Recent archaeological find in Koobi Fora, Kenya suggests that our early ancestors might have dined on "seafood" to compensate for the energy and nutrition needed for the expansion of the brain. The excavated site dates 1.95 million years ago, which predates Homo erectus, reveals distinct faunal remains (some with evidence of butchery) and Oldowan artifacts. Detailed in latest PNAS edition, archaeologist David Braun and his team found an assemblage of bones from terrestrial and aquatic animals such as fishes, turtles and even crocodiles along with stone fragments (Oldowan tools) that are thought to be used to cut these animals with.
Braun posits that if these early hominins indeed ate these terrestrial and aquatic animals (fishes, turtles and crocodiles), then they would have ingested enough calories and fatty acids needed for the expansion of the brain without having to scavenge for animal remains. Braun thinks that these small-bodied hominins would have avoided the dangerous risk of confronting with larger scavengers.
Crocs and fish key to human evolution on PhysOrg.
Did Dining on Seafood Help Early Humans Grow These Big Brains? on Discover.
Fossils Suggest Menu That Made Humans Possible on Wired.
Early hominin diet included diverse terrestrial and aquatic animals 1.95 Ma in East Turkana, Kenya (Braun et al., 2010) on PNAS.