Final answer:
Some populations are inherently cyclical due to seasonal changes in resource availability and the vulnerability of small populations to stochastic events.
Step-by-step explanation:
Some populations are inherently cyclical due to seasonal changes in resource availability. Fluctuations in the environment, such as variation in rainfall and food sources, can affect birth and death rates in populations. For example, in a population of herbivores, the availability of food during the rainy season may lead to an increase in population size, while scarcity of food during the dry season may result in a decrease in population size.
In addition, small isolated populations are particularly vulnerable to catastrophic events like floods, fires, droughts, or hurricanes. These events can greatly reduce the population size or even cause local extinctions.
So, the cyclical nature of these populations can be attributed to the impact of changing environmental conditions and the vulnerability of small populations to stochastic events.