Selective Pressures

Question 1

What is a selective pressure?

Answer 1

Environmental factor that affects survival

Selective pressures can include factors like predation, competition, and environmental changes.

Question 2

What controls population in a bottom-up model?

Answer 2

Resource availability

In bottom-up control, the abundance of resources determines the population size of consumers.

Question 3

What controls population in a top-down model?

Answer 3

Predators

In top-down control, the presence and population of predators regulate the size of lower trophic levels.

Question 4

What are density-dependent factors?

Answer 4

Factors that affect population based on size

Examples include disease, competition for resources, and predation.

Question 5

What are density-independent factors?

Answer 5

Factors that affect populations regardless of size

Examples include natural disasters, climate changes, and human activities.