C HAPTER 6 Section 3

P RIMATES What type of species belong to group Primates? Humans, monkeys, and apes All are mammals What characteristics do all Primates have? Opposable thumbs Binocular vision Flexible shoulders These characteristics indicate that all primates evolved from a common ancestor

P RIMATES Opposable thumbs Allow you to cross your thumb over your palm and touch your fingers This is what allows us to hold things Allow tree-dwelling primates to hold on to branches Binocular vision Permits you to judge depth or distance with your eyes Flexible shoulders Allow tree-dwelling primates to move from branch to branch Allows humans to backstroke

P RIMATES What are the two groups of primates? 1. Strepsirhines 1. Lemurs 2. Tarsiers 2. Haplorhines 1. Monkeys 2. Apes 3. Humans

S TREPSIRHINES

H APLORHINES

H OMINIDS 4 – 6 million years ago humanlike primates appeared that were different from other primates Hominids Eat meat and plants Walk upright on two legs Share some characteristics with gorillas, orangutans, and chimpanzees. They have a larger brain which separates them from apes

A FRICAN O RIGINS 1920s a skull was discovered in South Africa Had a small space for a brain Humanlike jaw and teeth Australopithecus – one of the oldest hominids discovered In 1974 an almost complete skeleton was found in Africa Thought to have walked upright This fossil indicates that modern hominids may have evolved from similar ancestors

E ARLY H UMANS 1960s a hominid fossil which was more like present-day humans was found The hominid was named Homo habilis Between 1.5 – 2 million years old Gave rise to another species known as Homo erectus 1.6 million years ago Has a larger brain Both are thought to be ancestors of humans because they have larger brains and more human like features

H UMANS Homo sapiens Humans today Evolved about 400,000 years ago By 125,000 years ago there were 2 early human groups 1. Neanderthals 2. Cro-Magnon

N EANDERTHALS Neanderthal Characteristics Short Heavy-bodies Thick Bones Small chins Heavy brow ridges Family groups lived in caves and used stone tools to hunt Disappeared from the fossil record 30,000 years ago Represent a side branch of human evolution

C RO -M AGNON H UMANS Have been found in Europe, Asia, and Australia Date from 10,000 – 40,000 years ago Stand 1.6 – 1.7 m tall Physical appearance is almost the same as modern humans Thought to be direct ancestors of early humans