
Spitting cobras have evolved the same venom three different times
Jan. 21 (UPI) -- Evolution has yielded tremendous biodiversity, proof that there's no one right answer. But occasionally, life's challenges inspire the evolution of the same solution -- over and over and over again. According to a new survey of spitting cobras, published Thursday in the journal Science, the deadly snakes have evolved the same instantly painful venom on three different occasions. Advertisement This example of convergent evolution, scientists argue, offers proof that spitting cobras evolved their venom for defensive purposes, undermining theories that snakes exclusively develop venom for predation. All spitting cobras use a similar delivery mechanism to spray venom at distances of up to eight feet. The snakes aim their instantly-painful venom at the eyes of potentially thre...