Hidden genetic diversity helped inbred brown tree snakes conquer guam

A notorious snake invasion that devastated Guam’s native birds may have succeeded because the reptiles carried hidden genetic advantages. Using advanced long-read DNA sequencing, researchers uncovered more than 19,000 large genetic differences in brown tree snakes, many concentrated in genes tied to immunity and smell. This overlooked diversity may have helped a population founded by only a few snakes survive inbreeding, adapt to a new environment, and multiply to extraordinary densities.