Lecture 13

Question 1

How does biology differ from math

Answer 1

1. highly parallel, no obvious best teaching order
2. life on earth had unique history, large measure of chance mixed in
3. a different planet would have different biology, but not math

Question 2

What would happen if aliens visited other Earth-like planets

Answer 2

1. none would have same history (no matter how similar physical and chemical conditions)

Question 3

What does evolution mean

Answer 3

‘unfolding’

Question 4

How do stars evolve

Answer 4

birth (large and dense enough that gravity ignites nuclear chain reactions) to death (when fuel used up)

Question 5

How does evolution with stars differ from lifeforms

Question 6

How did Charles Darwin differ from others and thus is the most famous

Answer 6

none wrote as extensively, as carefully, or with as much insight

Question 7

where was Darwin’s theory of evolution published? what did it consist of

Answer 7

The Origin of Species
- 5 main parts
(never used the word evolution, just evolve at the end)

Question 8

What kinds of things did Darwin do as a child

Answer 8

loved natural history and outdoors
- collected insects, birds, plants, rocks

Question 9

What kind of science was of debate during Darwin’s undergrad? and Tenets of this new science?

Answer 9

geology… of debate
1. world is ancient and constantly changing
2. ongoing change in planet’s landforms/lifeforms = steady, gradual, observable

Question 10

What was the prevailing belief in England at the time

Answer 10

Earth was relatively young (6000 years previously)… Great Chain of Being

Question 11

What was the name of the sailing vessel by British Admiralty?

Answer 11

HMS Beagle
- chart coastline of South America

Question 12

What was Darwin’s unpaid job on the Beagle

Answer 12

naturalist

Question 13

What did Darwin develop while on the Beagle

Answer 13

3. common descent - every group of organisms descended from a common ancestor, with all lifeforms tracing back to single origin
4. new species form gradually and steadily according to observable processes still in operation, happens as populations adapt to surroundings
5. natural selection - mechanism of adaption whereby isolated populations evolve into new forms.

*Descent with modification

Question 14

How many books did he write, which one made him famous

Answer 14

10 books after Voyage of the Beagle - made him famous

Question 15

What allowed him to be wealthy and devote his time to writing and study?

Answer 15

Sizeable inheritance and investment in railroad stocks

Question 16

What was Darwin’s likely long term ailment

Answer 16

Chaga’s disease, trypanosome transmitted by a ‘kissing bug’ which he was bitten while in South America

Question 17

How many of his kids died young

Answer 17

2 infants, 1849 a 10 year old daughter (scarlet fever)…

Question 18

What is natural selection

Answer 18

biological process… holds when certain conditions hold

Question 19

What are the conditions needed to hold for erosion?

Answer 19

1. substrates have differential hardness
2. there is movement of wind, water, or ice

Ubiquitous… = important = always at work

Question 20

What are the conditions needed to hold for natural selection?

Answer 20

1. variation
2. inherited
3. traits affect survival and/or reproduction (fitness)

*ubiquitous = important = always at work

Question 21

What other important geological processes are there

Answer 21

• big, large, scale, slow phenomena
• sudden, violent events
  –> shaped planet

Question 22

How does geography impact evolution

Answer 22

create places where unique lifeforms evolve

Question 23

How does planetary scale catastrophes impact lifeforms

Answer 23

• occasionally occurred and changed dominant flora and fauna of the planet suddenly and completely

Question 24

What are the 5 parts of Darwin’s theory

Answer 24

1. world is ancient and constantly changing
2. ongoing change of planet’s lifeforms is steady and gradual
3. common descent
4. new species also form gradually and steadily
5. natural selection

*descent with modification

Question 25

Draw a monophyletic group

Question 26

Draw a polyphyletic group

Question 27

Draw a paraphyletic group

Question 28

Who pursued idea of peppered vs dark moths?

Answer 28

HBD Kettlewell…
First good quantitative demonstration of natural selection operating in nature

Question 29

What is directional selection draw it

Answer 29

favours one extreme phenotypes, causing average phenotype in population to change in one direction

Question 30

What is stabilizing selection and draw it

Answer 30

Favours phenotypes near the middle of the range of phenotypic variation, maintaining average phenotype

Question 31

What is Disruptive selection and draw it

Answer 31

Favours extreme phenotypes at both ends of the range of phenotypic variation

Question 32

What is Balancing selection, draw it

Answer 32

No single phenotype is favoured in all populations of a species at all times

Question 33

What are three ways of understanding what is a species

Answer 33

1. biological species concept - one or more actually or potentially interbreeding natural populations, reproductively isolated from other such groups
2. morphological species - based on differences in morphology
3. Lineage species - a terminal twig on a phylogenetic tree