1. Hominid Sites Earliest fossil hominid sites are in Africa
Thought to be from about 6-7 mya to about 1.6 mya
The major groups of sites are:
Ethiopia = Middle Awash valley & Hadar (Australopithecus afarensis)
Kenya = Lake Turkana
Tanzania = Olduvai Gorge
South Africa = various sites in limestone caverns centered around Sterkfontein

2. Order Primate Lemurs, Tarsiers, Monkeys, Apes
Primate Diversity
Order Primate
Lemurs, Tarsiers, Monkeys, Apes

3. What Are Primates?
Several trends in their evolution that help define primates and are related to their arboreal, or tree-dwelling, ancestry
These include changes in the skeleton
mode of locomotion
an increase in brain size
a shift toward smaller, fewer and less specialized teeth,
and the evolution of stereoscopic vision
and a grasping hand with opposable thumb

4. New World Monkeys are found only in Central and South America
New World monkeys are characterized
by a prehensile tail, flattish face
widely separated nostrils
include the howler, spider, and squirrel monkeys

5. Old World Monkey Old World monkeys
are characterized by close-set, downward-directed nostrils
like those of apes and humans
grasping hands, and a nonprehensile tail
are distributed in the tropical regions of Africa and Asia

6. Hominoidea consist of three families: the great apes the lesser apes
family Pongidae
which includes chimpanzees, orangutans, and gorillas
the lesser apes
family Hylobatidae
which are gibbons and siamangs;
and the hominids
family Hominidae
which are humans and their extinct ancestors

7. What is a hominid? Any human-like species, including us.
Bipedal (walks on two legs).
Intelligent (large brain, uses tools).
----- Meeting Notes (10/25/12 08:55) -----

8. Bipedalism became the primary adaptation of hominids
Carrying behavior
Reduction of overall heat stress - facilitates heat loss through convection by exposing body to air currents, only humans have sweat glands that produce moisture to cool body
Most energy efficient way to travel long distances
Allows for better vision in open environments & defensive action against predators by freeing hands to throw objects

9. We are still not exactly sure when the first bipedal hominids evolved, but an amazing discovery in 1974 proved that hominids were bipedal a lot earlier than previously believed. Her name was Lucy.

10. “Lucy In The Sky With Diamonds.”
Discovered in Ethiopia in 1974 (Dr. Donald Johanson)
Dated at 3.2 million years old!
40% of her skeleton was found.
Only four feet tall.
Bipedal for certain. She walked upright.
Her scientific name is Australopithecus afarensis, a distant ancestor to us, Homo sapiens.

11. Comparison between quadrupedal and bipedal locomotion
Gorillas: the ischium bone is long and the entire pelvis is tilted toward the horizontal
Humans: the ischium bone is much shorter and the pelvis is vertical

12. Pelvis shape Allowed early hominids to stand & walk upright
Gave advantage of being able to see around them on the savannah

13. Changes in brain size & skull shape
Smaller to larger brain capacity
Spinal insertion moves from rear to base of skull

14. Opening in skull reveals upright posture
Upright posture evolved before large brains
Topic 15 – Human Evolution
Opening in skull reveals upright posture

15. Brain Size and organization
New World Monkey
Great Ape
Present Day Human

16. Position of inner toe reveals upright posture

17. The Laetoli Footprints
3.6 million years old.
Even older than Lucy.
Clearly bipedal.
Also showed that these early hominids walked together.
(Dr. Mary Leakey – discovered.)

18. Hand Shape Development of more flexible opposable thumb
Allowed advanced tool use

19. Other distinguishing features
Other features that distinguish hominids from other hominoids include
a reduced face
reduced canine teeth
omnivorous feeding
increased manual dexterity
use of sophisticated tools

20. Jaw Size Jaw has reduced in size, reflecting changes in species diet
Size of teeth have generally decreased, especially canines

22. Genus Australopithecus
~ million years - Genus Australopithecus
Several Species of this genus including
A. afarensis, A.africanus, & A. boeisi
Earliest is Australopithecus afarensis
Very much apelike with an important feature. Was able to walk upright

23. Lucy (Australopithecus afarensis)

24. Australopithicenes

25. Australopithicenes

26. Homo habilis ~ 2 - 1.5 million years - Homo habilis "handy man".
Larger than Australopithecus
Larger brain
Was first to use stone tools.

27. Lucy (Australopithecus afarensis)

28. Homo habilis

29. Homo habilis and Tools.

30. Homo erectus
~ 1.5 Million years - ~ 80,000* years . Homo erectus. (Java Man)
Larger than H. habilis
Larger brain
Smaller face
Was the first to use fire
Allowed man to "break out" of Africa into Europe & Asia

31. Lucy (Australopithecus afarensis)

32. Homo neanderthalis
~130, ,000 years. Homo neanderthalis "Neanderthal man"
Probably not a direct ancestor - but another offshoot from H. erectus
Shorter, stockier, stronger than modern man. Adapted to ice age. Wore clothing
Larger brain size than modern man.
Buried dead with flowers - first evidence of religeous/symbolic thinking.

33. Lucy (Australopithecus afarensis)

34. Cro-Magnons About 30,000 years ago,
humans closely resembling modern Europeans moved into the region inhabited by the Neanderthals and completely replaced them
Highly skilled nomadic hunters, Cro-Magnons followed the herds in their seasonal migrations
They used a variety of specialized tools in their hunts, including perhaps the bow and arrow
They sought refuge in caves and rock shelters and formed living groups of various sizes
Cro-Magnons were also cave painters

35. “Radiation” theory of H. sapien evolution

36. “Modern” man ~ 100,000 years to present - Homo sapiens (modern man).
Appears to have originated from H. erectus in Africa, then migrated outwards to Europe & Asia.
Replaced existing species H. erectus & H. neanderthalis

37. Could this mean we all might have come from Africa?
Perhaps And recently, DNA analysis has supported this idea.

38. We may all be Africans.
DNA testing of thousands of humans today, using a simple saliva test kit, has created a “map” of human migration since modern humans first left Africa 80,000 years ago.

39. We now have an excellent “road map” of how humans evolved from Africa and migrated to populate the rest of the earth. This evidence matches the fossils and fills in the gaps.

40. Models of Expansion

41. Replacement model On the one side are those who support
the "out of Africa" view
According to this camp, early modern humans evolved from a single woman in Africa, whose offspring then migrated from Africa, perhaps as recently as 100,000 years ago and populated Europe and Asia, driving the earlier hominid populations to extinction

42. The “Multiregional" View (Regional Continuity)
According to this hypothesis, early modern humans did not have an isolated origin in Africa, but rather established separate populations throughout Eurasia (H. erectus > H. neanderthalenis > H. sapiens
Occasional contact and interbreeding between these populations enabled our species to maintain its overall cohesiveness, while still preserving the regional differences in people we see today

43. Using fossils, artifacts, and now even our DNA, we are slowly getting a good picture of our own hominid evolution.

45. Apes adapted
As the climate changed, the primate populations also changed
Ape populations became reproductively isolated
from each other within the various forests,
leading to adaptive radiation
and increased diversity among the hominoids

47. Brain size

48. Position of inner toe reveals upright posture
Convergent big toe
Position of inner toe reveals upright posture
Hylobatidae Pongo Gorilla Pan Homo

49. Classification of primates
The primate order is divided into two suborders:
Prosimians, or lower primates
include the lemurs, tarsiers, and tree shrews,
Anthropoids, or higher primates,
include monkeys, apes, and humans

50. Hominids are not the same as modern apes.
Modern apes like chimpanzees, gorillas, orangutans are not bipedal.
Modern apes do not have a large brain case compared to ours.
Modern apes do not make tools.
However, chimpanzees are our closest relative - our DNA is 98% similar to theirs!

51. Spine Shape
Changed from "C" shape to "S" shape

52. The hominids (family Hominidae)
The primate family that includes present-day humans and their extinct ancestors
Have a fossil record extending back to almost 7 million years
Several features distinguish them from other hominoids
Hominids are bipedal;
that is, they have an upright posture,
which is indicated by several modifications in their skeleton