How to tell if a T. rex is expecting
Chemical test of fossil detects a kind of estrogen-fueled bone that’s also found in egg-producing female birds
IT’S A GIRL New chemical analyses can reveal whether a T. rex was “pregnant,” and thus female, by detecting the presence of loosely woven “medullary bone” (light colored material in inset picture) inside a fossilized bone.
Sofia Santos/Shutterstock, inset: M. Schweitzer et al/Scientific Reports 2016