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The variability in behavioural syndromes at different scale levels (e.g., within population or among species) is relevant in ecological and evolutionary patterns. It provides the basis on which natural selection can act to promote evolutionary processes. Additionally, behavioural syndromes can be seen as a form of pre-adaptation, favouring a species’ ability to cope with novel selective pressures, establish in new habitats, enhancing population stability, and dealing with deseases and parasites. We assessed repeatability (two replicates for individual) for five behavioural traits (activity, boldness including components of exploration and escape, sociability, and foraging activity) and tested the occurrence of behavioural syndromes in both sexes of three taxa of lacertid lizards: two clades of the common wall lizard (Podarcis muralis maculiventris and P. m. nigriventris), and the Italian wall lizard (Podarcis siculus). All behavioural traits except sociability were repeatable in all the three taxa. Our findings clearly reveal the occurrence of a behavioural syndrome related to the propensity to move through and explore new enviroments, escape from predation risk, and successfully capture prey. We also provide empirical evidence for higher repeatability of behaviours in males compared to females, as well as differences in behavioural syndromes at the taxon-level. These results support the occurrence of personality in both common and Italian wall lizards, highlighting marked variability in personality across different scales. This variability could ultimately reflect the interaction between the specific needs inherent in both sexes within each species, and the environmental/competitive context in which these needs are fulfilled. [ABSTRACT FROM AUTHOR]

A study on 81 individuals (18–75 years old) with mildly impaired fasting blood glucose (FBG) concentrations (98–125 mg/dL) was undertaken to investigate the tolerability of a food supplement (FS) based on Zea mays and Gymnema sylvestre extracts, zinc, and chromium and its efficacy on glucose and lipid metabolism. The subjects were randomized into three groups (27 in each group) and supplemented with one or two tablet(s)/day of FS (groups 1 and 2, respectively), or two tablets/day of placebo (group 3). Blood sampling was carried out at baseline (t0) and after a 3-month treatment (t1), and biochemical parameters associated with glucose and lipid metabolism and kidney and liver toxicity were evaluated. Compared to the placebo, FBG and glycated haemoglobin (HbA1c) were significantly (p < 0.001) reduced in group 1 subjects. In contrast, at the doses of one and two tablet(s)/day, the FS exerted no effect on the other parameters examined. We conclude that in subjects with slightly impaired FBG, ingestion of a FS based on Z. mays and G. sylvestre extracts, zinc, and chromium over 3 months lowers FBG and modulates glucose homeostasis by improving glucose metabolism. These beneficial effects occur in the absence of biochemical evidence of kidney and liver toxicity. [ABSTRACT FROM AUTHOR]

Copulatory organs are a key trait in reproductive compatibility and sexual isolation. The role of male genitalia in boosting mating success is well known and is often the outcome of behavioural and biological constraints, although no clear and common interpretation about their evolution appears broadly applicable. In snakes, hemipenial morphology has often been described under the perspective of sexual selection, taking into consideration both behavioural and morphological traits of both sexes. We investigated hemipenial morphology and ornamentation in the two subspecies of Hierophis viridiflavus, a male-male combating colubrid, and compared it to the sister species H. gemonensis, to assess intraspecific variation in size of genitalia and ornamentation richness. The male intromitted organ of this species is unilobed and bulbous, with rich ornamentations consisting of basal spines and apical calyculations. We detected no statistically significant difference in hemipenial size, basal spine count, and spine length between the two subspecies, suggesting that no copulatory barrier is present between the two clades. Although hemipenial morphology and anatomy do not seem suitable to assess intraspecific variability as shown in this study, they are often highly variable at the family or genus level, suggesting that the evolution of male genitalia is linked to phylogenetic relationships and that hemipenial divergence might be correlated to lineage splitting despite not being necessarily the main cause. Future studies should be aimed at investigating hemipenial morphology and anatomy across species under the perspective of comparative phylogeny and reproductive behaviours to address thoroughly the constraints of hemipenial evolution and development. [ABSTRACT FROM AUTHOR]

Speciation is the fundamental process that underlies the diversification of species. Different steps of speciation, such as reproductive isolation or ecological niche separation, can evolve in different orders and over different time scales. The two subspecies of the green whip snake, Hierophis viridiflavus viridiflavus and Hierophis viridiflavus carbonarius , sometimes considered as separate species, are ideal to study speciation because they diverged in isolated glacial refugia. So far, little is known about whether these two subspecies are reproductively isolated from each other. Furthermore, it is unknown whether the common melanism of the subspecies H. v. carbonarius might be genetically encoded. We quantified gene flow along two transects across the contact zone of the two subspecies using double-digest restriction site-associated DNA. Our analyses implicated the existence of two well-defined clades that experience substantial gene flow along a contact zone that is ~300 km wide. We detected a clear association between the genetic assignment and the quantitative extent of melanism within the contact zone, which is likely to be genetically polygenic. Given the level of gene flow, it seems that strong postzygotic reproductive barriers have not evolved. We conclude that the two subspecies represent evolutionarily significant units for conservation and suggest treating them taxonomically as subspecies. [ABSTRACT FROM AUTHOR]