The term for the critical mutualistic interactions between species is symbiosis. This biological phenomenon occurs when two species engage in a close, often long-term relationship that benefits at least one of the parties involved. There are different types of symbiosis, including mutualism, where both species benefit, and commensalism and parasitism, where one organism benefits while the other is unaffected or harmed. Symbiotic relationships are essential for ecosystem stability, enhancing nutrient cycling, and providing resilience against environmental changes. Understanding these interactions can inform conservation and ecosystem management strategies.