What about the famous “beak of the finch” evolutionary studies of the 1970s? Didn’t they vindicate Darwin?
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.’ They measured the eggs, beaks, et cetera, of finches on Daphne Island, a small, hilly former volcano top in Ecuador’s Galápagos, year after year. They found that during floods or other times when there are no big seeds, the birds with big beaks can’t eat. The birds die of starvation and go extinct on that island.
Did the Grants document the emergence of new species?
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.
Some of your criticisms of natural selection sound a lot like those of Michael Behe, one of the most famous proponents of “intelligent design,” and yet you have debated Behe. What is the difference between your views?
The critics, including the creationist critics, are right about their criticism. It’s just that they’ve got nothing to offer but intelligent design or “God did it.” They have no alternatives that are scientific.
You claim that the primary mechanism of evolution is not mutation but symbiogenesis, in which new species emerge through the symbiotic relationship between two or more kinds of organisms. How does that work?
All visible organisms are products of symbiogenesis, without exception. The bacteria are the unit. The way I think about the whole world is that it’s like a pointillist painting. You get far away and it looks like Seurat’s famous painting of people in the park (jpg). Look closely: The points are living bodies—different distributions of bacteria. The living world thrived long before the origin of nucleated organisms [the eukaryotic cells, which have genetic material enclosed in well-defined membranes]. There were no animals, no plants, no fungi. It was an all-bacterial world—bacteria that have become very good at finding specialized niches. Symbiogenesis recognizes that every visible life-form is a combination or community of bacteria.
How could communities of bacteria have formed completely new, more complex levels of life?
Symbiogenesis recognizes that the mitochondria [the energy
factories] in animal, plant, and fungal cells came from oxygen-respiring bacteria and that chloroplasts in plants and algae—which perform photosynthesis—came from cyanobacteria. These used to be called blue-green algae, and they produce the oxygen that all animals breathe.
Are you saying that a free-living bacterium became part of the cell of another organism? How could that have happened?
At some point an amoeba ate a bacterium but could not digest it. The bacterium produced oxygen or made vitamins, providing a survival advantage to both itself and the amoeba. Eventually the bacteria inside the amoeba became the mitochondria. The green dots you see in the cells of plants originated as cyanobacteria. This has been proved without a doubt.
And that kind of partnership drives major evolutionary change?
The point is that evolution goes in big jumps. That idea has been called macromutation, and I was denigrated in 1967 at Harvard for mentioning it. “You believe in macromutation? You believe in acquired characteristics?” the important professor Keith Porter asked me with a sneer. No, I believe in acquired genomes.
Can you give an example of symbiogenesis in action?
Look at this cover of Plant Physiology [a major journal in the field]. The animal is a juvenile slug. It has no photosynthesis ancestry. Then it feeds on algae and takes in chloroplasts. This photo is taken two weeks later. Same animal. The slug is completely green. It took in algae chloroplasts, and it became completely photosynthetic and lies out in the sun. At the end of September, these slugs turn red and yellow and look like dead leaves. When they lay eggs, those eggs contain the gene for photosynthesis inside. Or look at a cow. It is a 40-gallon fermentation tank on four legs. It cannot digest grass and needs a whole mess of symbiotic organisms in its overgrown esophagus to digest it. The difference between cows and related species like bison or musk ox should be traced, in part, to the different symbionts they maintain.
But if these symbiotic partnerships are so stable, how can they also drive evolutionary change?
Symbiosis is an ecological phenomenon where one kind of organism lives in physical contact with another. Long-term symbiosis leads to new intracellular structures, new organs and organ systems, and new species as one being incorporates another being that is already good at something else. This major mode of evolutionary innovation has been ignored by the so-called evolutionary biologists. They think they own evolution, but they’re basically anthropocentric zoologists. They’re playing the game while missing four out of five of the cards. The five are bacteria, protoctists, fungi, animals, and plants, and they’re playing with just animals—a fifth of the deck. The evolutionary biologists believe the evolutionary pattern is a tree. It’s not. The evolutionary pattern is a web—the branches fuse, like when algae and slugs come together and stay together.
In contrast, the symbiotic view of evolution has a long lineage in Russia, right?
From the very beginning the Russians said natural selection was a process of elimination and could not produce all the diversity we see. They understood that symbiogenesis was a major source of innovation, and they rejected Darwin. If the English-speaking world owns natural selection, the Russians own symbiogenesis. In 1924, this man Boris Mikhaylovich Kozo-Polyansky wrote a book called Symbiogenesis: A New Principle of Evolution, in which he reconciled Darwin’s natural selection as the eliminator and symbiogenesis as the innovator. Kozo-Polyansky looked at cilia—the wavy hairs that some microbes use to move—and said it is not beyond the realm of possibility that cilia, the tails of sperm cells, came from “flagellated cytodes,” by which he clearly meant swimming bacteria.
Has that idea ever been verified?
The sense organs of vertebrates have modified cilia: The rods and cone cells of the eye have cilia, and the balance organ in the inner ear is lined with sensory cilia. You tilt your head to one side and little calcium carbonate stones in your inner ear hit the cilia. This has been known since shortly after electron microscopy came in 1963. Sensory cilia did not come from random mutations. They came by acquiring a whole genome of a symbiotic bacterium that could already sense light or motion. Specifically, I think it was a spirochete [a corkscrew-shaped bacterium] that became the cilium.
Don’t spirochetes cause syphilis?
Yes, and Lyme disease. There are many kinds of spirochetes, and if I’m right, some of them are ancestors to the cilia in our cells. Spirochete bacteria are already optimized for sensitivity to motion, light, and chemicals. All eukaryotic cells have an internal transport system. If I’m right, the whole system—called the cytoskeletal system—came from the incorporation of ancestral spirochetes. Mitosis, or cell division, is a kind of internal motility system that came from these free-living, symbiotic, swimming bacteria. Here [she shows a video] we compare isolated swimming sperm tails to free-swimming spirochetes. Is that clear enough?
And yet these ideas are not generally accepted. Why?
Do you want to believe that your sperm tails come from some spirochetes? Most men, most evolutionary biologists, don’t. When they understand what I’m saying, they don’t like it.
We usually think of bacteria as strictly harmful. You disagree?
We couldn’t live without them. They maintain our ecological physiology. There are vitamins in bacteria that you could not live without. The movement of your gas and feces would never take place without bacteria. There are hundreds of ways your body wouldn’t work without bacteria. Between your toes is a jungle; under your arms is a jungle. There are bacteria in your mouth, lots of spirochetes, and other bacteria in your intestines. We take for granted their influence. Bacteria are our ancestors. One of my students years ago cut himself deeply with glass and accidentally inoculated himself with at least 10 million spirochetes. We were all scared but nothing happened. He didn’t even have an allergic reaction. This tells you that unless these microbes have a history with people, they’re harmless.