Abstract. Birds and mammals mostly produce clutches with small numbers of large individual offspring compared to non-bird reptiles, including dinosaurs on

The Middle Permian reptile Eunotosaurus africanus is a key taxon for understanding reptile evolution because it has been proposed to be one of the earliest stem turtles, but it could alternatively ...

Abstract. Vertebrates have varied body size distributions. Among these, non-avian dinosaurs have uniquely large minimum and maximum sizes, but the reasons

Gordon et al. use a phylogenetic supervised machine-learning approach on a large original comparative dataset of limb measurements to reconstruct the evolutionary history of aquatic lifestyles in seve...

How a conserved embryonic organiser-the Sonic hedgehog (Shh)-expressing Zone of Polarising Activity (ZPA)-generates diverse limb architectures in amniotes remains a central problem in evolutionary and...

The discovery by two local fossil hunters on a river bank in Victoria has ‘potentially far-reaching implications’, scientists say Fossilised claw prints found in Australia suggest amniotes – the ancestors of reptiles, birds and mammals – evolved about 40m years earlier than thought. The footprints, in sandstone dated 354m to 358m years old, were probably made by reptiles crossing a surface dimpled by raindrops. Researchers said the trackways represent the oldest evidence of amniotes on the planet. Sign up for Guardian Australia’s breaking news email Continue reading...

In a new study published in Nature, researchers describe the extraordinary preservation of the oldest known costal breathing system in a mummified fossil from the early Permian period. The mummified f...

Amniotes exhibit a keratinized epidermis preventing water loss and skin appendages

Learn more about a mummy found in an Oklahoma cave that reveals clues about how early amniotes breathed.

Tracks in Australia seem to be the earliest known prints of amniotes — a group that includes reptiles, birds and mammals.