Final answer:
True, stochastic processes, which are random events like natural disasters or genetic drift, do contribute to an extinction event. These processes can significantly affect small and isolated populations, potentially leading to their extinction when combined with human impacts.
Step-by-step explanation:
True, processes of chance do contribute to an extinction event. When populations become small and isolated, they are particularly susceptible to a number of stochastic processes, which are essentially random events that may pose little threat to larger populations. These random events can include natural disasters, genetic drift due to random mutations, and other chance occurrences that can have a profound impact on small populations leading to their extinction.
For example, impacts by comets and asteroids are chance events that can cause mass extinction events. Additionally, the selective disappearance of certain genotypes as a result of random natural disasters, such as a storm killing all white rabbits in a population, represents genetic drift, which is a stochastic process that can lead to changes in a population's genetic structure and potentially contribute to extinction.
Moreover, experiments have shown that extinction events can be influenced by conditions of environmental variability, inbreeding depression, and chaotic and oscillatory behavior in populations, all of which may have stochastic elements. Thus, rarity caused by small range size or local scarcity does not itself cause extinction; rather, it is the collision of human impacts with these susceptibilities that can lead to extinction events.