Cannibal Tadpoles Could Reveal Gut Secrets

by LiveScience Staff 

Date: 09 May 2013 Time: 05:12 PM ET 

They may look fairly innocuous, perhaps just a little bloated, but Budgett's frogs are aggressive creatures with cannibalistic tendencies from the time they're just tadpoles. 

Tadpoles are frogs in their young larval stages, and in most species, they're stuck with simple diets because their digestive tracts cannot process insects or proteins until they mature. 

Budgett's frogs, meanwhile, have short complex guts that can break down protein from a remarkably early age. They swallow other animals whole, sometimes even eating their own siblings. 

Researchers at North Carolina State University recently studied how this meat-eating ability evolved. The team looked at the algae-eating tadpoles of African clawed frogs (Xenopus laevis), which, 110 million years ago, had a common ancestor with Budgett's frogs. 

By exposing embryos of African clawed frogs to certain gene-deactivating molecules, the researchers created tadpoles with guts that looked more like those of Budgett's frogs, fit to digest protein. Turning the technique on the embryos of a South American species of Budgett's frogs, Lepidobatrachus laevis, the researchers said they created tadpoles with stomachs more suited for a vegetarian diet. 

Continued: http://www.livescience.com/29490-cannibal-tadpoles-budgetts-frogs.html