Habitat Selection and Spatial Distribution

Question 1

What makes a good habitat?

Answer 1

Availability of resources(Food, mates, shelter, etc.)

Risk of Predation

Location of relatives (Minimize risk of inbreeding, Minimize competition with kin for resources; do not want to compete against own genetics)

Question 2

Name overall factors for habitat selection

Answer 2

• availability of resources
• risk of predation
• want resources high, predation low

Question 3

What are some examples of availbility of resources animals look for?

Answer 3

food, mates, shelter, competition

Question 4

Describe the conflict of needing: resources can be kept high and predation kept low

Answer 4

Can’t secure most ideal habitat?
Choices can have equal pros and cons

Stay and tough it out; Could be killed, no guarantee waiting will bring better payoff

Pack up and leave; Lots of risks for unknowns, uses lots of resources

Question 5

Name 2 models that predict who disperses

Answer 5

• Differences in the competition for mates and resources model
• Differences in competition between parents and offspring model

Question 6

Differences in the competition for mates and resources model

Answer 6

Competition for Mates: from male perspective

More likely to defend territory, be monogamous; females go
Do not defend territory (since move around a lot), be Polygynous (male w/mult. females); females stay
Make defense system

Resources: from female perspective

Matrilineal lineages, females stay; males go; resources abundant
Matrilineal lineage – females go; male stay; resources liminted
Resources good? Competition low?

Question 7

Differences in competition between parents and offspring model

Answer 7

involves First come, first serve hypothesis and Oedipus hypothesis

Question 8

First come, first serve

Answer 8

Presence of father determines who goes and who stays
Present: all females need to go (prevent risk of inbreeding); male stay
Absent: females stay; males go (prevent risk of inbreeding with siblings)

Question 9

Oedipus hypothesis

Answer 9

Consider monogamy, polygyny, as well as option for care of their offspring(care for own or leave young for parents to care for); third factor birds and mammals under consideration)

Question 10

Oedipus hypothesis is regards to monogamy

Answer 10

Young male birds: are they in competition with parents? No

Will females stay? No, prevent inbreeding with siblings and parents will not raise any young laid in their nest(prefer to raise own instead of others)

Male mammals should be able to stay since in no competition with father; Female mammals will stay, since they are not in competition with mother for resources

Male and female mammals will cancel each other out though!! If they both stay, inbreeding happens; SO THEY WILL BOTH ACTUALLY GO

Question 11

Oedipus hypothesis in regards to polygyny

Answer 11

Young male birds stay or go? Go! Lots of competition between males
Young females go!
Male mammals will go; in competition with own father and will search elsewhere
Female mammals will stay; they need to take care of own young because of lactation

Question 12

Poplar Aphid example

Answer 12

Cottomwood poplar tree:
Secretes type of substance called gall to protect eggs of aphids
Aphids want to lay closest to peniole(point of stem end and leaf begin)

Question 13

Name pros and cons of Territoriality

Answer 13

Benefits: Monopolize on resources

Cons: Constantly defending territory; can cause injury and waste of energy

Less flexibility for movement

Have increased levels of testosterone, correlated with decreased level of immune functon; more likely for disease, illness, death
Increased testosterone leads to poor parental organisms

Question 14

Describe the experiment of Speckled Wood Butterfly

Answer 14

Experiment: let butterfly find habitat it liked, then captured it

Released new butterfly into area and then released original back into habitat

Followed pattern seen in other experiments; original male eventually takes habitat back

However, when done again, the original was held back longer and the new butterflies/intruder won dispute

Intruder winning due to payoff asymmetry hypothesis

Question 15

Payoff Asymmetry Hypothesis

Answer 15

organism with more interest in territory will win establishing residence in habitat

Organism who values resources more will fight more for it

(Think: you will spend more time looking for wallet than pencil; more interested in one than the other)

Question 16

Dear Enemy Effect

Answer 16

Starts with an increase in vigilance (Some organisms try to avoid this in the first place, can take up way too much energy! (like crab example))

Intruder will find territory not previously occupied that is not already owned

Once intruder claims territory not owned by anyone else, vigilance decreases/slows down

Question 17

Describe how a crab avoids dear enemy effect

Answer 17

Perform intimidation to avoid wasting energy on vigilance
Gang up on intruder

Question 18

Stage of territorial disputes

Answer 18

First stage includes avoidance of dispute within itself, wastes energy, or displays

Will have visual displays and auditory displays

Second stage includes pushing or strength competition

Third stage includes fighting

Question 19

Name animals who use strength or pushing competition in second stage of territorial disputes

Answer 19

elks, rams (shoving horns and antlers against each other), fishies(THEY ARE KISSIN)

Question 20

Describe examples of visual displays

Answer 20

Done in first stage of territorial disputes

Anole with dewlap
In female and male, bigger in male
Males use this to attract females
Also sign of intimidation by showing dewlap

Betta fish
Males extremely territorial
Fan out fins

Question 21

In what ways can an animal avoid territorial disputes?

Answer 21

• choose habitat with little to no competition

Question 22

How does an animal’s behavior change as a result of the Dear Enemy Effect?

Answer 22

• they have increased vigilance
• vigilance will not lessen until taking control of territory

Question 23

What options do animals have if they do not secure the most ideal habitat location?

Answer 23

• tough it out and risk extinction in habitat
• move elsewhere for better habitat factors and resources, risk energy/vulnerability with this for no guaranteed payoff

Question 24

Under what conditions might you expect an animal to engage in physical fighting as opposed to a lesser form of aggression?

Answer 24

• when challenged by another species, when the value of the resource equals the cost of keeping the resource
• when the value of the resource is greater than cost of keeping the resource

Question 25

What does the Competition for mates and resources model predict related to the dispersal behaviors of males and females?

Answer 25

Competition for Mates: from male perspective
- More likely to defend territory, be monogamous; females go
- Do not defence territory(since move around a lot), be Polygynous(male w/mult. females); females stay
- Make defense system

Resources: from female perspective
- Matrilineal lineages, females stay; males go; resources abundant
- Matrilineal lineage – females go; male stay; resources liminted
- Resources good? Competition low?

Question 26

How does the payoff asymmetry hypothesis predict the amount of effort an animal might display to secure a habitat?

Answer 26

Organism who values resources more will fight more for it

(Think: you will spend more time looking for wallet than pencil; more interested in one than the other)