What about birds?

By: James V. Kohl | Published on: March 14, 2015

A sex researcher who typically fails to respond to my comments and questions recently noted that: “New species are only supposed to arise when a population separates into two.”
She asked: “So what’s going on with the birds on tiny Santa Cruz Island?”
I would have been happy to tell her — if ever she had responded to my past comments. Instead, her question makes good cannon fodder for this blog.
See: This Jay Is Evolving in a Very, Very Weird Way
Excerpt (with my emphasis): “…may not appear to be something you’d consider a “revelation,” but it really is—if you believe in evolution. Ever since Darwin and his famous finches, biologists have thought that in order for a species to diverge into two new species, the two populations had to be physically isolated. Those finches, for instance, each live on a different Galapagos island, where their special circumstances have resulted in specialized bill shapes. Yet the two varieties of island scrub jay (they haven’t technically speciated—yet) live on the same tiny island.”
My comment: I was reminded of a comment made in 1995 by Jay R. Feierman after I presented my detailed model of the gonadotropin releasing hormone-driven pheromone-controlled physiology of reproduction in all vertebrates. He asked: What about birds?  Feierman claims to believe that “Random mutations are the substrates upon which directional natural selection acts.” I suspect that many sex researchers also believe in that pseudoscientific nonsense, which explains why they, too, might ask “What about birds?” If you believe in evolution, you may also believe that they evolved from dinosaurs.
Serious scientists with questions about ecological variation and ecological adaptations in birds would simply refer to our 1996 Hormones and Behavior review article on the RNA-mediated sexual differentiation of cell types. Our model has since been linked via the biophysically constrained chemistry of nutrient-dependent RNA-directed DNA methylation and RNA-mediated amino acid substitutions to the differentiation of all cell types in all individuals of all species.
The answer to the question “What about birds?” has not changed during the past two decades. Social scientists will prefer the comments made by PZ Myers and other biologically uninformed participants on his blog at: One crank dies, another rises to take his place.
Alternatively, on January 16, 2013 I wrote:

“…population geneticists such as Wright (1941) showed that the probability of fixation of these chromosomal rearrangements is so low that they would not be easily established in the population unless population size is very small (say less than 10). For this reason, the idea that new species are formed by chromosomal rearrangements was almost abandoned.”
Almost abandoned? PZ Myers called Davison a “crank” for encouraging discussion of that idea, which has since been fully supported by experimental evidence. Why does an atheistic biology teacher want others to think that someone else is a crank because that person doesn’t agree with the ridiculous idea of mutation-driven evolution?
“The evolution of behavior relies on changes at the level of the genome; yet the ability to attribute a behavioral change to a specific, naturally occurring genetic change is rare in vertebrates. In the white-throated sparrow (Zonotrichia albicollis), a chromosomal polymorphism (ZAL2/2m) is known to segregate with a behavioral phenotype. Individuals with the ZAL2m haplotype engage in more territorial aggression and less parental behavior than individuals without it. These behaviors are thought to be mediated by sensitivity to sex steroids, and the chromosomal rearrangement underlying the polymorphism has captured a prime candidate gene: estrogen receptor 1 (ESR1), which encodes estrogen receptor α (ERα). We therefore hypothesized that the behavioral effects of the ZAL2m rearrangement are mediated by polymorphism in ESR1. We report here that (i) the ESR1 promoter region contains fixed polymorphisms distinguishing the ZAL2m and ZAL2 alleles; (ii); those polymorphisms regulate transcription efficiency in vitro and therefore potentially do the same in vivo (iii); the local expression of ERα in the brain depends strongly on genotype in a free-living population; and (iv) ERα expression in the medial amygdala and medial preoptic area may fully mediate the effects of genotype on territorial aggression and parenting, respectively. Thus, our study provides a rare glimpse of how a chromosomal polymorphism has affected the brain and social behavior in a vertebrate. Our results suggest that in this species, differentiation of ESR1 has played a causal role in the evolution of phenotypes with alternative life-history strategies.”
A few hours later, I was banned from participation. PZ Myers claimed I was a homophobe.
Obviously, he did not want to address the experimental evidence that supported my claims about the role of chromosomal rearrangements. They are nutrient-dependent and pheromone-controlled in all animal species. That fact is a refutation of theories about mutations, natural selection, and the evolution of biodiversity, and it is becoming increasingly more difficult to ignore the biologically-based facts that we detailed in the molecular epigenetics section of our 1996 review.
Excerpt: The Genome, positioning, timings. There are major structural differences between the X and Y chromosomes; e.g., centromeric aiphoid repeats sequences and distribution of heterochromatin (Graves, 1995; Wolfe et al., 1985). These structural differences correlate with sexually dimorphic chromosomal positioning…
Excerpt: Molecular distance. As measured in centimorgans, human and other species’ male and female chromosomes, including the autosomes, tend to have different lengths in various segments. To some extent, this suggests a correlation with physical distance but instead the differing lengths are based upon rates of recombination; although sections of most female chromosomes are longer than their homologous counterparts in male chromosomes, in some segments of various chromosomes opposite length-difference occurs, with males having larger centimorgan values than females in those regions (Lawrence, Collins, Keats, Hulten, and Morton, 1993; Murray, Buetow, Weber, Ludwigsen, Scherpbier-Heddema, Manion, Quillen, Sheffield, Sunden, and Duyk, 1994; Straub, Speer, Luo, Rojas, Overhauser, Ott, and Gilliam, 1993).
Excerpt: Molecular epigenetics. It is now understood that certain genes undergo a process called “genomic or parental imprinting.” Early in embryonic development attached methyl groups become removed from most genes. Several days later, methyl groups are reattached in appropriate sites. Fascinatingly, some such genes reestablish methylation patterns based upon whether the chromosomal segment carrying the gene came from maternal or paternal chromosomes.
All that social scientists and other pseudoscientists can do is ban people like me, who continue to supply accurate representations about biologically-based cause and effect and ask “What about birds?” They really don’t want to know that cell type differentiation is nutrient-dependent and pheromone-controlled in all animal species.  If they did, they would have learned that sometime during the past twenty years — like serious scientists have.
See also:
Insights into the evolution of Darwin’s finches from comparative analysis of the Geospiza magnirostris genome sequence
Evolution of Darwin/’s finches and their beaks revealed by genome sequencing
Every inch a finch: a commentary on Grant (1993) ‘Hybridization of Darwin’s finches on Isla Daphne Major, Galapagos’
Excerpt (with my emphasis): “…ecological speciation and sexual speciation have in this case acted in concert; and in consequence this lineage had proceeded some distance down the path that eventually leads to distinctive ecological specialization and complete sexual isolation [22,34] (figure 6).
My comment: That appears to answer the question about these birds. “So what’s going on with the birds on tiny Santa Cruz Island?” I suspect that ecological speciation and sexual speciation occur via the conserved molecular mechanisms we detailed in 1996 because there is no other model for that. This is the model: Nutrient-dependent/pheromone-controlled adaptive evolution: a model. With few exceptions pseudoscientists and social scientists continue to ignore that fact that this model explains all questions about links between metabolic networks and genetic networks in all species, because the epigenetic links are RNA-direceted by DNA methylation and RNA-mediated amino acid substitutions.
See also: New insights into the hormonal and behavioural correlates of polymorphism in white-throated sparrows, Zonotrichia albicollis

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