Male eastern fence lizardLANGKILDE LAB, PENN STATE UNIVERSITYSpring is a busy time for the eastern fence lizards, Sceloporus undulatus. Across the eastern U.S., sexually mature males—with bright blue badges on the sides of their white bellies—court females. Eager to mate, territorial males flaunt their blue badges to win females and ward off intruding males.
Yet many females also don blue ornamentations like the males, though they are less bright. These so-called “bearded ladies”—masculinized females—suffer reproductive consequences as a result of their markings. According to a study published in Biology Letters today (November 6), females with blue badges appear less attractive to males and reproduce later in the mating season than their unmarked counterparts.
Intrigued that females vary in ornamentation, Pennsylvania State University’s Lindsey Swierk and Tracy Langkilde sought to evaluate the effects of such traits on females. They collected female S. undulatus lizards from the field and monitored their reproduction in the lab. Then, using lizards reared in the lab, the researchers presented individual males with two tethered females—one with blue badges and one without—tracking the males’ courtship behaviors.
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