Penn State biologist Tracy Langkilde has shown that native fence lizards in the southeastern United States are adapting to potentially fatal invasive fire-ant attacks by developing behaviors that enable them to escape from the ants, as well as by developing longer hind legs, which can increase the effectiveness of this behavior. Not only does this finding provide biologists with an example of evolution in action, but it also provides wildlife managers with knowledge that they can use to develop plans for managing invasive species. Langkilde conducted an experiment in which she compared the responses to fire ant attacks of lizards that were collected from four different sites: one that had not yet been invaded by fire ants and ones that were invaded by fire ants 23, 54, and 68 years ago. Her goal was to determine whether the amount of time since invasion influences the ways in which lizards respond to attacks. She found that the lizards from sites that have been invaded the longest were more likely than the lizards from sites that have not yet been invaded to twitch vigorously to remove ants and then to run away from the mound. She also found that the lizards with the longest hind legs were the most successful at getting away from ants.
No comments:
Post a Comment