26 mars 530000000 av. J.-C. - Pikaia

Description:

-oldest known chordates
-v-shaped pattern in fossil records

Sources:
http://eweb.furman.edu/~wworthen/bio440/evolweb/cambrian/pikaia.htm
https://evolution.berkeley.edu/evolibrary/images/pikaia_notochord.jpg

Ajouté au bande de temps:

Date:

Les images: