Ancestor of all animals identified in Australian fossils
phys.org- First ancestor of most animals, including humans, has been discovered—Ikaria wariootia had a mouth, anus, gut, and a bilaterian body plan.
- Bilateral symmetry was a critical step in evolution, enabling organisms to move purposefully, but so far the first organism to develop it wasn’t known.
- Ikaria wariootia was discovered through careful analysis of 555 million-year-old samples.
- It was a wormlike creature, up to 7mm (0.27in) long, with a distinct head and tail, as well as faintly grooved musculature.
- This discovery confirms what evolutionary biologists previously predicted.