The earliest reptiles, birds and mammals may have borne live young, researchers from Nanjing University and University of Bristol have revealed. Until now, the hard-shelled egg was thought to be the ...

Despite evidence that the earliest examples of creatures such as mammals and reptiles gave birth to live young, they actually may have laid eggs, a scientist argues. Subscribe to read this story ...

The discovery of 280-million-year-old reptile embryos in Brazil and Uruguay has provided paleontologists with the oldest known fossil evidence of amniote embryos. The remains, linked to the aquatic ...

The appearance of the amniotic egg marks a key event in the evolutionary history of vertebrates. Its major adaptive advantage is the amnion — an enclosing membrane that prevents the embryo from drying ...