The Burden of Motherhood: Effect of Gravidity on Female Anole Behavior

Anoles only lay one egg at a time.  This penurious habit has been speculated to result from their arboreal lifestyle—because they spend so much time running around on vertical surfaces, they can’t afford to be weighed down by a big clutch of eggs.  Reasonable enough, but is there any evidence that carrying eggs has any cost to female anoles?  In a recent study in Ethology, Johnson et al. find that in A. carolinensis, as the mass of the egg increased, display behavior and movement rates decreased, suggesting that females are less active as they become more gravid.  Whether this is inactivity results because females are more vulnerable to predators or for other reasons is not known.