1. Arriving Late, Traveling Far: The Evolution of Human Beings

2. 20.1 The Human Family Tree

3. The Human Family Tree
A common primate ancestor is believed to have given rise to both the chimpanzee and the human family evolutionary lines between 6 and 7 Mya.

4. The Human Family Tree
The structure of the hominin tree is a matter of considerable debate

5. 20.2 Human Evolution in Overview

6. Human Evolution in Overview
Africa
Chad
Sahelanthropus tchadensis
Ethiopia
Earliest modern human (Homo sapiens)
Kenya
Australopithecus fossil discoveries
Orrorin tugenensis
Paranthropus fossil discoveries
Tanzania
Australopithecus and Ardipithecus fossil discoveries
South Africa
Indian Ocean
Figure 20.2

7. Human Evolution in Overview
A Hominin Family Tree
H. sapiens
Present
recent
H. neanderthalensis
H. heidelbergensis
H. floresiensis
Pleistocene
H. mauritanicus 1
H. cepranensis
H. erectus
H. habilis 2
K. rudolfensis
P. robustus
Homo ergaster
P. boisei
Au. garhi
Au. africanus
Paranthropus aethiopicus 3
Pliocene
Au. bahrelghazali
Millions of years ago
Kenyanthropus platyops
Au. afarensis 4
Australopithecus anamensis
Ar. ramidus 5
monkeys
gorillas
chimps
orangutans
hominins
Ardipithecus kadabba 6
Orrorin tugenensis
Sahelanthropus tchadensis
ancestral primate 7
Figure 20.1

8. 20.4 Snapshots from the Past: Three Hominins

9. Australopithecus afarensis
Bipedalism clearly existed in Australopithecus afarensis,
Most famous, Lucy, lived 3.18 mya in what is now Ethiopia.
Much smaller brain than modern humans
Partly arboreal, or tree-dwelling.

10. Australopithecus afarensis
Smaller brain
Longer arms (shorter legs)
Grasping feet
Figure 20.6

11. Three Hominims
Figure 20.5

12. Homo ergaster
Physical form and mental capacity much closer to ours comes with the evolution of Homo ergaster,
Turkana Boy lived 1.6 Mya.

13. Homo neanderthalensis
Neanderthals (Homo neanderthalensis) populated Europe and parts of Asia for about 130,000 years.
Went extinct 28,000 years ago in Europe.
“Caveman” image comes from the Neanderthals, though, they were more advanced and buried their dead.
Neanderthals were a primitive
species in comparison with
H. sapiens.

14. 20.5 The Appearance of Modern Human Beings

15. The Appearance of Modern Human Beings
Human beings evolved into their modern form in Africa prior to migrating into the wider world.
This is known
as the “out-of-Africa”
hypothesis

16. The Appearance of Modern Human Beings
The initial wave of human migration out of Africa was initiated sometime between 85,000 and 55,000 years ago.

17. The Appearance of Modern Human Beings
The earliest fossils we have of modern human beings outside Africa and its immediate environs date from 46,000 years ago and were found in Australia.

18. The Appearance of Modern Human Beings
Molecular evidence indicates that modern human beings evolved no earlier than 200,000 years ago.
The earliest human fossils we have date from 195,000 years ago and were found in Ethiopia.

19. The Appearance of Modern Human Beings
Arrival of Homo sapiens in Europe 40,000 years ago was followed by the extinction of Neanderthals 12,000 years later.
Arrival of human beings in Far East, 46,000 years ago, was followed by the extinction of Homo erectus 6,000 years later.

20. The Appearance of Modern Human Beings
Why are we human beings the only living species of hominin?
We “replaced” such species as H. erectus and H. neanderthalensis by out-competing
Superior weaponry and hunting; better game/food