Figure 4: Ancestral reconstruction and the evolution of relative brain size.
From: Environmental variation and the evolution of large brains in birds
We reconstructed different character states representing different exposures to environmental variation. An example of a single reconstruction of shifts between migratory behaviours and breeding regions is shown in a, where each character state is given a distinct colour (see b for colour assignations); outside bars represent the relative brain size of each species, with representative species from the main orders shown. The median number of transitions between different character states and the 97.5 and 2.5% confidence intervals are based on 1,000 reconstructions (b). The mean and s.e. of the estimated brain optima under an OUMV model for 100 phylogenies is shown for each category (c). Silhouette illustrations came from PhyloPic (http://phylopic.org), contributed by various authors under Public domain license.
