Smarter lizards in the city?

We performed a detour task in the field to two syntopic lizard species, to test for cognitive differences between urban and semi-natural population

Evaluation of micronucleus and erythrocytic nuclear abnormalities in Balkan whip snake Hierophis gemonensis. Ecotoxicology 19

Abstract Over recent years, changes of erythrocytic nuclei have been increasingly used to evaluate genotoxic effects of different compounds such as polycyclic aromatic hydrocarbons (benzo-a-pyrene, naphthalene, b-naphthoflavone), heavy metals (cadmium, mercury), textile mill effluent especially in aquatic ecosystem. However, in fish, both micronuclei and erythrocytic nuclear abnormalities also appear spontaneously and their frequency can be seasonally dependent. The aim of the study was to evaluate the frequency of micronuclei (MN), nuclear abnormalities (NA) including vacuolated nuclei (VN) and cytoplasmic vacuoles (CV) in erythrocytes of Balkan whip snake Hierophis gemonensis and establish the level of spontaneous appearance during the annual cycle. Average frequency of NA was 10.89 ± 4.72% while the MN (0.03 ± 0.03%) and VN (0.04 ± 0.08%) were seldom detected. NA significantly positively correlated with MN (r = 0.319; P \ 0.05) and VN (r = 0.363; P \ 0.05). Appearance of CV did not correlate with other measured parameters and average frequency was 11.06 ± 8.33%. Significant seasonal variation was found in NA appearance with the lowest value in spring and the highest in winter. VN increase was observed in autumn. MN and CV levels varied between seasons but not significantly. Considering the biological cycle, frequency of NA, VN, MN and CV recorded in pre-hibernation/ hibernation increased compared to the active phase, but only NA elevation was significant. Although the obtained results showed differences according to sex, statistical analysis of measured parameters showed the same pattern of seasonal variation in both sexes

Plastic and genomic change of a newly established lizard population following a founder event

Abstract: Understanding how phenotypic divergence arises among natural populations remains one of the major goals in evolutionary biology. As part of competitive exclusion experiment conducted in 1971, 10 individuals of Italian wall lizard (Podarcis siculus (Rafinesque-Schmaltz, 1810)) were transplanted from Pod Kopiste Island to the nearby island of Pod Mr & ccaron;aru (Adriatic Sea). Merely 35 years after the introduction, the newly established population on Pod Mr & ccaron;aru Island had shifted their diet from predominantly insectivorous towards omnivorous and changed significantly in a range of morphological, behavioural, physiological and ecological characteristics. Here, we combine genomic and quantitative genetic approaches to determine the relative roles of genetic adaptation and phenotypic plasticity in driving this rapid phenotypic shift. Our results show genome-wide genetic differentiation between ancestral and transplanted population, with weak genetic erosion on Pod Mr & ccaron;aru Island. Adaptive processes following the founder event are indicated by highly differentiated genomic loci associating with ecologically relevant phenotypic traits, and/or having a putatively adaptive role across multiple lizard populations. Diverged traits related to head size and shape or bite force showed moderate heritability in a crossing experiment, but between-population differences in these traits did not persist in a common garden environment. Our results confirm the existence of sufficient additive genetic variance for traits to evolve under selection while also demonstrating that phenotypic plasticity and/or genotype by environment interactions are the main drivers of population differentiation at this early evolutionary stage

Data from: Form function relationships support fast ecological shift in a lizard

Macroevolutionary changes such as variation in habitat use or diet are often associated with convergent, adaptive changes in morphology. However, it is still unclear how small-scale morphological variation at the population level can drive shifts in ecology as observed at a macroevolutionary scale. Here, we address this question by investigating how variation in cranial form and feeding mechanics relate to rapid changes in diet in an insular lizard (Podarcis siculus) after experimental introduction into a new environment. We first quantified differences in the skull and jaw muscle architecture between the source and introduced population using 3D geometric morphometrics and dissections. Next, we tested the impact of the observed variation in morphology on the mechanical performance of the masticatory system using computer-based biomechanical simulation techniques. Our results show that the small differences in shape, combined with variation in muscle architecture, can result in significant differences in performance allowing access to novel trophic resources. The confrontation of these data with the already described macroevolutionary relationships between cranial form and function in these insular lizards provides insights into how selection can, over relatively short time scales, drive major changes in ecology through its impact on mechanical performance

Evaluation of micronucleus and erythrocytic nuclear abnormalities in Balkan whip snake Hierophis gemonensis

The aim of the study was to evaluate the frequency of micronuclei (MN), nuclear abnormalities (NA) including vacuolated nuclei (VN) and cytoplasmic vacuoles (CV) in erythrocytes of Balkan whip snake Hierophis gemonensis and establish the level of spontaneous appearance during the annual cycle. Average frequency of NA was 10.89 ± 4.72 % while the MN (0.03 ± 0.03 %) and VN(0.04 ± 0.08 %) were seldom detected. NA significantly positively correlated with MN (r = 0.319 ; P < 0.05) and VN (r = 0.363 ; P < 0.05). Appearance of CV did not correlate with other measured parameters and average frequency was 11.06 ± 8.33 %. Significant seasonal variation was found in NA appearance with the lowest value in spring and the highest in winter. VN increase was observed in autumn. MN and CV levels varied between seasons but not significantly. Considering the biological cycle, frequency of NA, VN, MN and CV recorded in pre-hibernation/hibernation increased compared to the active phase, but only NA elevation was significant. Although the obtained results showed differences according to sex, statistical analysis of measured parameters showed the same pattern of seasonal variation in both sexes