Lecture 10 - introduction to human evolution and how we study it

Question 1

Why study human evolution?

Answer 1

• only 1 species of homo

- many things in this 1 lineage - sentient, language, tool use

Question 2

how do we study human evolution?

Answer 2

• start with temporal and spatial framework

- last 7 million years (top of miocene)

Question 3

what time periods does the study of human evolution cover?

Answer 3

miocene, pliocene, pleistocene, holocene

Question 4

what are some of the dating methods used in studying human evolution?

Answer 4

• radiopotassium dating - 100,000 years then back through time
• optical dating - 100 - 1 million years back
• fission track - 1000 - deeper time

Question 5

added complexity of glacial events

Answer 5

• last 7 million years went from green house world to ice house world
• ice house world = unstable due to variation in ice cover and therefore sea levels

Question 6

last glacial maximum

Answer 6

18,000 ya

• colder
• ice sheets spread northwards and southwards dramatically - covering N. America and N. Europe
• rapid ice sheet change = rapid sea level change

Question 7

middle miocene

Answer 7

14mya
little ice
high sea level
*less ice = higher sea level

Question 8

Reconstructing environments:

Answer 8

use varves from lakes - annual- measure pollen and spores - tell how much grass, trees etc present

Question 9

evidence from living organisms:

Answer 9

• v poor fossil record - humans live inland - harder to fossilise, small number of them
• teeth and jaws most commonly fossilised as most durable
• skulls rarely preserved - when pieced together assumptions on how it should be are made = bias

Question 10

evidence from archeology:

Answer 10

• tools
• fires - charcoal
• cave paintings and statues - show more advanced behaviour
• symbolic burials - suggest social hierarchy

Question 11

primates:

Answer 11

700 species classified into 4 groups

Question 12

what are the four groups of primates?

Answer 12

1. prosimians: lemurs, tarsiers, bush babies
2. new world monkeys: marmosets, spider and howler
3. old world monkeys: baboons, colobus, macaques
4. hominoids: all apes including humans

Question 13

what are anthropoids?

Answer 13

all monkeys and apes

Question 14

what are hominoids?

Answer 14

apes and humans

Question 15

what are hominins?

Answer 15

humans

Question 16

what is the KT boundary?

Answer 16

the point between the cretaceous and the tertiary periods

Question 17

what happened 50ma?

Answer 17

• primates with modern aspects evolved
• adaptive radiation of primates
• anthropoids evolved in africa

Question 18

20ma?

Answer 18

hominoids in Africa

Question 19

18ma?

Answer 19

• hominoids migrate into Asia as Asia/Africa collide

- adaptive radiation of hominoids in Asia

Question 20

10ma?

Answer 20

asian hominoid migrates back into Africa - ancestral to all later hominids (including hominins)

Question 21

what is the name of the group when it is believed tarsiers are the closest related to anthropoids?

Answer 21

Omomyid group

Question 22

what is the name of the group when it is believed lemurs and lorises are the closest related to anthropoids?

Answer 22

Adapid group

Question 23

what are the 2 groups of apes?

Answer 23

gibbons (lesser apes) and hominids (great apes)

Question 24

how many species of gibbon are there?

Answer 24

18

Question 25

how many species of hominids are there?

Answer 25

7 - 2 orangutan, 2 gorilla, 2 chimpanzee, 1 human