Animal Behavior 2

Front 1

What is Darwin's big idea?

Back 1

Evolution by natural selection

Front 2

Natural selection =

Back 2

process whereby some organisms in a species have certain inherited variations that give an advantage over others

Front 3

What are the 3 key components of natural selection?

Back 3

Variation -physical, physiology, behavior within a species. From MUTATION or gene flow (random occurances)


Variation is inherited - heritability = 0-1 (1 being exactly same). Beak size had high heritability. HERC2 vs Gey gene and eye phenotype

Differential survival and reproduction - some individuals leave more offspring due to food, shelter, mate competition and survival (predator avoidance)
These differences in success must be related to heritable differences

Front 4

Define fitness

Back 4

An individual's # of offspring surviving to reproductive maturity during its lifetime

Relative measure to specific population

Indirect measures include: #offspring born, #grandkids, resources controlled (territory, food), mates (mating opportunities, #mates, copulatory events)

Front 5

Natural selection is not the only mechanism for evolution! What are others?

Back 5

Genetic drift
- founder effect

Immigration
Emigration

Front 6

Selection is NOT always

Back 6

directional! There is no endpoint/goal

Front 7

3 types of natural selection

Back 7

Disruptive (two peaks form)
Stabilizing (narrow middle peak)
Directional (peak to right/left)

Front 8

GO OVER:

Back 8

Phylogenies!! (slide 19-37)
genetic drift
eye color example of what (heritability?)
slide 44 - must already have tree

Front 9

Define: species
What is speciation? Name 2 types

Back 9

Animals capable of interbreeding/evolutionary lineage

Evolutionary process leading to new species

Anagenesis - single lineage over time
cladogenesis - splitting 1 into 2 lineages

Front 10

Allopatric vs sympatric speciation

Back 10

Allopatric - barrier/isolation formed, 2 different species in reproductive isolation

Sympatric - error in genetic duplication that disables interbreeding

Front 11

How to study evolution of behavior?

Back 11

1) FOSSILS - difficult, rare - dinosaur brooding eggs --> behavior evolved to modern day birds. Also: locomotion (hips), diet (teeth - flat/sharp canines)

2) Map behavior onto an evolutionary tree - can't use behavior to create the tree

Front 12

What is adaptation?

Back 12

Characteristic that confers higher fitness to individuals than do the alternatives, a trait that has spread is spreading or is being maintained by natural selection

Adaptive value = contribution that a trait makes to fitness. Fitness = higher reproductive success

Front 13

How to test for current adaptive value

Back 13

Species analysis
Cross benefit analysis: For adaption - B>C
use indirect measures

example: long song preference of female starlings, despite energy expenditure

Front 14

Black headed gull mobbing - what are the costs/benefits

Back 14

Costs: energy + danger
Benefits: Mobbing is adaptive because it increases chances of egg survival (as shown in study)

Compared center to periphery of colony - less predation

Front 15

Widowbirds: what is the benefit of the long tail?

Back 15

To attract mates

Front 16

Historical analysis of adaptation

Back 16

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