Adaptive evolution of flight in Morpho butterflies

The diversity of flying animals suggests that countless combinations of
flight morphologies and behaviors have evolved with specific lifestyles,
thereby exploiting diverse aerodynamic mechanisms. How morphology, flight
behavior and aerodynamic properties together diversify with contrasting
ecology remains to be elucidated. We studied the adaptive co-divergence in
wing shape, flight behavior and aerodynamic efficiency among Morpho
butterflies living in different forest strata, by combining high-speed
videography in the field with morphometric analyses and aerodynamic
modelling. By comparing canopy and understory species, we show that
adaptation to an open canopy environment resulted in increased glide
efficiency. Moreover, this enhanced glide efficiency was achieved by
different canopy species through distinct combinations of flight behavior,
wing shape and aerodynamic mechanisms, highlighting the multiple pathways
of adaptive evolution.