Search results for "Reptiles"
showing 10 items of 37 documents
Early Pliocene continental vertebrate fauna at Puerto de la Cadena (SE Spain) and its bearing on the marine-continental correlation of the Late Neoge…
2017
In this paper, we synthesize sedimentological, magnetostratigraphic and paleontological data from the continental vertebrate site of Puerto de la Cadena (Murcia, SE Spain), in order to clarify its age. The study site is located on the northern edge of the Carrascoy mountain range, in the upper part of the Cigarrón Unit. The end-Messinian discontinuity has been detected at the base of this unit, which indicates it has an early Pliocene age. Abundant remains of small and large vertebrates, including rodents, lagomorphs, primates, carnivorans, perissodactyls, artiodactyls, proboscideans, testudines, squamats, and crocodiles, have been found in this area. Some of these elements are of African o…
Dental microwear texture reflects dietary tendencies in extant Lepidosauria despite their limited use of oral food processing
2019
Lepidosauria show a large diversity in dietary adaptations, both among extant and extinct tetrapods. Unlike mammals, Lepidosauria do not engage in sophisticated mastication of their food and most species have continuous tooth replacement, further reducing the wear of individual teeth. However, dietary tendency estimation of extinct lepidosaurs usually rely on tooth shape and body size, which allows only for broad distinction between faunivores and herbivores. Microscopic wear features on teeth have long been successfully applied to reconstruct the diet of mammals and allow for subtle discrimination of feeding strategies and food abrasiveness. Here, we present, to our knowledge, the first de…
Response to formal comment on Myhrvold (2016) submitted by Griebeler and Werner (2017)
2018
In his 2016 paper, Myhrvold criticized ours from 2014 on maximum growth rates (Gmax, maximum gain in body mass observed within a time unit throughout an individual’s ontogeny) and thermoregulation strategies (ectothermy, endothermy) of 17 dinosaurs. In our paper, we showed that Gmax values of similar-sized extant ectothermic and endothermic vertebrates overlap. This strongly questions a correct assignment of a thermoregulation strategy to a dinosaur only based on its Gmax and (adult) body mass (M). Contrary, Gmax separated similar-sized extant reptiles and birds (Sauropsida) and Gmax values of our studied dinosaurs were similar to those seen in extant similar-sized (if necessary scaled-up) …
Dinosaur Metabolism and the Allometry of Maximum Growth Rate
2016
In his 2016 paper, Myhrvold criticized ours from 2014 on maximum growth rates (Gmax, maximum gain in body mass observed within a time unit throughout an individual’s ontogeny) and thermoregulation strategies (ectothermy, endothermy) of 17 dinosaurs. In our paper, we showed that Gmax values of similar-sized extant ectothermic and endothermic vertebrates overlap. This strongly questions a correct assignment of a thermoregulation strategy to a dinosaur only based on its Gmax and (adult) body mass (M). Contrary, Gmax separated similar-sized extant reptiles and birds (Sauropsida) and Gmax values of our studied dinosaurs were similar to those seen in extant similar-sized (if necessary scaled-up) …
Thermal variability during ectotherm egg incubation: A synthesis and framework.
2020
Natural populations of ectothermic oviparous vertebrates typically experience thermal variability in their incubation environment. Yet an overwhelming number of laboratory studies incubate animals under constant thermal conditions that cannot capture natural thermal variability. Here, we systematically searched for studies that incubated eggs of ectothermic vertebrates, including both fishes and herpetofauna, under thermally variable regimes. We ultimately developed a compendium of 66 studies that used thermally variable conditions for egg incubation. In this review, we qualitatively discuss key findings from literature in the compendium, including the phenotypic effects resulting from diff…
To Swim or Not to Swim: Potential Transmission of Balaenophilus manatorum (Copepoda: Harpacticoida) in Marine Turtles
2017
Species of Balaenophilus are the only harpacticoid copepods that exhibit a widespread, obligate association with vertebrates, i.e., B. unisetus with whales and B. manatorum with marine turtles and manatees. In the western Mediterranean, juveniles of the loggerhead sea turtle, Caretta caretta are the only available hosts for B. manatorum, which has been found occurring at high prevalence (>80%) on them. A key question is how these epibionts are transmitted from host to host. We investigated this issue based on experiments with live specimens of B. manatorum that were cultured with turtle skin. Specimens were obtained from head-started hatchlings of C. caretta from the western Mediterranean. …
Length of activity season drives geographic variation in body size of a widely distributed lizard
2013
Understanding the factors that drive geographic variation in life history is an important challenge in evolutionary ecology. Here, we analyze what predicts geographic variation in life-history traits of the common lizard, Zootoca vivipara, which has the globally largest distribution range of all terrestrial reptile species. Variation in body size was predicted by differences in the length of activity season, while we found no effects of environmental temperature per se. Females experiencing relatively short activity season mature at a larger size and remain larger on average than females in populations with relatively long activity seasons. Interpopulation variation in fecundity was largely…
Trade and stowaways: molecular evidence for human-mediated translocation of eastern skinks into the western Mediterranean
2020
Human movements in the regions surrounding the Mediterranean Sea have caused a great impact in the composition of terrestrial fauna due to the introductions of several allochthonous species, intentionally or not. Reptiles are one of the groups where this anthropic impact is most evident, owing to the extensive intra-Mediterranean dispersals of recent chronologies. Chalcides ocellatus is a widespread skink with a natural distribution that covers almost the entire Mediterranean Basin. Two hypotheses have been proposed to explain its origin: natural dispersions and human translocations. Previous molecular data suggest the occurrence of a recent dispersal phenomenon across the Mediterranean Sea…
Going underground: short- and long-term movements may reveal the fossorial spatial ecology of an amphisbaenian
2021
[Background]: The movement and spatial ecology of an animal depends on its morphological and functional adaptations to its environment. In fossorial animals, adaptations to the underground life help to face peculiar ecological challenges, very different from those of epigeal species, but may constrain their movement ability.
Monitoring the reproductive activity in captive bred female ball pythons (P. regius) by ultrasound evaluation and noninvasive analysis of faecal repr…
2018
The royal python (Python regius) is commonly bred in captivity. To have a successful breeding season, accurate monitoring of the reproductive activity is necessary. The use of non-invasive monitoring methods in exotics is important in order to minimize stress. For this purpose ultrasound has been anecdotally used to monitor royal python reproductive activity. However, there is limited information regarding the reproductive cycle of this species. The aim of the present study is to monitor the female reproductive cycle of the royal python using ultrasonography and gonadal steroid metabolite measurements in the faeces. The reproductive activity of one hundred twenty-nine adult female P. regius…