Anth. 105 Human Species – Lab 4 Report Sat Yu Ya Aung May 8, 2016 Introduction Human, apes, and other primate have different body mass, brain size, and life history, however, these results are depended on each other. By measuring the body mass, we can predict the size of their brain, the length of their lifespan, and their age at first reproduction. According to the data analysis, if the body mass is large, the brain size will be larger, lifespan will be longer, and the age of reproduction will be later. Compare to other apes, human have the largest body mass. Therefore, human’s encephalization quotient is larger, the lifespan is longer, and the age at first reproduction is much later. In this project, we investigated the skulls of fossil of Neanderthals, Homo erectus, Homo habilis, and Australopithecus. We measured the orbit height of the eye socket and cranium measurement, which is the height, length, and width of the skulls. The orbit height helped us calculate the body mass of the species and cranium measurement helped us calculate the observe brain size of the species. These fossil hominins helped us predict and understand better of how the evolution have shaped human-like pattern of large brains, long growth period, and long maximum lifespans for humans. Hypothesis 1.Hypothesis about life history: I expect life history variables, such as age at first reproduction, in Australopithecus, Homo habilis, Homo erectus, and Neanderthals to be much later than other primates, but earlier than human.