Habitat Selection and Spatial Distribution Flashcards
What makes a good habitat?
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)
Name overall factors for habitat selection
- availability of resources
- risk of predation
- want resources high, predation low
What are some examples of availbility of resources animals look for?
food, mates, shelter, competition
Describe the conflict of needing: resources can be kept high and predation kept low
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
Name 2 models that predict who disperses
- Differences in the competition for mates and resources model
- Differences in competition between parents and offspring model
Differences in the competition for mates and resources model
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?
Differences in competition between parents and offspring model
involves First come, first serve hypothesis and Oedipus hypothesis
First come, first serve
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)
Oedipus hypothesis
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)
Oedipus hypothesis is regards to monogamy
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
Oedipus hypothesis in regards to polygyny
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
Poplar Aphid example
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)
Name pros and cons of Territoriality
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
Describe the experiment of Speckled Wood Butterfly
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
Payoff Asymmetry Hypothesis
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)
Dear Enemy Effect
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
Describe how a crab avoids dear enemy effect
Perform intimidation to avoid wasting energy on vigilance
Gang up on intruder
Stage of territorial disputes
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
Name animals who use strength or pushing competition in second stage of territorial disputes
elks, rams (shoving horns and antlers against each other), fishies(THEY ARE KISSIN)
Describe examples of visual displays
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
In what ways can an animal avoid territorial disputes?
- choose habitat with little to no competition
How does an animal’s behavior change as a result of the Dear Enemy Effect?
- they have increased vigilance
- vigilance will not lessen until taking control of territory
What options do animals have if they do not secure the most ideal habitat location?
- 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
Under what conditions might you expect an animal to engage in physical fighting as opposed to a lesser form of aggression?
- 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
What does the Competition for mates and resources model predict related to the dispersal behaviors of males and females?
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?
How does the payoff asymmetry hypothesis predict the amount of effort an animal might display to secure a 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)
