Symbiosis is a close and long-term biological interaction between two or more different species. These organisms, called symbionts, live together in a relationship that can be beneficial, neutral, or harmful to one or both parties involved
. There are several types of symbiotic relationships:
- Mutualism : Both species benefit from the interaction. For example, gut microbes help humans digest food while receiving nutrients and habitat in return
- Commensalism : One species benefits while the other is neither helped nor harmed.
- Parasitism : One species benefits at the expense of the other, which is harmed
Symbiosis can be:
- Obligate : The organisms depend on each other for survival.
- Facultative : The organisms can live independently but choose to associate
Symbiotic relationships occur in many environments, including terrestrial and marine ecosystems, and involve a wide range of organisms such as microbes, plants, and animals. Examples include corals hosting algae, deep-sea fish partnering with bioluminescent microbes, and bacteria living inside animals at hydrothermal vents
. In summary, symbiosis is about "living together" and encompasses a spectrum of interactions from mutually beneficial to harmful, shaping ecological and evolutionary dynamics among species.
