Five Types of Ecological Relationships | Sciencing
Some have lifelong relationships with other organisms, called symbiotic relationships. There are three different types of symbiotic relationships: mutualism. Ecological relationships describe the interactions between and among organisms within their environment. These interactions may have. Antagonism: Antagonism, in ecology, an association between organisms in which one are able to efficiently extract energy and nutrients from their environment.
Spirilla and vibrios in marine environments, prostecate bacteria in oligotrophic lakes 5.
Its stability depends on the interactions or interrelationships amongst populations and the adaptaion of these populations to the environment as seen in the figure above. Gastrointestinal GI tract of new born is sterile. The final stable community forms, "climax" community. Flavobacterium disappear in 8 days and lactobacilli in 18 days.
Lactobacillus is the pioneer, which leads to succession by facultative anaerobes E. Climax communities include cellulose decomposers Bacteroides, Ruminococcusprotein degraders Veillonellastarch degraders Selenomonasand methane producers Methanobacterium. Interactions within a single microbial population Positive interactions cooperation: Low density means loss exceeds replacement.
May lead to problems in isolating pure cultures. Pathogenicity associated with "minimum infectious dose" MID.
Ecological Synergies – Complexity Labs
A single cell rarely overcomes host defenses. In nature, microcolonies rather than individual cells are observed. An inhibitor is less effective on a dense culture rather than a sparse culture. Transformation, transduction conjugation occurs more efficiently at high densities than at low densities genetic exchange of antibiotic ressistance genes, heavy metal ressistance genes, genes which provide ability to utilize unusual organic sustrates.
Negtive Interaction competition High densities can lead to accumulation of toxic products. The Double Negative Competition exists when multiple organisms vie for the same, limiting resource.
Because the use of a limited resource by one species decreases availability to the other, competition lowers the fitness of both. Competition can be interspecific, between different species, or intraspecific, between individuals of the same species. In the s, Russian ecologist Georgy Gause proposed that two species competing for the same limiting resource cannot coexist in the same place at the same time.
As a consequence, one species may be driven to extinction, or evolution reduces the competition. Sciencing Video Vault Mutualism: Everyone Wins Mutualism describes an interaction that benefits both species. A well-known example exists in the mutualistic relationship between alga and fungus that form lichens.Exploring Ecosystems: Coral Reef Symbiosis - California Academy of Sciences
The photsynthesizing alga supplies the fungus with nutrients, and gains protection in return. The relationship also allows lichen to colonize habitats inhospitable to either organism alone. In rare case, mutualistic partners cheat. Some bees and birds receive food rewards without providing pollination services in exchange. These "nectar robbers" chew a hole at the base of the flower and miss contact with the reproductive structures. As an example, cattle egrets and brown-headed cowbirds forage in close association with cattle and horses, feeding on insects flushed by the movement of the livestock.