Final answer:
Density-dependent factors, such as predation, competition, and disease, and density-independent factors, such as weather and natural disasters, are natural selection factors that affect animal populations.
Step-by-step explanation:
Natural selection factors that affect animal populations can be grouped into density-dependent and density-independent factors. Density-dependent factors include predation, competition, and disease, which tend to have a greater impact on populations as their density increases. Density-independent factors, on the other hand, such as weather, natural disasters, and pollution, affect populations regardless of their density. These factors help regulate population growth and play a vital role in managing populations to prevent extinction or overpopulation.