All Life on Earth Traces Back to One Ancestor — and It’s Older Than Expected

Every human, animal, plant, fungus, and microbe alive today carries a link to the same ancient beginning. Scientists call that ancestor LUCA, the Last Universal Common Ancestor.

It was not the first life on Earth, but it is the point where the family tree of all known life can be traced back. New research suggests LUCA lived around 4.2 billion years ago, only a few hundred million years after Earth formed.

That makes it older than many scientists once expected, and it means life may have become established on our planet surprisingly quickly.