Climatic origin shapes cold tolerance traits in European ants: a comparative study across species and populations

Details

Supervisors

Dennis, Alice ; Willot, Quentin

Faculty

Faculté des sciences

Degree label

Master [60] en sciences biologiques

Abstract

enCold environments represent a physiological challenge for ectotherm insects. Understanding how cold tolerance traits vary between species and populations of the same species is important in the context of climate change. It allows us to forecast changes in insect communities induced by new temperature conditions. In this study, three physiological traits directly or indirectly linked to cold tolerance (CTmin, LTe50 and body water content) have been measured in nine European ant species collected from the Mediterranean to the Arctic and within two populations of two of these species (C. herculeanus et F. fusca) distributed along a climatic gradient. The aim was to answer two main questions (i) do ant species show differences in their cold tolerance traits reflecting their climatic origin and (ii) do two populations of the same species show differences in cold tolerance traits and acclimation capacity. Results showed that CTmin and LTe50 are different between species, correlate with their climatic origin and correlated with climatic variables like mean and minimal soil temperature. Northern populations have also shown better cold tolerance with a lower CTmin. However, body water content did not follow the climatic gradient. In conclusion, CTmin and LTe50 are complementary traits to explain cold tolerance in ants, and this tolerance could explain the success of species in the environment they occupy.