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HOME > PAST ISSUE > May-June 2006 > Article Detail

FROM THE PRESIDENT

The Phylogenetic Tree Topples

What is "evolution?" If evolutionary theory (like the law of gravity or the periodic table of chemical elements) stems from accepted scientific knowledge, why is its teaching controversial? We seek here the source of the controversy: where evidence ends and dogma begins. No honest, rigorous and logical scientist appreciative of hard-earned data from nature disagrees about evolution's incontrovertible core. Then why are so many who celebrate science as a most, if not the most, effective way of knowing about the world confused by lack of scientific unanimity? None doubts that gravity is the force that accelerates falling bodies, nor are statistics required to predict gas behavior when oxygen and hydrogen are sparked in a closed volume!

Why isn't everyone convinced that "evolution is a fact, not just a theory" when biologists feel evolution of life from past life is as well established as gravity or the explosive chemical reaction of H2 and O2 to form water? Professionals in geology, biology and especially biochemistry concur: Evolutionary phenomena proffer crucial organizing principles. So what's the problem? Evolutionary biologists act certain that they know how new life forms originate and complexify. But they don't.

Evolution, no single fact, depends on four observable processes. First, life requires the incessant flow of energy and matter to survive. Second, a species-specific biotic potential, a measurable quantity, is assignable: the number of offspring that, in principle, can be produced per generation. A human couple has 20 children maximum. A single E. coli bacterial cell that doubles in 20 minutes potentially reaches a population size the weight of the Earth in less than a week! Third, all populations grow at rates more rapid than their immediate environment sustains. What Darwin called natural selection is simply this fact of elimination: Never do 100 percent of the offspring survive to reproduce 100 percent. Finally, offspring are not identical to their parent(s); observable inherited (genetic) change is easily measured.

From these facts Darwin correctly inferred that life "descended with modification" from common ancestors. Overwhelming evidence for this fact (and none against) comes from, e.g., animal behavior, biochemistry, comparative anatomy, ecology, genetics, geochronology, microbiology, physiology, paleobotany, sedimentary geology, virology and zoology, amplifying Darwin's insight. More than 30 million kinds of life, placed unambiguously into five huge groups—bacteria, protoctists (including 50 phyla of ciliates, diatoms, red and brown seaweeds, slime molds, water molds), fungi, animals and plants—evolved during the past 3,500 million years from our small common ancestors: bacteria. Study of long-chain molecules such as chitin, DNA, lignin, protein, yields spectacular evidence for the shared ancestry of all living matter. Watery cell metabolism (chemical transformation by salt balance, synthesis of proteins and other metabolites  always bounded by cell membranes) is incessant whether in aardvark or zoogloea.

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.


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