The fossil’s reproductive anatomy is so advanced that researchers ... Researchers had earlier found a 44-million-year-old fossil of a pregnant horse, but the reproductive tract was not as ...

This picture, or cell atlas, highlights key similarities in immune cells between early human and horse pregnancy, a surprise given the vastly different placentas. Unlike most mammals, implantation ...

"We were able to study the impact of chromosome errors across the entire pregnancy in the horse," de Mestre said. "We found that triploidy is only associated with losses in early pregnancy." ...