Between 280 and 200 million years ago, a group of animals evolved which would eventually give rise to mammals, including humans: the therapsids. They were first described more than 150 years ago, ...

Scientists discover the first fossil egg of a mammal ancestor, offering new clues to how Lystrosaurus survived extreme ...

Some of the most ancient fossils collected to date were traced back to the Ediacaran period. This is the time interval ranging from around 635 to 541 million years ago, shortly before the time when ...

Embryo development starts when a single egg cell is fertilized and starts dividing continuously. Initially a chaotic cluster, it gradually evolves into a highly organized structure. Scientists have ...

Chromosphaera perkinsii is a single-celled species discovered in 2017 in marine sediments around Hawaii. The first signs of its presence on Earth have been dated at over a billion years, well before ...

A single-celled creature originally found in shallow sea sediments around Hawaii develops into multicellular structures with remarkable similarities to animal embryos. The finding could help ...

CRCHUM researcher Sophie Petropoulos and her team reveal for the first time that the guinea pig pre-implantation embryo is very similar to the human embryo, spurring a better understanding of ...

The first few days of a human embryo’s development, known as pre-implantation, are important. It’s when the first cells are formed, and these decide if the embryo can survive, how it will implant in ...