Tropical butterflies use thermal buffering and thermal tolerance as
alternative strategies to cope with temperature increase
Abstract
Climate change poses a severe threat to many taxa, with increased mean
temperatures and frequency of extreme weather events predicted. Insects
respond to non-optimal temperatures using behaviours or local
microclimates to thermoregulate (thermal buffering ability), or through
physiological tolerance. We studied the thermal buffering ability and
thermal tolerance of a community of 54 butterfly species in Panama.
Thermal buffering ability and tolerance were influenced by family, size,
and colour, with Pieridae, large, and dark butterflies having the
strongest thermal buffering ability, and with Hesperiidae, small, and
dark butterflies tolerating the highest temperatures. We identified an
interaction between thermal buffering ability and physiological
tolerance, where species with stronger thermal buffering abilities had
lower thermal tolerance, and vice versa. This interaction implies that
most species will be vulnerable to climate change to an extent,
considering that species appear to adapt to one strategy at the expense
of the other.