Population Ecology

Population Ecology

• Population ecology is the study of factors affecting population size and composition, focusing on births, deaths, immigration, and emigration.
• Population ecology is important for understanding human impact on natural resources and for conservation and sustainability efforts.

Key Concepts and Vocabulary

• Demography is the study of statistics related to births and deaths within populations.
• Population growth can be exponential, meaning rapid growth until limited by resources, understanding limitations is important for both human and natural populations.

Factors Affecting Population Growth

• Population Growth Formula: Growth = B + I - D - E (Births (B), Deaths (D), Immigration (I), Emigration (E))
• Regulating Factors: Food and habitat availability, mate availability and competition (both interspecific and intraspecific), disease, predation, and climate factors.

Carrying Capacity

• Carrying capacity is the point at which a population can no longer grow due to limited resources.

Food Chain and Food Web

• Food chains are sequences of energy transfer from producers to apex predators.
• Examples of trophic levels include producers, primary consumers, secondary consumers, etc.
• Food webs are complex networks of interconnected food chains linking species within an ecosystem.

Predator-Prey Dynamics

• Predators regulate prey populations and vice versa.
• Population cycles occur between predator and prey (e.g., lynx and hare).
• Predation affects population growth by contributing to mortality rates.
• Both predators and prey can become linked over time.
• A lab scenario involves beans as prey and students as predators.

Human Impact on Population Ecology

• Human consumption impacts resources: energy (fossil fuels, climate change), water (overdrafting natural springs), and space (urban sprawl leading to habitat destruction).
• Urban areas, like Mexico City, face overpopulation challenges.

Investigation 1: Predator-Prey Relationships

• An experiment involving 100 individuals of each prey species (beans) spread in a 5x5m hunting area.
• Predators have 60 seconds to consume as many prey as possible.
• Predators must consume at least 20 prey items to survive.
• If a predator dies, it becomes the predator species that consumed the most prey in the previous round.
• Before starting the next round, surviving prey reproduce (each surviving bean gains one offspring).
• Carrying capacity for each species is 800 individuals.

This quiz explores key concepts in population ecology, including factors that affect population size and dynamics such as births, deaths, immigration, and emigration. It emphasizes the significance of understanding these factors in conservation and sustainability efforts. Test your knowledge on demography, population growth, and carrying capacity.