i) Many origins of gregarious larvae in Heliconiini
Overall, we recorded 23 gregarious species (Figure 1A), out of the 75 Helicoiniini included in Kozak et al. (2015). Our model estimated there have been seven independent transitions to gregariousness across the Heliconiini phylogeny (under the ‘all rates different model’, model comparison: X2(1) = 4.812, p = 0.028, transition rate = 0.024)). Despite this pattern of convergent evolution, the phylogenetic signal of social behaviour is estimated to be very strong (λ = 1), likely reflecting the general tendency for transitions to occur at the base of specious clades. Transitions between solitary and gregarious states are most likely to occur at different rates, with 11 reversals from gregarious larvae back to solitary larvae across the phylogeny (transition rate = 0.078). This dynamic turnover of social behaviour suggests Heliconiini oviposition behaviour is likely responding to a range of selection pressures.