Deadly Newt Arms Race: A Toxic Evolutionary Battle
The Rough-Skinned Newt (Taricha granulosa) of the Pacific Northwest is the world's most toxic newt, with enough poison to kill several adults. This extreme toxicity is the result of an evolutionary arms race with the common garter snake (Thamnophis sirtalis). Newts evolve greater toxicity to deter predation, while snakes evolve resistance. However, this comes at a cost: higher metabolic load for the newts and potential neurological consequences for the snakes. Intriguingly, snakes sequester the newt's toxin for their own defense against predators, maintaining a dangerous symbiosis. This complex interaction highlights the trade-offs and uncertainties of evolution, prompting further questions about interspecies relationships and ecosystem dynamics.