biological anthropologists have observed several chimpanzees in western africa making tools to help them hunt. the chimpanzees were seen modifying branches and sticks into spears. they removed any leaves or small branches to make a smooth shaft. they also chewed on the end of the branches to give them sharp points. they then thrust the sharpened branches like spears into tree trunks, where small primates called galagos make sleeping nests. although it remains unclear how successful the chimpanzees are in actually killing galagos, multiple members of the chimpanzee group have been observed producing the spears.how does this research relate to human evolution? in other words, what can we learn about human evolution from research along these lines?