions; faunal assemblages; Helveticosaurs; Hupehsuchians; Ichthyoaurs; lizards; Marine Reptiles; Mesozoic; Nothosaurs; Pachypleurosaurs; Placodonts; Plesiosaurs; Snakes; Thalattosaurs; Turnovers; Turtles

https://doi.org/10.18563/pv.24.3-4.177-283

  Abstract

    An interpretation of the marine reptile fossil record, based on the existing litterature and complemented by the review of ancient collections and the study of new material, permits a better understanding of Mesozoic marine ecosystems. An inventory of the marine reptiles known from the Lower Triassic to the Paleocene is presented: 46 families, about 200 genera and 400 species have been recorded. This data base includes commentaries about systematics, stratigraphical ranges and geographical distribution of taxa. Marine reptiles include a mosaic of not necessarily closely related groups: ichthyosaurs, thalattosaurs, hupehsuchians, pachypleurosaurs, placodonts, nothosaurs, plesiosaurs, pliosaurs but also crocodiles, lizards, snakes, turtles. The diversity studies reveal that the fossil record of marine reptiles has been punctuated by two mass extinctions, during the Middle-Upper Triassic transition and at the Cretaceous-Tertiary boundary. The Jurassic-Cretaceous and Cenomanian-Turonian boundaries (the latter marked by the disappearance of ichthyosaurs) are potential crisis periods, but current data are not sufficient to reach conclusions. The Ladinian-Carnian transition is characterized by the disappearance of 64 % of families and affects essentially coastal forms. This extinction coincides with an important regressive phase. During the Upper Triassic, a faunal reorganisation within marine reptiles leads to the progressive disappearance of near-shore forms and to the development of pelagic groups. During the Maastrichtian-Danian crisis, 36% of families died out. Large-sized pelagic forms such as mosasaurs and elasmosaurs were the most affected and their extinction seems to have been rather sudden. On the other hand, pliosaurs and protostegid turtles became extinct, but were already declining. The survivors were near-shore forms such as crocodiles, snakes and some turtles and they may have taken refuge in freshwater environments. A break in the food chain based on phytoplankton is proposed as an extinction scenario for pelagic forms.

      


  PV article infos

Published in Vol. 24, Fasc. 3-4 (1995)

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Rates of evolution in divergent species lineages as a test of character displacement in the fossil record : tooth size in Paleocene Plesiadapis (Mammalia, Proprimates)
Phillip D. Gingerich Logo
Published online: 16/12/1996

Keywords: character displacement; character divergence; fractal time series; Plesiadapis; Rates of evolution

https://doi.org/10.18563/pv.25.2-4.193-204

  Abstract

    Two species lineages of North American late Paleocene Plesiadapis exhibit a pattern of size divergence from a common ancestral lineage. Time series of fossils in each of these lineages are analyzed to test the idea that size divergence represents competitive character displacement. The critical factor in a test of character divergence is showing that divergent lineages evolved directionally rather than randomly (multifactorially). Analysis of evolutionary rates and their temporal scaling in Plesiadapis shows that both divergent species lineages have the scaling slope expected for lineages evolving randomly rather than directionally, and size divergence in Plesíadapis does not represent character displacement. Rates of evolution commonly observed on a per-generation time scale are high enough to produce character displacement within a few generations. Thus character displacement is not likely to be visible on scales of time that can be studied in the fossil record. 


  PV article infos

Published in Vol. 25, Fasc. 2-4 (1996)

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Page 17 of 19, showing 20 record(s) out of 366 total