Surprisingly, genome comparisons have failed to resolve a major question in animal evolution: Which living animals are the descendants of the earliest animals to evolve in the world's oceans?

A study published by MBARI researchers and their collaborators today in Nature provides new insights about one of the earliest points in animal evolution that happened more than 700 million years ago.

Deep, deep in geologic time, some 600 million or 700 million years ago, the very first animals evolved on Earth. Their closest relatives that still live today include sponges, sea anemones and comb ...

For more than a century, biologists have wondered what the earliest animals were like when they first arose in the ancient oceans over half a billion years ago. Searching among today's most ...