A new examination of ancient and current species of reptiles conducted by a University of Texas at Austin paleobiologist reveals the serious impact of the disappearance of even a few species of reptiles in some island areas. The study, published in the Proceedings of the National Academy of Sciences, has startling conclusions about how, on smaller islands in the Caribbean where human impact was greatest, extinctions have led to the loss of up to two-thirds of the supports for the ecosystem that native reptile species once provided there.

 

Although similar studies have looked at the role of large mammals or other types of animals in ecosystems over time, this is the first to do so with reptiles -- a key component of many island ecosystems.

 

Exploring what's known as functional diversity, the study goes beyond cataloging different living things in a place over time, in this case, 418 Caribbean reptile species. Instead, the study maps out the functions that those species offer that support a thriving natural environment. The 418 species can be collapsed into 123 functional entities: groupings of species that share the same suite of traits and may perform similar ecosystem services.

 

"Functional diversity is a really important measure of the health of an ecosystem," said Melissa Kemp, an assistant professor of integrative biology at UT Austin. "It's important to understand the number of species in a given system, but it's equally, if not more, important to understand the roles those species play. That's the measure of functional diversity."