Final answer:
Intraspecific and interspecific competition both lead to a decline in population densities due to lower reproductive rates, increased mortality, and reduced access to resources.
Step-by-step explanation:
When a population encounters both intra- and interspecific competition, there is a more significant decline in population densities. Intraspecific competition occurs when individuals of the same species compete for limited resources, such as food, water, and mates. Interspecific competition happens when individuals of different species compete for the same limited resources. Both types of competition lead to a decrease in population densities because they result in lower reproductive rates, increased mortality, and reduced access to resources.
Learn more about Competition in population