1. Basic Trends in Hominid Evolution
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2. Homo sapiens are of the order Primates
What is a primate?
Round heads with flattened faces.
Brains that are relatively large when compared to body size.
Primate brains are also much more complex than any other land mammals.
Diverse behaviors and social interactions reflect the complexity of their brains. (language and tool making)

3. Primates also…
Opposable thumbs – the primates opposable thumbs enable it to grasp and manipulate objects.
Vision – vision is the dominant sense for primates, which is binocular.
Brain volume – a primate has a large brain relative to it’s body.
Arm movement – shoulders are unique on primates which enable wide range of arm movements.
Flexible joints – primate elbow and wrists joints make the arms unique.
Feet – a primate’s feet can grasp objects, but the degree of effectiveness of a primate’s feet can vary.

4. Hominids 5-8 million years ago in Africa a population
that spawned chimps and humans diverged
into two lines.
• One line gave way to chimps, and the other
line into modern day humans.
• The two lines are collectively called
hominids.
• Hominids are primates that can walk upright
on two legs and include gorillas, chimps,
bonobos, and humans.

5. Australopithecus

6. Australopithecine Both apelike and humanlike.
• Lucy, was discovered by paleoantrhopologist Donald Johansson, that dates back to 3.2 million years ago.
• Lucy’s skeleton was from a new species called australopithecine afarensis.
• The unique thing about Lucy was the size of her brain case. Lucy had an incredibly large brain.
• Anthropologist theorize that Australopithecine is the ancestry of modern humans.

7. Big Brains = Tools
1964 Louis and Mary Leakey described a skull that matched more closely with modern human skulls.
• The larger brain case and smaller jaw and teeth indicated human lineage.
• The Leakey’s named the species Homo habilis, which means handy human.
• This name was dubbed because of the usage of tools.
• Radiometric dating estimates life about 1.5 –2.5 million years ago.

8. Human Evolution

9. Homo erectus
Homo erectus and like fossils are found in Africa, Asia, and Europe and are dated between 1.9 and 0.3 mya.
Larger brain and flatter face than Homo habilis.
Much taller than previous hominids.
Believed to have first appeared in Africa and then migrated into Asia and Europe.
First hominid to use fire.

10. Homo erectus Using Tools
Re-creation of a Pleistocene setting in which Homo erectus use fire & stone tools

11. Neanderthals
Neanderthal (H. neanderthalensis) skeletons were first discovered in Germany’s Neander Valley.
Skeletons date back 200,000 years.
Massive brow ridges with protruding nose, jaws, and teeth.
Heavily muscled.
Culturally advanced.
Manufactured variety of tools.

12. Reconstructed Neanderthal skull
characterized
by prominent heavy brow ridges and week chin

13. Neanderthals (190,000 – 27,000 yrs ago)
Flaked stones that fit in wood handles.
Buried their dead with spices and bedding.
Built sturdy huts.
Made flutes!
A flute formed from a femur & 4 remaining holes.

14. Cro-Magnons – Homo sapiens
Oldest fossils to be designated H. sapiens.
Modern humans who entered Asia and Europe from Africa 100,000 years ago.
Made advanced stone tools.
Accomplished hunters.
Hunted cooperatively.
First to have complex language?

15. Homo Floresiensis (hobbits)
- one meter high
- lived in Flores
12,000 yrs ago
- Upright posture
- 380 cc cranial
size (like a chimp)

16. The shapes & sizes of hominid heads can be seen to evolve with time.

17. Australopithecus vs. Modern
Australopithecus, 4-3 myrs ago
Modern human
Chimpanzee

18. Cranial Comparisons
Homo Erectus
Neanderthal
Homo Sapiens

19. Hominid Evolution Review
Increase in brain size over time
Smaller jaw size over time
With larger brain came tool use and eventually language