Ecological and biogeographic processes drive the proteome evolution of snake venom

The emergence of venom is an evolutionary innovation that favored the diversification and survival of snakes. The composition of snake venoms is known in detail from venom gland proteomic data. However, there is still a gap of knowledge about the forces that lead to the expression of different toxins in different proportions in the venom cocktail across space and time.

LOCATION

World.

TIME PERIOD

Modern.

MAJOR TAXA STUDIED

Elapidae and Viperidae.

We integrated proteomic data with phylogenetic comparative methods to understand how ecological and biogeographical processes drive the evolution of snake venom. We observed that more productive environments favor a more complex venom, which presents a higher diversity and similarity on the toxin proportions in its composition. We found that the taxa that live in islands, where there is lower variability of resources, tended to present  less complex venom dominated by few toxins. In this case, the island's isolation seems to be a relevant element for a faster fixation of specific venom compositions. We show that ecological and biogeographic processes, which can act differentially over time and space, affect the gene expression of toxins in snake venoms.