Answer:
Some factors that may cause a decrease in population size:
- a high mortality rate due to an infectious disease
- a low birth rate
- a high mortality rate due to interspecific competence
- a high emigration rate
Step-by-step explanation:
In biology, population size (N) refers to the total number of individuals in a given population. The four main factors that affect population size are birthrate (natality), death rate, immigration rate (i.e., the number of individuals of a given species that move into a population), and emigration rate (i.e., the number of individuals of a given species that move out of a population). Both birthrate and immigration are known to increase N, while death rate and emigration are rates known to decrease this value.