CLASS 9 · LEARNING KNOWLEDGE

Evolution and natural selection – basic principles

How it works

Evolution describes the change in populations over many generations. Natural selection is a mechanism of evolution: individuals with advantageous, inherited traits survive more often in a particular environment and have more offspring. Variation within a species arises, among other things, through mutation and recombination. As a result, adapted traits can become more common in a population, while less advantageous traits become rarer. Evolution occurs over generations and is often slow, but under strong selection pressure it can also be observed relatively quickly.

Note
Natural selection causes individuals with advantageous, inherited traits to survive and reproduce more often in a particular environment, which spreads these traits through the population.

An example

Why can the proportion of deep roots increase in a dry environment in a plant population with different root depths?

If deeper roots are inherited and provide an advantage in dry environmental conditions, these plants survive more often and produce more offspring. As a result, the trait becomes more common in the population over generations.

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Own explanation and own practice exercises by AmyMath. Subject reference framework: Biology. The topic assignment may vary by federal state.