Paleoanthropology and bipedalism

Paleoanthropology and bipedalism

In the final 1/3 of the class we will cover:

-Changes that have happened along the human lineage over the last 7-8 million years

-Lots of different hominin species that existed over that time even on extinct lineages (i.e. not all hominins led to us, most did not)

-Where hominins have been found and what that tells us about human evolution

-Different types of fossil deposits and dating methods

-How those species can be grouped together to help us understand how humans evolved

-Which hominins led to humans and what makes us different from other hominins

Question....

Multiple Choice

What did the 7-8 my old ancestor of humans and chimpanzees likely look like?

• like a chimpanzee

• a biped with hair covering it's body

• it had short, human-like arms

• it had a large brain like humans

Helpful techniques for understanding hominins and hominin evolution

-Think of hominin evolution in 3 phases based on time period (Miocene, Pliocene, Pleistocene).

-These time periods are characterized by different climates and, to a great extent, different kinds of hominins

Questions....

Multiple Choice

During which epoch did hominins first appear?

• Pleistocene

• Holocene

• Miocene

• Pliocene

Multiple Choice

Which epoch was the warmest and wettest period?

• Pliocene

• Holocene

• Miocene

• Pleistocene

Multiple Choice

Which time period was the coolest?

• Pliocene

• Holocene

• Miocene

• Pleistocene

Multiple Choice

Which time period did most australopithecines exist during?

• Pliocene

• Holocene

• Miocene

• Pleistocene

Multiple Choice

Which epoch was the most stable in terms of climate

• Pliocene

• Holocene

• Miocen

• Pleistocene

Mosaic evolution: these changes didn't all happen at the same time or change at the same rate

-bipedalism happens early on

-canine reduction happens early on

-modern limb proportions happen later

-brain size increase happens very late

-flat, human-like face happens very very late

-even the change with bipedalism happened at different times

****Sometimes the changes were gradual, and sometimes they happened rapidly

Questions....

Multiple Choice

Which changes happen over evolutionary time?

• canines get smaller

• brain gets larger

• face gets flatter

• hominins get taller

• all of these

Multiple Choice

All of the changes that make us human happened gradually over 7 million years and those changes occurred at the same time

• true

• false

Questions....

Multiple Choice

Which region is the best for dating fossils?

• east Africa

• south Africa

Multiple Choice

Which region relies more on biostratigraphy?

• east Africa

• south Africa

Multiple Choice

Which region contains the Rift Valley?

• east Africa

• south Africa

I'm not going to go in depth here because most of you have yet to take the Week 12 quiz

Questions....

Multiple Choice

When hominins became bipedal _____.

• our pelvis got narrower

• our pelvis got taller

• our pelvis got wider

• our pelvis stayed the same

Multiple Choice

All of the following happened when hominins became bipedal EXCEPT_______.

• our big toe became inline with the rest of our toes.

• our femur angled in toward the knee

• our spine curvature changed

• our foramen magnum moved to the back of the skull

• our feet developed arches

Multiple Choice

Do we have a bipedalism lab coming up?

• Yes, of course. I was already aware of it.

• No

This week we have less assignments, but you still need to turn them in.

Wednesday and Thursday are instructional breaks, but if you're behind, I would recommend using that time to get caught up

We have less than 4 full weeks of classes left.