Day-flying Lepidoptera larvae have a poorer ability to thermoregulate
than adults
Abstract
Changes to ambient temperatures under climate change may detrimentally
impact small ectotherms that rely on their environment for
thermoregulation, however there is currently a limited understanding of
larval thermoregulation. In this study we investigate the
thermoregulatory capacity (buffering ability) of 14 species of
day-flying Lepidoptera, whether this is influenced by body length or
gregariousness, differs between adult and larval life stages, and what
mechanisms are used; microclimate selection or behavioural
thermoregulation. We found that Lepidoptera larvae differ in their
buffering ability between species and body lengths. Gregariousness did
not influence species buffering abilities. Larvae are worse at buffering
air temperature than adults, and rely on different thermoregulatory
mechanisms; adults rely on behavioural thermoregulation, and larvae rely
on microclimate selection. This implies that larvae are dependent on the
area around their foodplant for effective thermoregulation. These
findings have implications for the management of land and species.