Séminaires DEPE

[cancelled] BEEPS: Global change : Causal climate drivers, physiological responses and consequences for population viability of ectotherms a case study: the common lizard, Lacerta vivipara

par Sandrine Meylan

Europe/Paris
Description

Climate change should lead to massive loss of biodiversity in most taxa, but the detailed physiological mechanisms underlying population extinction remain largely elusive so far.

Moreover, identifying the early warning signals of catastrophic extinctions become a central focus for ecologists. In vertebrates, baseline levels of hormones such as glucocorticoids (GCs) may be indicators of population state as their secretion to chronic stress can impair survival and reproduction. However, the relationship between GC secretion, climate change and population extinction risk remains unclear. But Telomere length (TL) represents also a promising molecular tool, since telomere attrition is associated with aging processes and accelerates after a recurrent exposure to environmental stressors.

In the southern margin of their range, populations of the common lizard (Zootoca vivipara) recently became extinct at lowest elevations due to changes in climate conditions. However, the proximal signals involved in these demographic declines are still unknown. Using two complementay approaches in natural and controlled conditions, we investigated whether climate conditions alter physiological responses and mediate reproductive trade-offs in viviparous populations of the common lizard (Zootoca vivipara).