What is the main effect of overpopulation on animal populations?

• A. Decreased genetic variation
• B. Increased competition for limited resources
• C. Enhanced cooperation among all individuals
• D. Immediate extinction of the species

Answer: (B)

Verified step by step guidance

1. Understand the concept of overpopulation: Overpopulation occurs when the number of individuals in a population exceeds the carrying capacity of their environment, leading to resource scarcity.
2. Analyze the options provided: Evaluate each answer choice to determine its relevance to the effects of overpopulation on animal populations.
3. Option 1: 'Decreased genetic variation' - This is not directly caused by overpopulation. Genetic variation is influenced by factors like mutation, gene flow, and genetic drift, not population density.
4. Option 3: 'Enhanced cooperation among all individuals' - While cooperation can occur in some species, overpopulation typically leads to competition rather than widespread cooperation.
5. Option 4: 'Immediate extinction of the species' - Extinction is a long-term consequence and not an immediate effect of overpopulation. The most direct and immediate effect is 'Increased competition for limited resources,' as individuals must compete for food, water, shelter, and other necessities.