Science Daily reports on a new study in which a species of lizards, transplanted to a new island, evolved a number of new traits in just 36 years. As is often the case with Science Daily, I’m a little skeptical of the reporting. If the transplanted lizards experienced morphological changes, how could they be genetically “identical” to the source population? And no matter how rare these “cecal valve” structures are in lizards, the fact that they are known in other lizards should at least suggest the alternative hypothesis that they are an environmental reaction rather than a genetic change (though it could also be a very simple and common mutation that only takes hold in certain environments).
In any case, rapid evolutionary change in response to a new environment is actually nothing new. Many previous studies have transplanted species into a new environment, and then observed morphological changes (the unit of measure here is charmingly called a “Darwin“) happening that are orders of magnitude faster than the fastest changes observed in the fossil record.
Findings like these are part of why the incredulity of most creationists about the power of evolutionary change is hard to square with the known realities of biology. If anything, one of the big mysteries in evolution is not how large changes can possibly happen quickly (or happen at all), but rather just the opposite: why change seems to have happened so slowly in the past compared to the potential for speedy change that we observe in the present.