Category: pre-Cambrian

In “Ancient Jelly Simplifies Animal Tree?” (The Scientist , September 9, 2011 Sabrina Richards reports “A newly discovered fossil of a nearly 600-million-year-old comb jelly ancestor may call for scientists to rethink early animal evolution.” Just think: 600 million years old. Well, Like vertebrates, cnidarians exhibit bilateral or biradial symmetry—meaning they can be bisected into… more