Lynn Margulis, an eminent evolutionary biologist, professor at the University of Massachusetts Amherst, and member of the U.S. National Academy of Sciences, has died. She was 73 years old.
Dr. Margulis was well known for advancing the theory of endosymbiosis, which hypothesizes that eukaryotic cells arose when prokaryotic cells engulfed other prokaryotic cells and formed a symbiotic relationship. According to the theory, the engulfed cells ultimately evolved into cellular organelles like mitochondria or chloroplasts found in many eukaryotic cells.
The day that such an eminent scientist dies is a time to remember her and not critique her views, so I will leave a discussion of the flaws and weaknesses in endosymbiosis theory for another day. But Margulis was also a staunch critic of neo-Darwinian theory, and on this day we can affirm many of the things she said about Darwinian biology. In her 2002 book Acquiring Genomes, with Dorian Sagan, she wrote:
We agree that very few potential offspring ever survive to reproduce and that populations do change through time, and that therefore natural selection is of critical importance to the evolutionary process. But this Darwinian claim to explain all of evolution is a popular half-truth whose lack of explicative power is compensated for only by the religious ferocity of its rhetoric. Although random mutations influenced the course of evolution, their influence was mainly by loss, alteration, and refinement. One mutation confers resistance to malaria but also makes happy blood cells into the deficient oxygen carriers of sickle cell anemics. Another converts a gorgeous newborn into a cystic fibrosis patient or a victim of early onset diabetes. One mutation causes a flighty red-eyed fruit fly to fail to take wing. 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 unambigious evidence that random mutation itself, even with geographical isolation of populations, leads to speciation. Then how do new species come into being? How do cauliflowers descend from tiny, wild Mediterranean cabbagelike plants, or pigs from wild boars?”
(Lynn Margulis & Dorion Sagan, Acquiring Genomes: A Theory of the Origins of the Species, p. 29 (Basic Books, 2003).)
In a 2006 article in American Scientist titled “The Phylogenetic Tree Topples,” she similarly wrote that neo-Darwinian biology has failed both to explain the evolution of species, and to correctly understand phylogenetic relationships:
But many biologists claim they know for sure that random mutation (purposeless chance) is the source of inherited variation that generates new species of life and that life evolved in a single-common-trunk, dichotomously branching-phylogenetic-tree pattern! “No!” I say. Then how did one species evolve into another? This profound research question is assiduously undermined by the hegemony who flaunt their “correct” solution. Especially dogmatic are those molecular modelers of the “tree of life” who, ignorant of alternative topologies (such as webs), don’t study ancestors. Victims of a Whiteheadian “fallacy of misplaced concreteness,” they correlate computer code with names given by “authorities” to organisms they never see! Our zealous research, ever faithful to the god who dwells in the details, openly challenges such dogmatic certainty. This is science.
(Lynn Margulis, “The Phylogenetic Tree Topples,” American Scientist, Vol 94 (3) (May-June, 2006).)
In an interview earlier this year with Discover magazine (not affiliated with Discovery Institute) she explained why she rejects the adequacy of mutation and natural selection to account for life’s evolution:
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. Natural selection eliminates and maybe maintains, but it doesn’t create…. [N]eo-Darwinists say that new species emerge when mutations occur and modify and 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.
When asked, “What kind of evidence turned you against neo-Darwinism?” she replies it is a lack of evidence for gradual change in the fossil record:
What you’d like to see is a good case for gradual change from one species to another in the field, in the laboratory, or in the fossil record — and preferably in all three. Darwin’s big mystery was why there was no record at all before a specific point [dated to 542 million years ago by modern researchers], and then all of the sudden in the fossil record you get nearly all the major types of animals. The paleontologists Niles Eldredge and Stephen Jay Gould studied lakes in East Africa and on Caribbean islands looking for Darwin’s gradual change from one species of trilobite or snail to another. What they found was lots of back-and-forth variation in the population and then — whoop — a whole new species. There is no gradualism in the fossil record.
Margulis was no proponent of intelligent design and as far as I’m aware, she was a materialist. But she was a materialist who was critical of the orthodox neo-Darwinian viewpoint, and she took a lot of heat for that. At the very least, for this Dr. Margulis should be admired as a scientist who was courageous enough to say what few others have been willing to say.