Can symbiotic relationships change their nature?
Written by
Benjamin Miller
Reviewed by
Prof. Charles Hartman, Ph.D.Symbiotic relationships change between mutualism, commensalism, and parasitism as dynamic responses to environmental conditions. This dynamic change exemplifies the biological adaptability of nature, where partnerships evolve in response to environmental stress. Coral reefs exemplify this dynamic change in change to temperature change. The human microbiomes exhibit the same dynamic changes during shifts in health.
Stress-Induced Shifts
- Heat stress turns coral-algae mutualism into parasitic interaction
- Drought transforms tree-fungi partnerships from mutualistic to parasitic
- Pollution changes bacterial gut relationships from beneficial to harmful
- These shifts occur within days or weeks of environmental changes
Health-Dependent Changes
- Human gut bacteria become harmful during immune system compromise
- Antibiotic treatment turns beneficial microbes into opportunistic pathogens
- Malnutrition triggers commensal organisms to consume host resources
- Medical interventions can reverse these relationship changes
Evolutionary Adaptations
- Species develop new biological responses over generations
- Corals evolve heat-resistant algae partnerships through selection
- Insects build immunity against formerly parasitic fungi
- These adaptations gradually redefine relationship dynamics
Coral reefs show extreme shifts in relationships during warming events. The normally mutualistic algae produce important nutrients for corals through photosynthesis. When water temperatures go above 86 degrees, these algae produce toxins instead. This causes a parasitic relationship or algal bleaching events among corals.
Your microbiome reacts similarly when reflected in patterns of health. In health, good microbes digest food. However, during antibiotic treatment, these same microbes can lead to opportunistic infections. If there is an immune compromise, the normally harmless microbes can become troublesome invaders.
The relationships between fungi and trees change under stress. Mycorrhizal fungi typically exchange soil nutrients for carbohydrates produced by trees. Under drought conditions, these fungi begin feeding directly on tree products. The shift from mutualism to parasitism significantly weakens trees.
Recognizing fluidity among the relationships benefits the ecosystems we wish to conserve. Protecting coral reefs requires us to monitor and/or manage temperature. Supporting the gut microbiome involves avoiding drastic shifts in the bacterial community. Supporting trees for resilience prevents changes in parasitic fungal relationships. Acknowledging these relationships leads to better ecological stewardship.
Read the full article: 10 Symbiotic Relationships Examples in Nature
