I've always been a fan of convergent evolution. This example isn't quite as cool as tarsiers on Madagascar converging with owls (who aren't found on Madagascar) as there is a clear and recent shared ancestor who obviously was ready to become a spitter, but it's cool nevertheless.

From sciencemag.org:

While snakes use venom primarily for predation, and venom composition often reflects diet specificity, three lineages of cobras have independently evolved the ability to spit venom at adversaries. Using gene, protein, and functional analyses, we show that the three spitting lineages possess venoms characterized by an up-regulation of phospholipase A₂ (PLA₂) toxins, which potentiate the action of preexisting venom cytotoxins to activate mammalian sensory neurons and cause enhanced pain. These repeated independent changes provide a fascinating example of convergent evolution across multiple phenotypic levels driven by selection for defense. [emph mine -mfn]

Labels: evolution, Other Stuff