Wk-11 Human Evolution

Question 1

Evolution - natural selection peppered moth

Species are v?
Increase in survival / reproduction in some species due to favourable environment
This results in increase in offspring with the f? v?
Least favourable traits p?

Answer 1

Variable
Favourable variables
Perish

Question 2

Gene mutations:

Create huge v?
Mutations occur from errors in copying ?
Alters g? and may create novel a?
New a? may result in changed p?

Answer 2

Variability
DNA
Genome ,alleles
Alleles , phenotype

Question 3

Phylogenetic tree = ?

Demonstrates the evolutionary relationship between species descending from a c? a?

Answer 3

Evolutionary tree

common ancestor

Question 4

Gene flow: migration

Is the transfer of 1 gene variant from 1 population to another.
Predominantly occurs from migration ?/? population
This results in h? a combination of genes from 2/more distinct populations.

Answer 4

Into/out

Hybridisation

Question 5

Genetic drift- small populations

Random changes in gene variant frequency
A random change in small populations > leads to F? Effect
Results in loss of some g- v- in future generations

Answer 5

Founder effect

Gene variants

Question 6

Founder effect: reduced variation

Loss of genetic variation in a new small population
Not all gene variants are present

Original population > possible founder populations
Seen in small culturally i? groups
Small populations and in-? increase probability inheriting diseased a?

Answer 6

Isolated groups

Inbreeding ,alleles

Question 7

Human evolution : hom?

Darwin ? ? Theory
Hom? (similarities between organisms)
Mammals have anatomical h? Comparative genomics (same number of genes –,000 and genome size, - billion)
Human and mouse genes -5% similar
Human DNA and chimpanzee DNA -% different

Answer 7

Homology 
Common ancestor 
Homologies 
Homologies, 21,000 , 3 billion 
85%, 2%

Question 8

Human evolution:

Humans derived from h? (Primate Evolution)
What are the 4 major events in evolution?
1. T? Trees> land
2. B? All 4’s > 2 legs
3. E? Increase brain capacity
4. C? Society more complex

Answer 8

Hominids

1. Terrestrialism
2. Bipedalism
3. Encephalisation
4. Civilisation

Question 9

Bipedalism (Lucy)

1st change differentiated apes and humans other mammals
Gradual change in p? and limbs - ? Million years ago (Lucy)
Reduced c? ability
Increase w? and r? motions

Answer 9

Pelvis, 6 million
Climbing
Walking/running

Question 10

Hominids: 6 evolutionary stages

1. Austral-?
2. Homo?
3. Homo er? Homo eg?
4. Archaic homo s?
5. Homo s? Nean?
6. H? S?

Answer 10

1. Australopithecines
2. Homohabilis
3. Homo erectus/ homo ergaster
4. Archaic Homo sapiens
5. Homo sapiens neanderthalensis
6. Homo sapiens

Question 11

1. Australopithecines
   4- ?.6 million years ago
   1- ?.5 m tall
   Capable of bi? (Lucy)
2. Homo habilis
   ?.3 - 1.4 million years ago
   Increase ? Size
   1.2 - 1.6 m tall

Answer 11

1.6
1.5
Bipedalism

2.3
Brain

Question 12

3. Homo erectus / homo ergaster
   1.8 million ya to 1-0 thousand years ago
   1.6 - 1.? m tall
   Increase ? size continues
   Use ? Tools
   Modern human p?
   Migration out of ?

Answer 12

150,000
1.8 m 
Brain 
Stone 
Phenotype 
Africa

Question 13

4. Archaic Homo sapiens 
300 to ?00 thousand ya
Large brain 
Decrease height/size 
Increase ? and culture structure

Answer 13

100

Society

Question 14

5. Homo neanderthalensis
   130 to ?0 thousand ya
   More robust , similar to modern ?
6. Homo sapiens
   ?00,00 ya to ?
   Increase brain
   Extensive society and culture structure

Answer 14

30,000
Humans

200,000 , present

Question 15

Migration theories:

1. Out of Africa
2. Multi regional

Genetic evidence supports ?
Second wave of modern humans 150 to ?00 thousand ya replaced previous migrants

Answer 15

Out of Africa

200,000