evolution lecture 1

Question 1

what was Darwin’s book in 1859 called?

Answer 1

the origin of species

Question 2

what were the thoughts surrounding biology, before evolution?

Answer 2

• species were unchanging
• ladder of increasing perplexity
• more complex, the closer to divine/ god

Question 3

Linneaus biological classification 1758

Answer 3

hiearchy of nested sets

- groups within groups

Question 4

what is palentology based on?

Answer 4

Fossils

Question 5

what did lamark see because of fossils?

Answer 5

progression in species

- suggested forms come into being by being modifications of previous forms

Question 6

the two parts to Lamarks idea?

Answer 6

1) pattern
- each of the many seperate lineages of independant
origin strive to perfection/ complexity

2) Process/ mechanism
- “use and disuse of parts”

Question 7

what is “larmarkism”?

Answer 7

the inheritance of acquired characters

Question 8

In general, what were Lamark’s ideas?

Answer 8

• a poor fit to biological classification
• a meachnism that was not well supported
• however, it explains the variation among species

Question 9

What did Darwin do before all this biological ideas and his book?

Answer 9

go to medical school

he was a medical school drop out

Question 10

what were Darwins two main ideas?

Answer 10

1) the PATTERN of evolution

2) the PROCESS of evolution

Question 11

what was darwins pattern evolution idea?

Answer 11

living things united in a single branching tree of relationships

• new lineages constatnly being created by existing ones being splitted in two
• “descent with modification” Species A and B are similar because they share common ancestor
• but A and B differ because of the changes after divergence from their last common ancestor

Question 12

what was Darwin’s process of evolution idea?

Answer 12

• evolution happens mostly because of natural selection

Question 13

What are the ingredients to natural selection?

Answer 13

• Heritable variation
• Excess production
• Differential success

natrual selectino thought heritable excess was differential success

KEY POINT: individuals of a species belong to populations

Question 14

what is heritable variation?

Answer 14

• individuals are born with many varying traits

- many traits can be passed on to offspring from parents

Question 15

what is excess production?

Answer 15

• in any population, more offspring are produced than needed

Question 16

what is differential success?

Answer 16

-excess production leads to competition
- because of their differing traits, individuals will have varying levels of success
- some individuals will produce more offspring because of their traits being an advantage
This is the concept of FITNESS
- favourable traits increase in frequency in the population
- evolution

Question 17

What does natural selection act on?

Answer 17

existing variation (it does not generate variation)

Question 18

how does variation happen?

Answer 18

mutations in genome

Question 19

what showed the plausibility of natural selection?

Answer 19

artificial selection

Question 20

what does natural selection over time result in

Answer 20

adaptation!

- adaptive evolution