Fig. 5

Heatmap showing the weighted average taxonomic composition of the gut microbial communities of Darwin’s finches grouped by season and species. Color represents the deviation from average compositional abundance of bacterial taxa, with 0% compositional abundance as white, average as light blue, below average as paler blue, and above average in dark blue (key at left). The bottom colored bar distinguishes finch samples collected during the dry (red) and wet (blue) seasons, with the sample size indicated for each finch group. Dendrograms group finches and bacterial taxa based on Euclidean distances of the compositional abundance matrix. Note the extreme deviation in the vampire finches: the average vampire finch has 15–17 times more Deferribacteres, Fusobacteria, Tenericutes, Negativicutes, and Epsilonproteobacteria than the average Galápagos finch overall