Question

What do you expect encephalization quotient in Australopithecus, Homo habilis, Homo erectus, and Neanderthals to look like compared to humans? What about compared to other primates?

Answer 1

Encephalisation quotient predicts the intelligence of different species. EQ = Ea/Ee and it describes how much the actual brain size (Ea) varies from expected brain size(Ee) . It is not the raw brain to body mass ratio but is the relative brain size and it is the ratio between observed to predicted brain mass for an animal of a given size and considers allometric effects. In simple words it describes how small or large, a species brain is when compared to other species of same body size. Encephalisation quotient mainly consider the size of brain cortex compared to other parts of the brain, because as the brain size increases the brain cortex is increasing. Enencephalisation quotient is something different from the actual brain size and it defines the intelligence. Humans are having the highest encephalisation quotient which is EQ 7.4–7.8  .So definitely when Australopithecus, Homo habilis, Homo erectus, and Neanderthals are compared to humans , humans are having the highest encephalisation quotient . Australopithecus, Homo habilis, Homo erectus, and Neanderthals are human primates and are intellectualy stronger and will be having high EQ when compared to non human primates.