Question

as a mechanism of evolution, natural selection acts on variants within populations and ultimately leads to different species. this was proposed by multiple choice lyell. mendel. darwin. founder malthus.

Explanation:

Charles Darwin (along with Alfred Russel Wallace) is credited with proposing the theory of evolution by natural selection, which states that natural selection acts on heritable variations in populations, driving evolutionary change and the formation of new species. Lyell was a geologist, Mendel studied genetics, "Founder" refers to a genetic drift effect, and Malthus wrote about population growth that influenced Darwin but did not propose natural selection as an evolutionary mechanism.

Answer:

Darwin.