struggle for existence

biology

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July 14, 2026

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The "struggle for existence" refers to the automatic competition among members of a natural population for limited resources like food, space, or light. This competition is a fundamental aspect of natural selection, driving evolutionary change.12

In biological communities, competition is a powerful interaction where no species benefits. Species evolve to either avoid each other, tolerate their presence, or aggressively exclude them. This can lead to one species being locally driven to extinction, diverging in resource use, or evolving better competitive abilities. Over time, this competition can result in species filling different ecological niches, as seen in Darwin's finches, where differences in bill size evolved to minimize competition.2

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Darwinism
…to another; and (3) the struggle for existence—which determines the variations that will confer advantages in a given environment, thus altering species through a selective reproductive rate.
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…to another; and (3) the struggle for existence—which determines the variations that will confer advantages in a given environment, thus altering species through a selective reproductive rate.
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philosophy of biology
Evolutionary ethics
…in the natural world the struggle for existence is good, because it leads to the evolution of animals that are better adapted to their environments. From this premise it concludes that in the social world a similar struggle for existence should take place, for similar reasons. Some social Darwinists have…
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…in the natural world the struggle for existence is good, because it leads to the evolution of animals that are better adapted to their environments. From this premise it concludes that in the social world a similar struggle for existence should take place, for similar reasons. Some social Darwinists have…
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survival of the fittest
Use in evolutionary theory
…the fitter, because the “struggle for existence” (a term he took from English economist and demographer Thomas Malthus) is relative and thus not absolute. Instead, the winners with respect to species within ecosystems could become losers with a change of circumstances. For example, fossil evidence supports the notion that…
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…the fitter, because the “struggle for existence” (a term he took from English economist and demographer Thomas Malthus) is relative and thus not absolute. Instead, the winners with respect to species within ecosystems could become losers with a change of circumstances. For example, fossil evidence supports the notion that…
Read More