Life began on Earth more than 3.5 billion years ago, but the history of humans and other vertebrates accounts for only a fraction of this timescale. Chordates (a group that includes vertebrates) and echinoderms (like starfish and sea urchins) are believed to have evolved from a common deuterostome ancestor around 500 million years ago. However, how the complex and sophisticated body plan of chordates evolved is still not fully clear, despite its importance from an evolutionary and developmental biology perspective. This topic has thus been the subject of much debate among experts for a long time.
Click here for original story, New insights into chordate body plan development answer long-standing questions on evolution
Source: Phys.org