What organisms are affected by dead zones in the Gulf of Mexico

Dead zones result from these impacts, which include algal blooms and hypoxia. Phosphorous, nitrogen, and other nutrients increase the productivity or fertility of marine ecosystems. Organisms such as phytoplankton, algae, and seaweeds will grow quickly and excessively on the water's surface.

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not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.