In Genesis and Genes, I mentioned Lynn Margulis a number of times. A world-famous biologist, she was elected to the United States National Academy of Sciences in 1983 and inducted into the World Academy of Art and Science, the Russian Academy of Natural Sciences, and the American Academy of Arts and Sciences between 1995 and 1998. She was the recipient of the William Procter Prize for Scientific Achievement (1999) and was awarded the National Medal of Science by President Bill Clinton in that same year. Margulis passed away in November 2011.
Margulis held an unusual position on biological evolution. A fierce critic of the Neo-Darwinian paradigm, she nonetheless subscribed to an evolutionary picture regarding the emergence of the myriad life-forms on Earth today. In April 2011, Margulis was interviewed by Discover Magazine. The entire interview is interesting, but in this post I will focus on a few points that are relevant to material treated in Genesis and Genes and this website.
Readers of Genesis and Genes are aware that Darwin’s Finches are often misleadingly portrayed as paragons of speciation – the process by which one species becomes two. Documenting speciation is vital for evolutionary biology. As I wrote in Genesis and Genes,
Before Darwin, the consensus was that species can vary only within certain limits. Centuries of artificial selection had seemingly demonstrated such limits experimentally. “Darwin had to show that the limits could be broken,” wrote [Evolutionary biologist Keith Stewart] Thomson, “[and] so do we.”
In the interview with Discover Magazine, Margulis is characteristically forthright about Darwin’s Finches.
Discover: What about the famous “beak of the finch” evolutionary studies of the 1970s? Didn’t they vindicate Darwin?
Margulis: Peter and Rosemary Grant, two married evolutionary biologists, said, “To hell with all this theory; we want to get there and look at speciation happening.”…
Discover: Did the Grants document the emergence of a new species?
Margulis: They saw this big shift: the large-beaked birds going extinct, the small-beaked ones spreading all over the island and being selected for the kinds of seeds they eat. They saw lots of variation within a species, changes over time. But they never found any new species – ever. They would say that if they waited long enough they’d find a new species.
In other words, the Grants did not document an instance of speciation; at best, they predicted that it would occur. To this day, there is not a single unequivocal, documented instance of speciation.
This is an exceptionally important point in the context of becoming an informed consumer of science. In the case of speciation, members of the public who express doubt about this process will inevitably be directed to Wikipedia, where numerous instances of speciation are supposedly documented. The Wikipedia sources are arcane and most people will not be able to check the validity of the speciation claim. But ask yourself: if many dozens of iron-clad examples of speciation exist, would a biologist of Margulis’ calibre express scepticism because of Darwin’s Finches? Would Discover Magazine bother to prod Margulis on finch speciation if the issue were settled?
I pointed out in Genesis and Genes that the Grants themselves never claimed to have witnessed speciation. Regarding a particular finch designated 5110 and whose progeny are believed to be the best candidates for demonstrating speciation, a November 2009 report in the journal Nature stated that “the Grants aren’t yet ready to call 5110’s lineage a new species.” Indeed, “the Grants think there is only a small chance that 5110’s descendants will remain isolated long enough to speciate.”
Elsewhere, Margulis made it clear that speciation has not been documented:
Mutations, in summary, tend to induce sickness, death, or deficiencies. No evidence in the vast literature of heredity change shows unambiguous evidence that random mutation itself, even with geographical isolation of populations, leads to speciation.
1. Speciation, a sine qua non for evolutionary biology, has not been observed.
2. Wikipedia is a partisan institution, not to be trusted on questions relating to biological evolution.
I did not discuss the fossil record in Genesis and Genes. Margulis considers it a prime reason to reject Neo-Darwinism.
Discover: What kind of evidence turned you against neo-Darwinism?
Margulis: 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 [currently referred to as the Cambrian Explosion – YB] and then all of a sudden in the fossil record you get nearly all the major types of animals. The palaeontologists 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.
Quite true. What is fascinating is that Margulis points out a powerful critique of Neo-Darwinism that is entirely unoriginal – opponents of evolutionary biology have pointed out for yonks that the fossil record is incompatible with Neo-Darwinism. The difference is that Margulis subscribes to an evolutionary worldview. That makes her sufficiently palatable to be granted an interview by Discover Magazine. If you happen to be a critic of evolution with a different worldview, expect nothing but mockery, regardless of the excellence of your work.
 The interview can be read online:
Retrieved 25th February 2013.
 Keith Stewart Thomson, “Natural Selection and Evolution’s Smoking Gun,” American Scientist 85 (1997): 516-518.
 Daniel Cressey, “Darwin’s finches tracked to reveal evolution in action” Nature, November 16, 2009. The report can be read online:
Retrieved 25th February 2013.
 Lynn Margulis, Acquiring Genomes: The Theory of the Origins of the Species, Basic Books, 2003, page 29.