organismic selection

biology

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July 19, 2026

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Organismic selection, also known as individual selection, is a fundamental concept in evolutionary biology. It posits that natural selection primarily operates at the level of the individual organism. This means that traits which enhance an individual's survival and reproduction are more likely to be passed on to subsequent generations.1

While the individual is the main unit of selection, debates have occurred regarding other levels, such as group selection or even gene selection. However, the consensus remains that the organism's success in its environment is the direct target of natural selection. This process drives adaptation and the evolution of species over time.123

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philosophy of biology
Levels of selection
In contrast, “organismic selection,” as it may be called, refers to the successes and failures at the level of the organism. Both genic and organismic selection are instances of individual selection, but the former refers to the “replicators”—the carriers of heredity—and the latter to the “vehicles”—the entities…
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In contrast, “organismic selection,” as it may be called, refers to the successes and failures at the level of the organism. Both genic and organismic selection are instances of individual selection, but the former refers to the “replicators”—the carriers of heredity—and the latter to the “vehicles”—the entities…
Read More