-
Changements environnementaux postglaciaires et action de l'homme dans le bassin du Buech et en Champsaur (Hautes Alpes, France). Premier bilan d'une étude pluridisciplinaire
-
Located in
Library
/
RBINS Staff Publications
-
Archéologie et paléoenvironnement dans les Alpes méridionales françaises - hauts massifs de l’Argentiérois, du Champsaur et de l’Ubaye (Hautes-Alpes et Alpes-de-Hautes-Provence) : Néolithique Final - début de l’Antiquité
-
Located in
Library
/
RBINS Staff Publications
-
Structures pastorales d’altitude et paléoenvironnement. Alpes méridionales françaises du Néolithique final à l’âge du Bronze
-
Located in
Library
/
RBINS Staff Publications
-
Bilan des études environnementales à Ribemont
-
Located in
Library
/
RBINS Staff Publications
-
L’environnement végétal et climatique
-
Located in
Library
/
RBINS Staff Publications
-
Vertebrate predation in the Late Devonian evidenced by bite traces and regurgitations: implications for an early tetrapod freshwater ecosystem.
-
The terrestrialization process by vertebrates occurred during the Devonian period, with fully land-dwelling tetrapods recorded in the Carboniferous. Thus, the Late Devonian is an important period for deciphering the ecological pressures that applied during the water-to-land transition. Higher predation pressures in the underwater environment have been suggested as an influential biotic evolutionary factor in this key habitat shift. Direct evidence of ancient predation on Palaeozoic vertebrates is seen in the form of rare traces preserved on fossils, and these range from trauma observed on the skeleton (such as attack marks) to ingested food remains (bromalites). The late Famennian freshwater ecosystem of Strud (Belgium) consists of a rich assemblage of many coeval gnathostomes or jawed fishes (placoderms, ‘acanthodians’, actinopterygians, and various sarcopterygian groups including tetrapods). Here we analyse the record of direct evidence for predation in the Strud vertebrate fossil assemblage. We recognize 12 regurgitalites and 13 bite traces, including a rare case of a tooth embedded in its original prey body target. Fossils from regurgitalites were imaged using scanning electron microscopy and chemically analysed to test for their possible ingestion signature by comparison with other isolated skeletal remains from the same locality. From this evidence, tristichopterid tetrapodomorphs are inferred to be the highest consumers of the trophic network, targeting small placoderms, and porolepiforms, and probably congeners. We observe two possible prey patterns in regurgitalites, for sarcopterygians and actinopterygians, both of which are associated with acanthodians. In Strud, no trophic position can be deduced for tetrapods from direct fossil evidence of predation.
Located in
Library
/
RBINS Staff Publications 2022
-
A new Placoderm fish (Acanthothoraci) from the Early Devonian Jauf Formation (Saudi Arabia)
-
An exceptionally well-preserved new acanthothoracid (placoderm fish) presenting complete endocranium and skull roof, from Saudi Arabia (Qasr Limestone Member, Jauf Formation), Early Devonian in age, is described as Arabosteus variabilis n. gen., n. sp. Compared to other Acanthothoraci, the new taxon exhibits a skull roof variable in its dermal plate distribution (e.g., a supernumerary plate: the posterior central plate) and sensory line pattern. Even the different specimens of this taxon show such variability between them. Arabosteus variabilis n. gen., n. sp. enlarges the scope of our knowledge of Acanthothoraci and Placodermi in general. Traditionally, the Arthrodira, one of the historically earliest described groups, provide the standard reference model for the placoderm skull roof pattern. The interpretation of the acanthothoracid skull roof pattern of the Saudi taxon from an arthrodiran model and the establishment of homologies is impossible to resolve unless based on prior assumptions (e.g., hypothesis of fragmentation or fusion for the paranuchal plate complex). The lateral line system of A. variabilis n. gen., n. sp. is unstable (e.g., presence or absence of the postmarginal sensory line canal) making it ambiguous to define bone homology and terminology. Consequently spatial distribution of skull roof plates has been retained for such a task with a minimal reference to the instable features of the sensory line groove distribution.
Located in
Library
/
RBINS Staff Publications
-
Inferring internal anatomy from the trilobite exoskeleton: the relationship between frontal auxiliary impressions and the digestive system
-
The digestive system of trilobites is rarely preserved. As a result, many aspects of its organization remain unknown. Fortunately, the exoskeleton sometimes preserves evidence of soft-tissue attachment sites that can be used to infer internal anatomy. Among them are the frontal auxiliary impressions (FAIs), probable soft-tissue insertion sites located on the fronto-median glabellar lobe of some trilobites. FAIs are herein described in the Carboniferous trilobite Phillipsia belgicaOsmólska 1970– representing the only known example of such structures in the Proetida and their youngest occurrence. A taphonomic scenario is proposed to explain their variable preservation. Although particularly common in the Phacopina, FAIs or FAI-like structures are also found in several orders that differ greatly. Comparisons with modern analogues suggest that FAIs might represent attachment sites for extrinsic muscles associated with a differentiated crop within the foregut. A review of purported remains of the trilobite digestive system indicates that it usually consisted of a tube-like tract flanked by a variable number of metamerically paired diverticulae. Its anterior portion is not particularly individualized, except in a few specimens that might hint at the presence of a crop. This differentiation of a crop might have constituted a secondarily evolution of the foregut in trilobites, occurring independently in different clades. Accompanied by a strengthening of associated extrinsic muscles, this modification of the foregut might explain the presence of more conspicuous muscle insertion sites on the glabella. Study of FAIs might therefore provide new data on the anatomy of the foregut in trilobites and evidence of diverse feeding habits.
Located in
Library
/
RBINS Staff Publications
-
Reducing marine eutrophication may require a paradigmatic change
-
Located in
Library
/
RBINS Staff Publications 2018
-
Modelling the marine eutrophication: a review
-
Located in
Library
/
RBINS Staff Publications 2018
