Post-natal parental care in a Cretaceous diapsid from northeastern China

Abstract

Post-natal parental care seems to have evolved numer- ous times in vertebrates. Among extant amniotes, it is present in crocodilians, birds, and mammals. However, evidence of this behav- ior is extremely rare in the fossil record and is only reported for two types of dinosaurs, and a varanopid ‘pelycosaur’. Here we report new evidence for post-natal parental care in Philydrosaurus, a choris- todere, from the Yixian Formation of western Liaoning Province, China. We review the fossil record of reproduction in choristoderes, and this represents the oldest record of post-natal parental care in diapsids to our knowledge.