Final answer:
The concept that no two species can occupy the same ecological niche in the same place and time is called the competitive exclusion principle.
Step-by-step explanation:
The concept that states that no two species can occupy the same ecological niche in the same place and the same time is the competitive exclusion principle. This principle states that if two species were to occupy the same niche, they would compete with one another for the same resources in the environment. Eventually, one species may outcompete and replace the other, or they may evolve different adaptations to reduce competition and continue to coexist.