Friday, 9 May 2014

“Natural Selection Eliminates … But It Doesn't Create,” The Evidence Says

One of the most famous examples of natural selection: slight variations in beak sizes in Darwin’s finches. Image courtesy of John Gould, via Wikipedia.

Joel Kontinen

While the late evolutionary biologist Lynn Margulis accepted evolution, she became increasingly doubtful of the power of Darwinian mechanisms, i.e. natural selection and random mutations.

Dr. Margulis said that neo-Darwinian thinking was problematic. In an interview published in Discover Magazine she stated:

This is the issue I have with neo-Darwinists: They teach that what is generating novelty is the accumulation of random mutations in DNA, in a direction set by natural selection. If you want bigger eggs, you keep selecting the hens that are laying the biggest eggs, and you get bigger and bigger eggs. But you also get hens with defective feathers and wobbly legs.”

Many dog breeds have all kinds of ailments and weaknesses for a similar reason, so this is not a problem that only concerns hens. She went on to say:

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 -- led to new species. I believed it until I looked for evidence.”

Many scientists, it seems, believe in a theory that lacks evidence. One might perhaps ask whether it deserves being called a theory.


Discover Interview: Lynn Margulis Says She's Not Controversial, She's Right. Discover Magazine, p. 68 (April, 2011).