Nothing in Biology Makes Sense: Incubation temperature tailors these skinks to their habitat

Closed-litter Rainbow-skink (Carlia longipes) Carlia longipes. Photo by berniedup.

This week at Nothing in Biology Makes Sense, there’s a post from yours truly about a curious case of developmental flexibility in some Australian lizards. It seems that rainbow skinks (Carlia longipes) develop bigger bodies and longer legs if they’re incubated in cooler nests—and those developmental changes provide an advantage in the rocky habitats where nest temperatures are typically cooler:

Life is risky for a newly hatched lizard. You have to make your way in a habitat you’ve never seen before, full of all sorts of larger animals that think you’d make a decent snack, if maybe not a full meal. Wouldn’t it be nice if you could’ve been preparing for the conditions you’ll meet out there even before you crack through that shell?

Well, for one species of skinks, it looks like this may be exactly what happens. A recent paper in The American Naturalist makes the case that rainbow skinks (Carlia longipes) develop in their eggs to match the habitat conditions around their nest—based on the temperature of the nest.

This is a classic case of phenotypic plasticity, in which development responds to the environment to provide a better fit—but in Carlia longipes, plasticity goes beyond growing longer legs. To find out what’s up with these skinks, go read the whole thing.◼