05. Phylogeny
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Phylogeny Darwin deserves credit for the theory of natural selection, but the concept of phylogeny is the null hypothesis and thus a no-brainer. As observed in an earlier essay, phylogeny is the correct presumption regardless of the mechanism used to explain it. If natural selection is an unsatisfactory explanation, then let phylogeny be explained by something else. If creationists have issues with Darwin, then let them criticize Hennig and Kauffman. Darwin’s cardinal insight was the recognition of recursive environmental feedback. As cited in a previous essay, Daniel Dennett notes in Darwin’s Dangerous Idea that Paley asserted that the observed order in nature required intelligent design. Darwin then demonstrated that consciousness is not necessary for an intelligent design process. Adaptation can emerge and accumulate even without the help of foresight. There exists a creationist t-shirt that reads, “By Design and Not By Chance,” as if this were controversial. Actually, and apparently unbeknownst to creationists, there is no significant Darwinian dispute about this. In accordance with the second law of thermodynamics, species spontaneously decay into fragments incapable of mutual genetic communication. The resulting reproductively isolated sibling species are free to adapt independently. The resulting adaptations will be natural reactions to natural forces, like falling downhill, or the mutual forces of attraction and repulsion of magnetic poles. However, they will not necessarily be the best possible solutions under the circumstances because, as noted in a previous essay, complex systems are easily trapped in suboptimal modes (see Waldrop). Adaptation relies heavily on plagiarism and recruitment, such that the wheel need not always be reinvented. In the lineage immediately ancestral to birds, feathers are thought to have arisen prior to the emergence of flight as integumentary appendages derived from keratinocytes, and were initially selected for “insulation, water repellency, courtship, camouflage and defense” according to Richard O. Prum and Alan H. Brush (Scientific American, March 2003). They were later exapted for flight. Cryptochromes are light-sensitive proteins that could have been recruited in the early evolution of the eye. Noting that the skull seems to be derived from teeth, Neil Shubin, in Your Inner Fish, observes that 500 million years ago, ostracoderms had a bony head plate “made up of thousands of small teeth fused together.” Adaptation can be most easily accomplished via the loss of an existing trait, yielding evolutionarily derived simplification. Webbed digits are easily achieved via failed apoptosis (programmed cell death) during development, which would normally separate digits. In an example of neoteny, the adult human skull resembles that of a juvenile ape, humans having lost the alveolar prognathism characteristic of adult apes. Vicariance biogeography exploits the dynamic geology of plate tectonics to help explain allopatry. Populations can become separated involuntarily if the ground moves beneath them. Thus the fragmentation of biological species can be facilitated by parallel geological phenomena. This writer has found the following sources to be useful: Brooks, D.R. and E.O. Wiley. Evolution as Entropy: Toward a Unified Theory of Biology. The University of Chicago Press, 1986. ISBN 0-226-07581-8. 1 of 128 Kauffman, Stuart A.. The Origins of Order: Self-Organization and Selection in Evolution. Oxford Uni. Press, 1993. ISBN 0-19-507951-5. Weber, B.H., D.J. Depew, and J.D. Smith, eds. Entropy, Information, and Evolution: New Perspectives on Physical and Biological Evolution. The MIT Press, 1988. ISBN 0-262- 23132-8. Wiley, E.O.. Phylogenetics: The Theory and Practice of Phylogenetic Systematics. John Wiley & Sons, 1981. ISBN 0-471-05975-7. Creationism Creationism is a denial of phylogeny, even though any exception made to common descent weakens an explanation relative to a strictly phylogenetic one. Consider a cladogram with the origin for a certain character at its base. The dendriticity of the cladograms allows distribution of a character to descendant via inheritance. This allows for basal (and therefore quantitatively minimal) character origins. Synapomorphy, then, is the property that allows allows cladograms to be optimized such that they represent the least falsified genealogy, and that allows phylogenetic theories to falsify typical creation theories. Nondendritic creationist models cannot accommodate this logical simplification because a negative heuristic protects core assumptions from modification and improvement (mole ruit sua). To accommodate creationism, all the nodes of a cladogram must be erased, forcing a basal character origin to divide and climb up the tree in advance of this erasure until the character has been incorporated into all the terminal branches, becoming redundant autapomorphies. The result is not even an unresolved polychotomy. Quantitatively, all diagnostics, such as consistency index and F-ratio, characterize the phylogenetic perspective as vastly more parsimonious (facile princeps). Qualitatively, esoteric speculation are similarly better done without. Thus creationism is fatally hobbled by ideological constraints, resulting in the victory of phylogeny being a horizon job (jucundi acti labores). As Ricky Roma says in Glengarry Glen Ross, “[Expletive deleted]. You owe me the car.” This is the fundamental pitfall of all creationist arguments in nuce. A creationist bumper sticker reads: “There’s no monkey in my family tree.” If so, then said tree has less explanatory utility and is less parsimonious than that offered by science, making the latter better. Therefore, science wins and its dust may be freely eaten. Or, as they say at the University of Southern California, “Palmam qui meruit ferat.” Ontogeny and phylogeny (or, if one prefers, development and evolution) respectively involve the differentiation of cells and species. Organisms ontogenetically develop, while species phylogenetically evolve. Creationists somehow manage to deny phylogeny but not ontogeny. They amusingly do not believe that all terrestrial organisms evolved from a common organismal ancestor over a period of several billion years, yet they somehow manage to believe that they themselves were recently unicellular, their bodies having developed from a single common cellular ancestor in just decades. Pastor Michael Jones has said, “I could never believe we come from goo.” He is obviously speaking phylogenetically, though he almost certainly believes it ontogenetically. Ken Ham of Answers in Genesis says of a picture of a chimpanzee, “Did your grandmother look like this?” and also employs a graphic depicting an embryo labeled “Domestic cat” that bears no resemblance to an adult cat. If Ham does not believe that humans and chimps share a common ancestor that lived millions of years ago, then how cam he allow himself to 2 of 128 believe that an adult cat could develop from something that it does not resemble? Ironically, creationists acknowledge that they themselves once not only looked like but actually were zygotes. So, why not disbelieve intraspecific genealogy? Let DNA tests not be accepted for paternity if they are not accepted for phylogeny. There are said to be weaknesses in evolutionary theory, which is inevitably and trivially true of all theory and thus an accent fallacy. Darwinian theory is said to have “gaps,” and yet biology survives them, being no more endangered by them than by the “gaps” in Newtonian physics. Creationists call evolution a “questionable” assertion, as if to question were to impugn, which it is not, as interrogatives lack truth value. All synthetic propositions are necessarily contingent and all history is necessarily conjectural. But some conjectures yield better explanations than others. And, by definition, the supernatural is the inscrutable realm from which answers are unavailable. So, in addition to being questionable, natural explanations, unlike their supernatural rivals, are answerable. This is the Radio Shack Principle: questions are no problem for those who have answers, especially the best ones. Let all question, but let no one misanswer. As noted previously, some creationists claim that evolutionary theories leave them unmoved, though movement is not a valid evaluative criterion, and creationists should not be forgiven for thinking that it is. Nor is apathy a virtue in itself. There are many people, according to one commentator, for whom space exploration “has no meaning or value,” though it may be confidently assumed to have just as little meaning to just as many dogs. The value of science is not based on an argumentum ad populum, nor is scientific truth subject to focus groups. “Of all lies, art is the least untrue,” observes Gustave Flaubert. Science, though it employs explanatory fictions, is not a lie because, unlike much religion, it acknowledges its fictitious aspects. A distinction is to be made between fiction that is scientifically enabling and that which is merely emotionally enabling but otherwise destitute of explanatory utility. Though creationism may be of some historical interest and may be a potent self-esteem generator among the blissfully unaware, it is nonetheless a theory of the most extraordinary scientific inconsequence. The null hypothesis is not a claim that a drug, for example, is not effective, only that the alternative hypothesis bears the burden of proof. Failure to recognize this is the argumentum ad ignorantiam. In the absence of testability,