Precocious Dinosaur Sex

Part of the reason why I love science blogging is that there are usually enough people with interest in a particular field that a lot more research gets covered over the whole blogosphere than any one author could accomplish alone. While I'm still mired in some papers I downloaded last week, Darren has posted a new (and fascinating) piece on "teenage pregnancy" in dinosaurs. You'll have to see Tetrapod Zoology for the details, but be sure to stop by PNAS and get the paper "Sexual maturity in growing dinosaurs does not fit reptilian growth models," by Lee and Werning, too. If you recall, Erickson et al. published a paper ("Growth patterns in brooding dinosaurs reveals the timing of sexual maturity in non-avian dinosaurs and genesis of the avian condition," in Biology Letters) on the same topic last year that seems to support the idea that dinosaurs were reproductively mature before they attained fully adult body size, a pattern that differs from both other reptiles and from modern birds. These findings certainly will have bearing on the debate surrounding dinosaur metabolic rates and endothermy, especially since the new PNAS paper suggests that earlier sexual maturity in dinosaurs (as evidenced by medullary bone) might be a trait that goes all the way back to the saurischian/ornithischian split rather than being a trait associated only with theropods. I've probably already said too much, but it's definitely some big news and I'm looking forward to more research on this topic in a greater variety of dinosaurs.