David

“Although random mutations influenced the course of evolution, their influence was mainly by loss, alteration, and refinement... Never, however, did that one mutation make a wing, a fruit, a woody stem, or a claw appear. Mutations, in summary, tend to induce sickness, death, or deficiencies. No evidence in the vast literature of heredity changes shows unambiguous evidence that random mutation itself, even with geographical isolation of populations, leads to speciation.”
― Lynn Margulis, Acquiring Genomes: A Theory Of The Origin Of Species

“Natural selection eliminates and maybe maintains, but it doesn't create... Neo-Darwinists say that new species emerge when mutations occur and modify an organism. I was taught over and over again that the accumulation of random mutations led to evolutionary change [which] led to new species. I believed it until I looked for evidence.”
― Lynn Margulis

“New mutations don't create new species; they create offspring that are impaired.”
― Lynn Margulis

“What kind of grad student do you take? “I never take a straight A student. A real scientist tends to be critical, and somewhere along the line, they had to rebel against their teachers.”
― Lynn Margulis