Seasonal Variation in the Thermoregulation Pattern of an Insular Agamid Lizard.

Ectotherms, including lizards, rely on behavioral thermoregulation to maintain their body temperature within an optimal range. The benign climate of islands is expected to favor the thermoregulation efficiency of reptiles throughout their activity period. In this study, we investigated the seasonal variation in thermoregulation in an insular population of the roughtail rock agama (Laudakia stellio) on Naxos Island, Greece. We measured body, operative, and preferred temperatures across three seasons (spring, summer, and autumn), and we evaluated the effectiveness of thermoregulation, using the Hertz index (E). Our results revealed that the effectiveness of thermoregulation was significantly influenced by seasonality. E was quite high in summer (0.97) and spring (0.92), and lowest in autumn (0.81). Accordingly, the quality of the thermal environment was significantly low during autumn, and maximum during summer. However, despite the environmental temperature fluctuations, lizards exhibited remarkable stability in body temperatures. They also adjusted their preferred temperatures seasonally and doubled the thermal niche breadth they occupied during summer, thus enhancing thermoregulation efficiency. Whether or not these adjustments are plastic or fixed local adaptations remains to be explored in further research across multiple years and seasons, including additional insular populations.

Gender differences in animal cognition science.

Women's representation in science is increasing steadily, with some fields closing gender parity in terms of participation and scientific output. Animal cognition appears to fall into that category. Our current analysis of gender author balance (women versus men) in 600 animal cognition papers supported parity in many aspects, but also revealed some remaining disparities. Women animal cognition scientists often held first authorship positions (58% of the studies), received similar numbers of citations, and published in equally high impact factor journals as men. Women were still under represented in last-author position, which often reflects seniority status (37% of last authors were women). There were interesting results when we considered the gender of teams (of two or more authors): all-women author teams were the minority in our dataset and received on average fewer citations than all men or mixed author teams, regardless of the quality of the journal (as measured by the journal's impact factor). Women more often focussed on mammals, whereas men more often focussed on fish, both as first authors and as same-gender teams. Men, as first author or in men-only teams, restricted their research more often to organisms of a single sex, compared to women, as first author and as members of a team. Our study suggests that there are many indices of the significant contribution of both women and men scientists in animal cognition, although some gender biases may remain.

How to behave when marooned: the behavioural component of the island syndrome remains underexplored.

Animals on islands typically depart from their mainland relatives in assorted aspects of their biology. Because they seem to occur in concert, and to some extent evolve convergently in disparate taxa, these changes are referred to as the 'island syndrome'. While morphological, physiological and life-history components of the island syndrome have received considerable attention, much less is known about how insularity affects behaviour. In this paper, we argue why changes in personality traits and cognitive abilities can be expected to form part of the island syndrome. We provide an overview of studies that have compared personality traits and cognitive abilities between island and mainland populations, or among islands. Overall, the pickings are remarkably slim. There is evidence that animals on islands tend to be bolder than on the mainland, but effects on other personality traits go either way. The evidence for effects of insularity on cognitive abilities or style is highly circumstantial and very mixed. Finally, we consider the ecological drivers that may induce such changes, and the mechanisms through which they might occur. We conclude that our knowledge of the behavioural and cognitive responses to island environments remains limited, and we encourage behavioural biologists to make more use of these 'natural laboratories for evolution'.