Why is it that two species cannot occupy the same niche for an extended period of time?

Answer 1

Two species cannot occupy the same niche for an extended period of time because they will be competing for the same resources, such as food, water, and shelter. As they try to outcompete each other for these resources, one species may eventually become dominant, while the other may either move to a new habitat or go extinct. This competition for resources can also lead to changes in the physical or behavioral characteristics of the competing species as they adapt to the demands of their environment, which can further reduce their ability to coexist. Ultimately, natural selection favors the species that is better adapted to its niche, and this eventually leads to the displacement of the less adapted species.