Selfishness + Altruism Flashcards
What are the three key components of natural selection related to behavior?
- Behavioural alternatives in the population
- Differences are (at least partially) heritable
- Some behavioural alternatives confer higher fitness payoffs than others
What is Group Selection theory?
Selection acts at the level of the group rather than the individual.
Example: Males don’t fight to the death as it would endanger the species.
What was Wynne-Edwards’ explanation for sterile worker ants?
Individuals restrict breeding to prevent over-exploitation of resources, allowing group selection to keep populations in check.
What was Lack and Williams’ argument against Group Selection?
Group selection is not an ESS (Evolutionarily Stable Strategy) and can be invaded by selfish individuals.
What happens when selfish individuals arrive in a population practicing reproductive restraint?
- Population of individuals practicing reproductive restraint
- Selfish individuals arrive (migration or mutation)
- The selfish individual genotype would soon spread.
What did Richard Dawkins propose in 1976 regarding selection?
Selection acts at the level of the gene; genes exist to propagate themselves, and organisms are simply vehicles.
What are some examples of cooperation in animals?
Baboons grooming, lions hunting, meerkats babysitting, honeybee workers feeding queens’ offspring.
What is altruism?
An act that benefits the recipient at a cost to the actor, where cost and benefit are defined in terms of fitness.
Why do females call more than males?
Females remain in their birth area, while males disperse to avoid inbreeding.
Females are more likely to call when near daughters, mothers, or sisters than when near cousins or non-relatives.
What is the primary context in which altruism occurs?
Most altruism occurs between relatives, as it has evolved to help kin.
What drives the behavior of selfish individuals?
Natural selection acts on individuals so they behave to maximize their own gene contributions to future generations.
How is relatedness defined?
Relatedness is the genetic similarity between two individuals relative to the population, measured as the proportion of alleles shared through common ancestry.
Who proposed the concept of kin selection?
Bill Hamilton, a mathematical biologist, proposed the concept of kin selection.
What is the significance of kin selection?
Genes can be passed on indirectly via non-descendent kin, and helping relatives to increase their fitness can be favored by natural selection.
What is Hamilton’s rule?
Hamilton’s rule states that altruism will evolve when r x B > C, where r is the relatedness between actor and recipient, B is the benefit to the recipient, and C is the cost to the actor.
What does ‘pay to stay’ refer to in the context of altruism?
Helping may increase the likelihood of being tolerated by the dominants in the territory, with cooperation enforced by aggression from dominants and potential eviction.
What are vampire bats known for?
Vampire bats are one of three bat species that feed on blood from cattle, horses, pigs, and birds.
How do vampire bats locate their food?
Vampire bats use heat sensors to locate capillary-rich skin.
What is the buddy system in vampire bats?
Within colonies, pairs of vampire bats form close bonds, roost together for many years, and help each other feed.
What happens if a bat fails to feed?
If a bat fails to feed, its buddy will feed it, even if they are unrelated.
Under what condition will bats feed each other?
Bats will only feed those they have roosted with for some time, allowing them to return the favor later.
