A Y By D. Charles Deeming
Ninety years have passed since Roy Chapman Andrews returned from his exploration of Mongolia with tales of fossilized dinosaur eggs (1). Fossils interpreted as dinosaur eggs had been described before, but Chap-
That these flying reptiles even laid eggs
man’s crew had found fossils that could only
be interpreted as clutches of eggs. Recent
fossil evidence of dinosaur reproduction
has confirmed that all dinosaurs laid eggs,
whereas other Mesozoic groups, such as the
aquatic ichthyosaurs, evolved live birth (2).
However, the reproductive biology of a key
group of extinct Mesozoic species, the flying
pterosaurs (see the image), has remained
elusive. On page 1197 of this issue, Wang et
al. (3) report the largest accumulation of
Hamipterus pterosaur eggs found to date.
The work is a crucial advance in under-
standing pterosaur reproduction.
was only recently confirmed in 2004, with
Hundreds of fossil eggs elucidate embryo development and nesting behaviors of pterosaurs
How pterosaurs bred
sciencemag.org SCIENCE 1124 1 DECEMBER 2017 • VOL 358 ISSUE 6367