Define natural selection, and describe how natural selection operates as a mechanism of evolutionary change.

Key Concepts

Natural Selection

Natural selection is a fundamental mechanism of evolution, proposed by Charles Darwin. It describes the process by which individuals with advantageous traits are more likely to survive and reproduce, passing those traits to the next generation. Over time, this leads to the adaptation of species to their environments.

Variation and Heritability

For natural selection to occur, there must be variation among individuals in a population, and these variations must be heritable. This means that traits can be passed from parents to offspring. Variations can arise from mutations, genetic recombination, and other processes, providing the raw material for natural selection to act upon.

Survival of the Fittest

The phrase 'survival of the fittest' encapsulates the idea that individuals best suited to their environment are more likely to survive and reproduce. 'Fittest' refers not just to physical strength but to overall adaptability, including behaviors and reproductive success. This concept emphasizes the dynamic nature of populations as they respond to environmental pressures.