3.3.1 Natural Selection

• What is natural selection?

  Advantageous traits prevail
• Natural selection is the process by which organisms with advantageous traits survive and reproduce more effectively in their environment, leading to the prevalence of those traits
• Inheritable traits are passed on to offspring.
• What does variation refer to within a population?

  Differences in traits
• Advantageous traits lead to higher survival and reproduction rates
• What are genes in the context of natural selection?

  Instructions for traits
• Individuals with beneficial genes have higher fitness
• Genes conferring disease resistance increase survival chances.
• Why might aggression be a selected trait through natural selection?

  Securing resources or mates
• Aggressive male deer defend their territory to win mating opportunities
• What is the formula for measuring fitness in natural selection?

  \text{Fitness} = \frac{\text{Reproductive Success}}{\text{Average Reproductive Success \in Population}}</latex>
• Aggression is always beneficial for survival and reproduction.

  False
• Aggressive lions are more likely to defend their territories and win mating opportunities
• Why are male lions with higher levels of aggression more likely to succeed in defending their territories and winning mating opportunities?

  Greater fitness
• Fitness is calculated as the ratio of reproductive success to the average reproductive success in the population
• Aggression is always a beneficial trait in all environments.

  False
• Arrange the following examples of aggressive behavior in animals in order of their primary purpose:

  1️⃣ Territorial Defense

  2️⃣ Mate Competition

  3️⃣ Resource Acquisition
• What is the example of territorial defense provided in the study material?

  Male lions protecting territory
• For survival, aggression helps individuals secure resources and defend their territory
• Match the evolutionary mechanism with its effect:

  Natural Selection ↔️ Adaptation

  Genetic Drift ↔️ Random fluctuations

  Gene Flow ↔️ Introduction of new alleles

  Mutation ↔️ Generates new genetic variation
• What is the primary outcome of natural selection?

  Adaptation
• Within a population, individuals exhibit differences in their traits
• Inheritable traits can be passed on to offspring.
• What role does genetic variation play in natural selection?

  Allows beneficial traits
• Match the trait with its effect on fitness:

  Beneficial gene ↔️ High fitness

  No beneficial gene ↔️ Low fitness
• How does aggression increase fitness in male lions?

  Securing territory and mates
• Under what conditions is aggression likely to be favored by natural selection?

  Scarce resources or high competition
• Male lions with higher levels of aggression are more likely to defend their territories and win mating opportunities.
• The formula for fitness is Fitness = Reproductive Success / Average Reproductive Success in Population
• What are examples of aggressive behaviors in animals that demonstrate natural selection?

  Territorial defense, mate competition
• Match the aggressive behavior with its adaptive function:

  Territorial defense ↔️ Ensures resources and mating opportunities

  Mate competition ↔️ Determines who gets to reproduce

  Resource acquisition ↔️ Guarantees access to essential resources
• Steps in the adaptive functions of aggression for survival and reproduction:

  1️⃣ Securing resources

  2️⃣ Defending territory

  3️⃣ Competing for mates

  4️⃣ Boosting fitness
• What are the key roles of aggression in survival and reproduction?

  Securing resources, defending territory
• Aggression for territorial defense helps ensure access to food and shelter.
• Aggression in mate competition directly boosts an individual's fitness
• Match the benefit of aggression with an example:

  Resource acquisition ↔️ Hyenas competing for food

  Territorial defense ↔️ Male lions protecting territory

  Competing for mates ↔️ Male deer fighting for mating rights
• What are the four mechanisms of evolution discussed in contrast with natural selection?

  Genetic drift, gene flow, mutation
• Natural selection leads to adaptation by environmental pressures favoring advantageous traits.
• Genetic drift is a random process that reduces genetic diversity
• What is the effect of gene flow on allele frequencies between populations?

  Introduces new alleles