Italian wall lizards introduced to a tiny island off the coast of Croatia are evolving in ways that would normally take millions of years to play out, new research shows.

In just a few decades the 5-inch-long (13-centimeter-long) lizards have developed a completely new gut structure, larger heads, and a harder bite, researchers say.

This seems to support the theory that environmental pressure can produce evolutionary adaptation in large organisms over short periods of time. However, this new species could be the result of interbreeding between the two original species, producing a third species that outlasted the prior two...

Lizards Rapidly Evolve After Introduction to Island