The thermal tolerance of ectotherms is a critical factor that influences their distribution, phys... more The thermal tolerance of ectotherms is a critical factor that influences their distribution, physiology, behaviour, and, ultimately, survival. Understanding the factors that shape thermal tolerance in these organisms is, therefore, of great importance for predicting their responses to forecasted climate warming. Here, we investigated the voluntary thermal maximum (VTmax) of nine grassland viper taxa and explored the factors that influence this trait. The small size of these vipers and the open landscape they inhabit render them particularly vulnerable to overheating and dehydration. We found that the VTmax of grassland vipers is influenced by environmental temperature, precipitation, short-wave flux, and individual body size, rather than by phylogenetic relatedness. Vipers living in colder environments exhibited a higher VTmax, contradicting the hypothesis that environmental temperature is positively related to VTmax. Our findings emphasize the importance of considering local to reg...
Immune genes of the major histocompatibility complex (MHC) are among the most polymorphic genes i... more Immune genes of the major histocompatibility complex (MHC) are among the most polymorphic genes in the vertebrate genome. Due to their polymorphic nature, they are often used to assess the adaptive genetic variability of natural populations. This study describes the first molecular characterization of 13 partial MHC class IIB sequences from three European ranid frogs. The utility of previously published primers was expanded by using them to successfully amplify eight exon 2 alleles from Rana arvalis.We also designed a novel primer set that successfully amplified exon 2 from Pelophylax kurtmuelleri. Pelophylax lessonae was also designed as part of this study. Results indicate the presence of one or two class IIB loci in these three species. In R. arvalis, significant evidence of positive selection acting on MHC antigen binding sites was found. Many European ranid populations are experiencing disease-related declines; the newly developed primers can, therefore, be used for further population analyses of native frogs.
The direction and magnitude of inter-sexual differences in body and head size in one eastern slow... more The direction and magnitude of inter-sexual differences in body and head size in one eastern slow-worm ( A. f. colchica ) population were investigated. We compared morphological measures of 92 male and 127 female adult A. f. colchica from a single population. In line with our expectations, we found that females were generally larger, but males had larger relative head size. At similar growth rate a disproportionate increase of head size in males and respectively of body size in females are pointed. The sexual difference in relative head size increased with the size (a proxy for age) of the animals. Our results fits well to the general theory, especially when studies of the reproductive biology of the species — reporting vigorous male-male combats, the presence of copulatory bites, and showing that female fecundity is size dependent — is taken into account. However, considering this generalist species, another common hypothesis suspecting dietary divergence between sexes behind sexua...
In recent decades, many reptile species have been introduced outside their native ranges, either ... more In recent decades, many reptile species have been introduced outside their native ranges, either accidentally through the transportation of goods and materials (e.g., plants, construction materials), but also intentionally through the pet trade. As a paradigmatic example, the Italian wall lizard, Podarcis siculus, native to the Italian Peninsula, Sicily and the north Adriatic coast, has been introduced in several nearby islands since historical times (Corsica, Sardinia, Menorca). Besides these regions, scattered populations were later reported from the Iberian Peninsula, France, Switzerland, Turkey, Greece, the United Kingdom and North America. Here, we provide molecular evidence regarding the introduction and origin of P. siculus in six new populations outside its native range: Romania (Bucharest and Alba Iulia), inland Croatia (Zagreb and Karlovac), Italy (Lampedusa Island) and Azerbaijan (Baku). Phylogenetic analysis suggests that the Alba Iulia (Romania) population originated fr...
It is generally considered that terrestrial chelonians often cope surprisingly well with carapace... more It is generally considered that terrestrial chelonians often cope surprisingly well with carapace trauma and it is common to encounter animals with chronic healed shell deformities resulting from previous traumatic episodes. Terrestrial chelonians may incur traumatic shell injuries as a result of being run over by cars or lawnmowers, burned as consequence of wrong pasture management, or gnawed by predators, or they may merely have suffered a significant fall. Here I present the description of two extreme cases of regeneration in Testudo graeca ibera in nature. In one case the tortoise survived an injury that covered more than 50 % of the carapace. The possible causes of injuries are also listed.
MHC genes are well characterized in mammalian and bird species however few data are available fro... more MHC genes are well characterized in mammalian and bird species however few data are available from reptile species, especially from snakes. Herein we report the identification of a 113 bps long sequence of the MHC class II B gene exon 2 in two Natricine species, Natrix tessellata (dice snake) and Natrix natrix (grass snake). Being too short our sequences cannot be used for population structure or phylogeographic analysis, however they can be used for the design of specific primers and they are a stepping stone for the identification of the whole MHC class II genes in these snake species.
The thermal tolerance of ectotherms is a critical factor that influences their distribution, phys... more The thermal tolerance of ectotherms is a critical factor that influences their distribution, physiology, behaviour, and, ultimately, survival. Understanding the factors that shape thermal tolerance in these organisms is, therefore, of great importance for predicting their responses to forecasted climate warming. Here, we investigated the voluntary thermal maximum (VTmax) of nine grassland viper taxa and explored the factors that influence this trait. The small size of these vipers and the open landscape they inhabit render them particularly vulnerable to overheating and dehydration. We found that the VTmax of grassland vipers is influenced by environmental temperature, precipitation, short-wave flux, and individual body size, rather than by phylogenetic relatedness. Vipers living in colder environments exhibited a higher VTmax, contradicting the hypothesis that environmental temperature is positively related to VTmax. Our findings emphasize the importance of considering local to reg...
Immune genes of the major histocompatibility complex (MHC) are among the most polymorphic genes i... more Immune genes of the major histocompatibility complex (MHC) are among the most polymorphic genes in the vertebrate genome. Due to their polymorphic nature, they are often used to assess the adaptive genetic variability of natural populations. This study describes the first molecular characterization of 13 partial MHC class IIB sequences from three European ranid frogs. The utility of previously published primers was expanded by using them to successfully amplify eight exon 2 alleles from Rana arvalis.We also designed a novel primer set that successfully amplified exon 2 from Pelophylax kurtmuelleri. Pelophylax lessonae was also designed as part of this study. Results indicate the presence of one or two class IIB loci in these three species. In R. arvalis, significant evidence of positive selection acting on MHC antigen binding sites was found. Many European ranid populations are experiencing disease-related declines; the newly developed primers can, therefore, be used for further population analyses of native frogs.
The direction and magnitude of inter-sexual differences in body and head size in one eastern slow... more The direction and magnitude of inter-sexual differences in body and head size in one eastern slow-worm ( A. f. colchica ) population were investigated. We compared morphological measures of 92 male and 127 female adult A. f. colchica from a single population. In line with our expectations, we found that females were generally larger, but males had larger relative head size. At similar growth rate a disproportionate increase of head size in males and respectively of body size in females are pointed. The sexual difference in relative head size increased with the size (a proxy for age) of the animals. Our results fits well to the general theory, especially when studies of the reproductive biology of the species — reporting vigorous male-male combats, the presence of copulatory bites, and showing that female fecundity is size dependent — is taken into account. However, considering this generalist species, another common hypothesis suspecting dietary divergence between sexes behind sexua...
In recent decades, many reptile species have been introduced outside their native ranges, either ... more In recent decades, many reptile species have been introduced outside their native ranges, either accidentally through the transportation of goods and materials (e.g., plants, construction materials), but also intentionally through the pet trade. As a paradigmatic example, the Italian wall lizard, Podarcis siculus, native to the Italian Peninsula, Sicily and the north Adriatic coast, has been introduced in several nearby islands since historical times (Corsica, Sardinia, Menorca). Besides these regions, scattered populations were later reported from the Iberian Peninsula, France, Switzerland, Turkey, Greece, the United Kingdom and North America. Here, we provide molecular evidence regarding the introduction and origin of P. siculus in six new populations outside its native range: Romania (Bucharest and Alba Iulia), inland Croatia (Zagreb and Karlovac), Italy (Lampedusa Island) and Azerbaijan (Baku). Phylogenetic analysis suggests that the Alba Iulia (Romania) population originated fr...
It is generally considered that terrestrial chelonians often cope surprisingly well with carapace... more It is generally considered that terrestrial chelonians often cope surprisingly well with carapace trauma and it is common to encounter animals with chronic healed shell deformities resulting from previous traumatic episodes. Terrestrial chelonians may incur traumatic shell injuries as a result of being run over by cars or lawnmowers, burned as consequence of wrong pasture management, or gnawed by predators, or they may merely have suffered a significant fall. Here I present the description of two extreme cases of regeneration in Testudo graeca ibera in nature. In one case the tortoise survived an injury that covered more than 50 % of the carapace. The possible causes of injuries are also listed.
MHC genes are well characterized in mammalian and bird species however few data are available fro... more MHC genes are well characterized in mammalian and bird species however few data are available from reptile species, especially from snakes. Herein we report the identification of a 113 bps long sequence of the MHC class II B gene exon 2 in two Natricine species, Natrix tessellata (dice snake) and Natrix natrix (grass snake). Being too short our sequences cannot be used for population structure or phylogeographic analysis, however they can be used for the design of specific primers and they are a stepping stone for the identification of the whole MHC class II genes in these snake species.
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Papers by Tibor Sos