Whether a Triceratops, a Tyrannosaurus, or a Stegosaurus, virtually every dinosaur emerged out of an externally laid egg. But eggs are fragile and don’t fossilize that well. So paleontologists still know very little about how dinosaurs laid their eggs or what the eggs looked like. A new study is now transforming our understanding of dinosaur reproduction. The research shows that the earliest dinosaur eggs may have had leathery shells, similar to today’s turtle eggs. This is a striking contrast to the hard shells we associate with modern lizards and birds. Early dinosaur eggs: Neither soft nor …