Data from: Correlated evolution of multiple traits gives butterflies a false head

Many butterflies possess a combination of characters at the posterior
hindwing end, superficially resembling their head. This ‘false head’ has
been hypothesised to deflect predator attacks towards the false head area.
A clear understanding of the diversity and evolution of false head traits
across butterflies is lacking. Here, we tested whether false head traits
evolved from simple to complex in order to achieve a greater resemblance
to a head. We also tested if false head traits formed an adaptive
constellation and, thus, evolved in correlation. Using a phylogenetic
framework with 927 lycaenid species, our results illustrate evolutionary
patterns of five false traits - (i) false antennae, (ii) spot, (iii)
conspicuous colouration in the false head area, (iv) false head contour in
the false head area, and (v) convergent lines. We found that false traits
(i)–(iv) evolved in a correlated fashion across the phylogeny, likely
driven by a common selective pressure. Our findings support the idea that
false head functions as an adaptive constellation for predator attack
deflection.