Scientists try to piece together the early history of life by backtracking to the 'last universal common ancestor.' By combining genetic data and fossils, they uncover new details about the microbe that's the source of all life on Earth.
The shape of a bird's wings depends greatly on its lineage rather than on distinctive flght styles.
Mineral clues hidden within ancient molten rocks suggest life on the planet arose 300 million years ahead of previous estimates. This changes the way scientists view the Earth following its formation 4.5 billion years ago.