Evolutionary History(3):
- Estimates from molecular clock data suggest that the ancestors of the animals diverged from the ancestors of the fungi about 1 billion years ago
- Other studies say that the common ancestor of living animals may have lived sometime between 675 and 875 million years ago
- The first accepted fossils of animals range from 565 to 550 million years old: these fossils are members of an early group of multicellular eukaryotes, collectively known as the Ediacaran biota
- Neoproterozoic rocks have also yielded microscopic signs of early animals
- Animal diversification appears to have accelerated dramatically from 535- 525 million years ago, during the Cambrian period of the Paleozoic era [Cambrian explosion]