Lynn Margulis rocked the biological world with her 1967 declaration that mitochondria were actually embedded bacteria somehow absorbed several hundreds of millions of years ago by animal life. The formidable Ernst Mayr declared her contribution "of enormous importance."
Margulis rejects the current trends of mathematical microbiology and neo-Darwinism. Her belief is that "evolution" occurs not by natural selection, but by sudden stresses forcing symbiogenesis. This is not exactly the same as Stephen Jay Gould's punctuated evolution, but goes toward solving the same issue.
Essentially, organism living in close proximity comingle and absorb microorganisms that in turn give them benefits that make sudden leaps forward for them to overcome the environmental stress, and to dominate their niche in that same environment. Examples are mitochondria in animals and chloroplasts in plants. Therefore evolution explodes in big jumps, not gradual selection over aeons.
She offers a specific example of a slug that ingested algae absorbing the chloroplasts making the slug photosynthetic. It also changes colors to reds and yellows exactly as leaves do when seasons change. In her view, cows are 40 gallon fermentation tanks. People hear because at some point a cilia containing bacteria was absorbed into the ear canal mechanism that was super-sensitive to calcium crystals (balance/vertigo) and sound waves. Also the cones in the eye.
Therefore, life does not branch, it forms webs of intersections at given times and environments. And we are in a real sense a complex web of millions of types of microorganisms in symbiosis all harmonized and specifically selected to our environment to attack and repel other microorganisms that are not acceptable to the conglomerate.
Margulis thus proposes one of the most radical forms of materialism in biology. We are unique only because of our incorporated microorganisms long ago disguised as organs and tissue. It is the collective "consciousness" of quadrillions of micro-life-forms that make us both individuals and species. Any radical alteration of these collectives then make us – or any other collective-organism - very different species or life-forms. It also explains a lot of parallel evolution. Like micro-environments or macro-environments create collectivisms that mimic one another (emus, ostriches, rheas, etc.)
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And this news flash may flow right into Margulis' mincrobe-materialist viewpoint of evolution.
Experts at Edinburgh University set out to discover how the Transylvanian naked neck chicken (the Churkey) came by its appearance. A protein influenced by production of Vitamin A, BMP12, is produced, suppressing feather growth and causing the bird to have a bald neck. The findings could help poultry production in hot countries because chickens with naked necks were better equipped to withstand the heat. They also have implications for understanding how birds, including vultures, evolved to have featherless necks. Transylvanian naked neck chickens are thought to have originated from the north of Romania.
Kansas: Dust in the Wind.
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