Saturday, March 7, 2015

The myth of Diversity in a error-prone Environment

The sexual has several parameters at its disposal, in the sense that selection could mold its sexual cycle in any of several different directions (increased fusion, decreased splitting, etc.). We have seen that if damage is low there is a tradeoff between sexuality and asexuality, but that haploids generally beat the diploid due to their superior replication rates. If a sexual uses more fusion than necessary, it relinquishes its superiority to an outcome of competitive coexistence with the diploid (if the haploid is absent). In competition with the haploid, selection might eliminate a "fusion-happy, sexual, perhaps by back-mutation to a haploid in that case.
The asexual haploid cannot cope with high damage. So, when damage is high, only the sexual can compete with a diploid. The sexual cycle must maintain a minimum level of activity before the sexual can even begin to compete with the diploid. If this condition is met, then initial conditions give the outcome to one or the other of the two species or to competitive coexistence. The actual outcome is a function of initial conditions. Our computer experiments have failed to produce interesting dynamical behavior (periodic limit cycles or chaos), and we believe it unlikely that such behavior is possible in this system (for biologically reasonable parameter values) in spite of the large number of free parameters and dimensions. - in Origin of sex for error repair. I. Sex, diploidy, and haploidy.
When Entropy is systematically corrupting Species Complexity, Sexual Selection is the way to go, no other kind of reproduction is able to compete. So, so, simple!

Natural Selection (NS) vs Sexual Selection (SS)

Sexual Selection has nothing to due with Diversity, Natural Selection on Species does. Sexual Selection exists to maintain a strict connection between Species and Organisms, while Species and only Species evolves accordingly with the Environment in a way we call it Natural Selection. So, any Arms Race between forms of life doesn't differs of any other adaptation for what Natural Selection is concerned. The Red Queen Hypothesis is a complication that contradicts the reductionism that many evolutionists like to show off!

New findings show that modern humans, despite having much more population have less diversity that their ancestors. Contrary to the Red Queen Hypnotists, modern humans aren't being afflicted by any wave of parasites... Probably you need a lake of sapience!
"Paleogenomic research has shown that modern humans, Neanderthals, and their most recent common ancestor have displayed less genetic diversity than living great apes. The traditional interpretation that low levels of genetic diversity in modern humans resulted from a relatively recent demographic bottleneck cannot account for similarly low levels of genetic diversity in Middle Pleistocene hominins. A more parsimonious hypothesis proposes that the effective population size of the human lineage has been low for more than 500,000 years, but the mechanism responsible for suppressing genetic diversity in Pleistocene hominin populations without similarly affecting that of their hominoid contemporaries remains unknown. Here we use agent-based simulation to study the effect of culturally mediated migration on neutral genetic diversity in structured populations. We show that, in populations structured by culturally mediated migration, selection can suppress neutral genetic diversity over thousands of generations, even in the absence of bottlenecks or expansions in census population size. In other words, selection could have suppressed the effective population size of Pleistocene hominins for as long as the degree of cultural similarity between regionally differentiated groups played an important role in mediating intraspecific gene flow.
Modern humans display less genetic diversity than great apes, a puzzling finding given our much larger census population size (1, 2). Interestingly, recent studies have shown that modern humans are not the only hominins characterized by comparatively low levels of genetic diversity. The variability of Neanderthal mitochondrial DNA is on par with that found in modern humans (3–5). More importantly, the effective population size of the common ancestor of modern humans and Neanderthals was recently estimated at 9,999 (95% CI: 9,603–10,335)*, concurring with Noonan et al.'s (6) assumption that the effective population size of the common ancestor was similar to that of modern humans, ≈104. Why are all 3 of these Pleistocene hominin populations characterized by levels of genetic diversity that are lower than those found in extant great apes?" - Culture, population structure, and low genetic diversity in Pleistocene hominins
Puzzling? Puzzling is the degree of self delusion in the Scientific Community over the panacea of the Red Queen Hypothesis. No doubts that the modern theory centered only in Natural Selection is akin to a Religion with Genes as its God!

This idea of Diversity, is dismissed not only by the fact that all humans have virtually identical DNA, (Dr David Whitehouse, 2013), but also when no known Human Pandemic as ever ended due to Human Diversity. In the end everything counts but Diversity! Were is that Red Queen that saved us all from the Black Death or the 1918 flu pandemic? The CCR5-Δ32 Gene and its confined success against the Black Plague is the result of Natural Selection and has nothing to due with Diversity. Species was permeated by it, instead of promoting it. But if you think that this proves the necessity of Diversity in the case of a even deadly Virus or Bacteria, just have in mind that reality is not about how things should be, is about how they really are, and Species aren't about Diversity, no matter how much you wish they were! Maybe we only learn in the hard way, and history is a reminder of that...

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