CHAPTER 6

Section 3

PRIMATES 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

PRIMATES 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

PRIMATES

What are the two groups of primates?

1. Strepsirhines1. Lemurs2. Tarsiers

2. Haplorhines1. Monkeys2. Apes3. Humans

STREPSIRHINES

HAPLORHINES

HOMINIDS

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

AFRICAN ORIGINS

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

EARLY HUMANS

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

HUMANS

Homo sapiens Humans today

Evolved about 400,000 years ago

By 125,000 years ago there were 2 early human groups

1. Neanderthals2. Cro-Magnon

NEANDERTHALS 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

CRO-MAGNON HUMANS

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