I'm of the belief that humans are a pescatarian hominid
Far too much protien needed for big, energy hungry, nervous systems to function on a vegan diet.
Not quite specialized enough to be obligate carnivores (claws, protruding maw, enlarged canines).
Best case for a functional opposable thumb is fish, crustacean, and mollusk predation.
First Spears and knives for catching fish, dehusking yummy lobsters and opening oysters and clams.
circulatory systems seem to fail on anything not containing massive amounts of Omega-3.
Besides I think their yummy
Aquaponics also kick serious ass growing cannabis.