Evolutionary Game Theory: John Maynard Smith

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Questions and Answers

What is the main concept discussed in evolutionary game theory?

Teleology

Evolutionary stable strategy (correct)

Natural selection

Frequency dependence

What is the role of frequency dependence in evolutionary game theory?

It dictates the decisions made by migrating geese.

It causes aggressive behavior in hawkish individuals.

It leads to teleology and preconceived outcomes in organisms.

It determines the fitness of an organism based on its phenotype frequency in the environment. (correct)

What does the term 'evolutionary stable strategy' refer to?

The decisions made by migrating geese to fly in pack environments.

The aggressive behavior of hawkish individuals in a population.

A strategy that all members of a population adopt, making it invadable by a mutant through natural selection. (correct)

The teleological planning of specific outcomes by organisms.

In evolutionary game theory, what are the average values of payoffs called?

Expectations Signup and view all the answers

What is the central idea regarding fitness in evolutionary game theory?

Fitness is dictated by the frequency of an organism's phenotype and other phenotypes in the environment. Signup and view all the answers

According to John Maynard Smith, what does evolutionary game theory suggest about the decisions made by organisms?

Organisms are not trying to do a specific plan but are being selected based on the plan they follow. Signup and view all the answers

In the context of evolutionary stable strategies, when is the hawk favored?

When the value increases Signup and view all the answers

What is the property of organisms to produce distinct phenotypes in response to environmental variation called?

Phenotypic plasticity Signup and view all the answers

In the diagram showing the fitness of different lizards, which color accumulates as oranges hold smaller territories?

Blue Signup and view all the answers

What is an example of a conditional reproductive strategy mentioned in the text?

Cooperative breeders Signup and view all the answers

What does Lrs represent in the context of reproductive strategies?

Number of chicks raised Signup and view all the answers

What determines the sex ratio in Atlantic silverside fish?

Temperature and place Signup and view all the answers

What can parasitoid wasps control to influence sex ratio?

The decision to birth diploid females or haploid males Signup and view all the answers

In high-quality territories, what do female offspring do in terms of cooperative breeding?

They help raise kids Signup and view all the answers

What does the property of organisms to produce distinct phenotypes depend on?

Environmental variation Signup and view all the answers

What do some male Atlantic Silverside fish do when they encounter a large number of female eggs on hosts?

They increase laying male eggs Signup and view all the answers

Under what circumstance does breeding become the best strategy for birds?

When helping relatives in another nest results in more surviving relatives Signup and view all the answers

Under what condition is it not great but favorable for individuals to have their own chicks?

When individuals must re-nest due to predation pressures Signup and view all the answers

What is the purpose of the sex ratio bias mentioned in the text?

To increase the number of female eggs in high-quality territories Signup and view all the answers

What strategy is recommended in the Prisoner's Dilemma pay off matrix for cooperating and defecting?

Defect if played once, cooperate if iterated Signup and view all the answers

In the context of vampire bats, what benefit does receiving blood give when starved?

Provides large weight gain Signup and view all the answers

What role does kin selection play in determining whether a bat will receive blood from another bat?

Plays a strong role in determining whether a bat will receive blood Signup and view all the answers

How do helpers affect reproductive success in territories?

Helpers increase reproductive success in high-quality territories and decrease it in low-quality territories Signup and view all the answers

What is the effect of good quality territory on the sex ratio bias?

Increases bias towards female eggs Signup and view all the answers

Study Notes

Evolutionary Game Theory Concepts

Focuses on strategic interactions among individuals where the success of a strategy depends on the strategies of others.
Emphasizes how evolutionary processes shape behaviors in competitive environments.

Frequency Dependence

Refers to the idea that the fitness of a phenotype depends on its frequency relative to other phenotypes in the population.
Can favor less common strategies, creating dynamic changes in population structure.

Evolutionary Stable Strategy (ESS)

A strategy that, if adopted by the majority of the population, cannot be invaded by a small group using an alternative strategy.
Stability arises from the ability of the ESS to maintain itself through its success against mutant strategies.

Average Payoffs

Known as "average values of payoffs," this term reflects the fitness benefits accrued by strategies across different scenarios in the population.
These averages inform how effective a particular strategy is over time.

Fitness in Evolutionary Game Theory

Central idea revolves around reproductive success and survival, where strategies that maximize fitness are favored.
Fitness is influenced by the interactions and outcomes of competing strategies within the environment.

Organism Decision Making

John Maynard Smith posited that evolutionary game theory indicates organisms make decisions based on the expected behaviors of others.
The concept of strategic choices plays a critical role in survival and reproduction.

Hawk Favorability in ESS

Hawks are favored in scenarios where resources are limited and competition is high, providing advantages to aggressive strategies.
This favorability occurs when the costs of conflict are outweighed by the potential rewards.

Phenotypic Variability

Known as phenotypic plasticity, it is the property allowing organisms to produce distinct phenotypes in response to environmental changes.
Enables adaptability and survival in varying conditions.

Coloration in Lizard Fitness Diagram

In the context of territory size, orange lizards dominate smaller territories, leading to a bias in their accumulation over time.
This impact on territorial behavior illustrates the relationship between phenotype and fitness.

Conditional Reproductive Strategy Example

A notable example is the alternative reproductive tactics in species where individuals may adjust their behavior based on environmental cues or population dynamics.
Such strategies showcase flexibility in reproductive success.

Lrs in Reproductive Strategies

Represents the life history strategy of reproductive investment, balancing the number of offspring with the quality and survival of those offspring.
A critical element in assessing reproductive success.

Atlantic Silverside Fish Sex Ratio

The sex ratio is determined by environmental factors and resource availability, affecting reproductive dynamics.
A significant aspect of population ecology.

Parasitoid Wasp Control

Parasitoid wasps can control their hosts' developmental outcomes to influence offspring sex ratios selectively.
This manipulation exemplifies strategic reproductive behaviors.

Female Offspring in High-Quality Territories

In premium territories, female offspring engage in cooperative breeding, enhancing survival rates and resource sharing.
This behavior illustrates group dynamics and social organization in reproductive strategies.

Dependency on Environmental Variation

The production of distinct phenotypes relies on environmental variations that pose different selective pressures.
A critical driver of evolutionary adaptations.

Male Atlantic Silverside Strategy

Males may adopt aggressive strategies when encountering abundant female eggs, showcasing competitive behaviors.
This tactic underscores the importance of resource access in reproductive success.

Breeding Strategy for Birds

Breeding becomes advantageous when competition for resources is low and environmental conditions are favorable.
Optimal strategies can shift based on ecological contexts.

Individual Chick Advantage

It may be beneficial for individuals to raise their chicks when external conditions provide secure habitat and resource availability despite the risks involved.
Balancing personal investment and survival plays a role.

Purpose of Sex Ratio Bias

Different strategies like sex ratio bias are employed to maximize reproductive success under varying ecological conditions.
These biases often reflect resource allocation amongst offspring genders.

Prisoner's Dilemma Strategy

The recommended strategy varies depending on payoff matrices, generally suggesting cooperation yields mutual benefits when reciprocated.
Cooperation often leads to higher overall payoffs in repeated interactions.

Vampire Bats Blood Donation

Starvation triggers benefits of receiving blood from other bats, enhancing survival chances in tough conditions.
Blood-sharing is an example of mutual aid and social behavior in challenging environments.

Kin selection affects the likelihood of receiving blood; bats are more inclined to assist relatives, boosting inclusive fitness.
Promotes cooperation among closely related individuals.

Helpers and Reproductive Success

Helpers in territories can increase the reproductive success of breeding pairs by assisting in offspring care and resource management.
This cooperative strategy is beneficial for population stability.

Good Quality Territory Impact

High-quality territories can influence sex ratio bias towards females, enhancing overall reproductive output in optimal environments.
Reflects the resource-based dynamics in reproductive strategies.

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Description

Learn about evolutionary stable strategies derived from game theory, with a focus on the work of John Maynard Smith, the father of game theory in biology. Explore how organisms make decisions based on migrating geese and traits dictated by their choices in their environment.