Use an example from nature to explain how natural selection causes populations to change as their environment change include the following terms variation trait genes

Galapagos finches have various beak sizes that make foraging for food more successful.

Explanation:

Organisms evolve over time due to changes in their genome. These are pontaneous, and occur in DNA at random. These changes are called mutations and form alleles or different forms of a gene.

Over time within a population, the number alleles increase the variation of the population. These variants may confer specific traits within an individual, that may confer a biological advantage.

Thus, the trait may make the organisms more capable of obtaining food, shelter a mate etc. or ensure survival, i.e. they are able to pass on their genes to the next generation.