Figure 1
From: Natural hybridization in heliconiine butterflies: the species boundary as a continuum
Phylogenetic relationships in the Heliconiina. The phylogenetic tree is based on a Bayesian/MCMC consensus tree obtained using a combination of mtDNA (CoI+CoII, 16S RNA), and nuclear genes (elongation factor-1α, apterous, decapentaplegic and wingless) [30]. * = Species known to hybridize with at least one other species in nature. The tree has been rooted using Boloria and Acraea. To give an idea of the relative time course of heliconiine evolution, HKY+gamma branch lengths have been estimated using the full likelihood rate-smoothing local molecular clock method of [101] on the CoI+CoII mitochondrial sequence data alone, after calibrating at the root with the estimated HKY+gamma average divergence between all heliconiines and Acraea (0.377).