The mystery of chordate origins has endured for more than 150 years. Shortly after Darwin's On the Origin of Species, acorn worms were discovered to have chordate-like pharyngeal gill slits 1,2 and to ...

The Middle Cambrian chordate known as Pikaia gracilens was once thought to be humanity’s earliest known ancestor, and the earliest known member of the phylum Chordata. Now, a new study flips this ...

Molecular studies of tunicate development show that genetic programmes for early embryonic patterning can change radically during evolution, without completely disrupting the basic chordate body plan.

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 ...