Essay On Trade Offs

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Trade-offs Trade-offs often occur when the members of a system are competing with each other. It is one of the most prevailing acknowledgements for coexistence in the communities. The ‘Darwinian demon’ theory indicated that “Trade-offs between survival and reproduction, however, constraints any organism from realistically resembling that creature.” Similarly, ‘Hutchinson demon’ theory also pinpointed whereby “one species in a community dominates because it is best colonizing new patches, utilizing all the resources, avoiding predators and resisting stresses.” Trade-offs in a community can be controlled by several limiting factors, such as scarce of resources, abiotic factors like pH, salinity, presence of sunlight, and presence of competitors. Interspecific trade-offs are typically thought to be a requirement for species coexistence in communities at small spatial scales. Within meta-community context, trade-offs are still often harbingered as imperative for coexistence at a regional scale rather than local scale. There are three elements of trade-offs among competing species within a trophic level like the interaction between local and regional trade-offs, regional-scale coexistence and trade-offs and species diversity at multiple spatial scales (alpha, beta, gamma). When environments are diversified and irregular, species can exhibit trade-offs in their ability to utilize local habitats and to exploit patches regionally. When the dispersal rates are low, each species persists only in the habitat type in which they are favored; local diversity is low. In contrary, at the highest rates of dispersal, species that are better at colonizing empty patches can dominate and drive other species extinct, even though those species ... ... middle of paper ... ...ches and different species are favored under different environments. As dimensionality increased control of community dynamics was predicted to shift from local to regional processes. Species can coexist at the local and regional scale by specializing on a specific habitat. Specialists, by definition, have highest fitness in a particular habitat and the trade-off is then exhibited across habitat types, whereas generalists do not exhibit trade-offs across habitat types. Coexistence at local scale will occur between habitat generalists and specialists, while regional scale coexistence will occur between difference habitat specialists and generalists. Increasing connectedness among patches may decrease beta diversity and increase alpha diversity in certain situations; dispersal rates essentially shift the relative importance of local and regional scale trade-offs.

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