Kin Selection Flashcards
What is Altruism?
a social action to increase the lifetime number of offspring of another individual at a cost to one’s own chances of survival and reproduction
What is Relatedness(r)?
the probability that a gene in one individual is present in another individual, due to the two individuals being related (kin).
What is Hamilton’s Rule?
mathematical equation to explain the conditions under which altruism can evolve
What does Hamilton’s Rule state?
A gene for altruism can spread if the benefit to the recipient (B) multiplied by the relatedness (r) exceeds the cost to the actor (C):
rB - C > 0
What view of evolution did Hamilton take?
a genetic-centric view
What does Haldane’s quote suggest?
Haldane’s quote suggests that individuals may be more inclined to make sacrifices for those who are closely related to them, highlighting the importance of kinship in altruistic behaviours.
What is Hamilton’s equation?
rB - C > 0
What does each letter stand for?
B-benefit to recipient (gain in the number of recipient’s offspring).
C-cost to the actor (loss in the number of actor’s offspring).
r- relatedness between actor and recipient: the probability that a gene in one individual is present in another individual
What is indiscriminate altruism?
occurs when individuals help others regardless of relatedness, often seen in species such as meerkats
How do Belding’s ground squirrels demonstrate kin recognition?
They exhibit behaviours that suggest they can recognise kin and preferentially direct altruistic behaviors towards them.
What are some behavioural examples of kin selection?
- Black-tailed prairie dogs give fewer alarm calls when no close relatives are present.
- Long-tailed tits preferentially help relatives over non-relatives.
How do Belding’s ground squirrels demonstrate kin recognition?
They exhibit behaviours that suggest they can recognise kin and preferentially direct altruistic behaviours towards them.
hat hypothesis was tested regarding facial recognition in paper wasps?
The “adaptive specialization hypothesis” suggests that facial recognition evolved as a specialized cognitive ability
How do facial recognition and kin selection relate in social wasps? What does this lead to?
-Social wasps, like Polistes fuscatus, exhibit facial recognition abilities that enhance their capacity to identify relatives,
-This leads to more effective kin-directed altruistic behaviors.
Cost-benefit analysis in altruism
A decision-making process where individuals weigh the benefits of helping others against the costs to their own reproductive success.
What role does alarm calling play in kin selection among prairie dogs?
Prairie dogs use alarm calls to warn group members of predators, with the frequency of calls often influenced by the presence of close relatives, demonstrating kin recognition.
What are the components of altruism in terms of cost and benefit?
Cost (C): The loss in the actor’s offspring
Benefit (B): The gain in the recipient’s offspring
Why can altruism evolve even if relatedness (r) is low?
Altruism can evolve if the benefits to the recipient are high enough relative to the costs incurred by the actor.
How does Kin recognition influence altruistic behaviour?
Kin recognition allows individuals to identify and preferentially help relatives, which can enhance inclusive fitness by contributing to the survival and reproduction of shared genes.
How do you calculate Hamilton’s Rule for wild turkeys?
- Determine benefit (b) and cost (c).
- Use the formula:
rB - C > 0
If true, helping behaviour is favoured.
What is the significance of alarm calls in black-tailed prairie dogs? What does this indicate?
They give fewer alarm calls when no close relatives are present, indicating a kin-based approach to altruism
What is inclusive fitness?
an individual’s reproductive success plus the reproductive success of their relatives, weighted by their relatedness
How do ecological conditions affect altruism? Why?
Poor ecological conditions may lead to increased cooperation and altruism as survival becomes more challenging
What is the difference between altruism and cooperation?
-Altruism: Costly behavior that benefits another individual
-Cooperation: Mutually beneficial actions that enhance the fitness of both parties.
Can altruistic behavior evolve without relatedness?
No, according to Hamilton’s rule, altruism can only evolve if social partners are related, as shown by the requirement that rB - C > 0 must hold true.
Behavioral evidence for kin selection
Observations that support kin selection theory, such as preferential helping of relatives, cooperative breeding, and alarm calls linked to relatedness.
Cost-benefit analysis in altruism
helping others against the costs to their own reproductive success.
