Note that this change was not due to pollution making the moths darker. The dark variety had always existed in small numbers, but only had a selective advantage when the selection pressure changed.

For example, if heterozygotes at a locus have higher fitness than homozygotes (a scenario known as heterozygote advantage or overdominance), natural selection will maintain multiple alleles at ...

The phrase "survival of the fittest" functions principally in evolutionary theory to describe the biological concept of natural selection ... through Principles of Biology when Darwin was working ...

Students could look at examples of plants like the commonly ... reveals the ways in which plant breeders can speed up natural selection. Biology KS3 / KS4: How the combine harvester has changed ...