Good moms make sure their kids eat well. Lizard moms only get one chance to do that; in most species, their mothering ends when they lay their eggs. So their one and only chance to be a good mom is to create high-quality eggs, and particularly ones with higher levels of antioxidants. But lizard dating isn't particularly drawn out and a female lizard needs a quick way to tell a potential mate she'd make a good mom. How does she do it?
Female striped plateau lizards (Sceloporus virgatus), which live on the rocky slopes of mountains in southeastern Arizona, do this with bright orange patches underneath the jaw. Scientists from the University of Puget Sound and elsewhere, reporting in the Journal of Animal Ecology, found that the size of those patches correlates with the concentration and amount of antioxidants in the yolk of her eggs, and the richness of color with antioxidant concentration.
"Thus, in female S. virgauts, female ornaments may advertise egg quality. In addition these data suggest that more-ornamented females may produce higher-quality offspring, in part because their eggs contain more antioxidants," said lead author Stacey Weiss, of the University of Puget Sound.
That advertising appears to work; previous research has shown that male striped plateau lizards prefer females with darker orange spots.