In a new research collaboration between the University of Witwatersrand and the University of Adelaide, previously held views on the evolutionary development of the human brain are being challenged. The findings of their studies, published today inthe Royal Society Open Science*, unseats previous theories thatthe progression of human intelligence is simply related to the increase in size of the brain.
Their research found that while brain size has increased by about350% over human evolution, blood flow to the brain increasedby an amazing 600%.The increase in the supply of blood to the brain appears to be closely linked to the evolution of human intelligence where the human brain has evolved to become not only larger, but more energetically costlyand blood thirsty than previously believed.
Wits Brain Function Research Group co-author Dr Edward Snellingsays: "Ancient fossil skulls from Africa reveal holes where the arteriessupplying the brain passed through. The size of these holes show how blood flow increased from 3 million year old Australopithecusto modern humans."
These are Hominin skull casts used to measure the supplyof blood to the brain. Credit: Photo credit: Roger Seymour
source: University of the Witwatersrand