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Biological evolution is a fact that is demonstrated by an abundance of evidence too voluminous to list. Theories concerning mechanisms of biological evolution, which have moved beyond the Darwinism that creationists attack in strawman arguments, are empirically supported explanations for the operation of biological evolution.
"God did it by performing miracles" is no explanation at all, though it seems adequate for those with an inculcated, emotional insistence that they are God's special creations. Such people, in failing to employ critical thinking, cannot reasonably claim to be the product of 'intelligent design' because they demonstrate an emotion-distorted failure of understanding.
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Mechanisms of Biological Evolution
However, morphologic changes may reflect alterations in the regulation of genetic expression without a major alteration in genotype – witness the considerable differences that selective breeding has wrought in size and configuration within one canine species. Similarly, the paramount importance of gene regulation probably explains much of the morphological difference between humans and chimps – two species who share 98% of their DNA. Recently, researchers have demonstrated that gene regulation has enabled rapid phenotypic speciation in sticklebacks. Along the same lines of modification of genetic expression, alternative splicing enables a single gene to give rise to multiple versions of a protein.
mutation → allele → pre-mRNA → constitutive pre-mRNA splicing and/or epigenetic alternative splicing → proteins → intergenerational fate of allele
There are two basic types of mechanism involved in biological evolution. First are the genetic sources of alteration of a gene within the genotype of an individual. Second are those statistical mechanisms that determine the fate of an altered allele. These are the mechanisms that increase or decrease frequency of an allele (a form of a gene at a locus) within a population.
?► Mechanisms and Evolution : Darwinism :
Expressed Atheism
The numbers of people identifying themselves as atheists in surveys have been a small fraction of the population, and atheist organisations have had relatively little impact on the wider cultural landscape. But this could be changing. The high public profile (and sales) of recent books by Dawkins, Richard Dennett, AC Grayling, Sam Harris and Christopher Hitchens suggests growing numbers of people may be being drawn to identifying themselves in opposition to religion. Dawkins’s declared interest in making atheism more publicly acceptable - exemplified by the sale of ‘A for atheism’ T-shirts on his website - demonstrates that this phenomenon is not simply about philosophical debates concerning the existence of God. The sheer ferocity of many of the atheist critiques of religion also suggests that we are not in the territory of reasoned debate, but witnessing the birth pangs of a new, anti-religious cultural identity. We are now seeing a concerted effort being made to validate an atheist cultural identity through media and consumer products, just as evangelicals have already used these resources to consolidate their form of Christian identity in the modern world.
Describing atheistic responses as “sheer ferocity” sounds rather hysterical! Dawkins is currently vilified as some sort of antichrist figurehead.
Hitherto, we atheists/Atheists have probably been more polite about our nonacceptance of the religious dogma with which society is inundated. We either do not believe in God (small a) or are certain that no deity exists (capital A), yet we do not usually set out to attack religion.
Professionl Religionists, as distinct from mild-mannered believers, have previously enjoyed tax-protected status for their promotion of arrogant claims of knowing the “Truth” and for their assumption of the high moral ground. I suspect that much of the anti-religious backlash also reflects antagonism aroused by illogical attacks on scientific knowledge perpetrated in attempts to preserve the illusion of creationism.
I have recently been engaged in debate with an anti-Dawkins, pro-ID, religious apologist who peppers his (perhaps her, though I doubt it) arguments with selected quotes from writers and philosophers. Interesting though the discussion has been, I am utterly unconvinced by any line of argument that relies upon selected quotes of previously (sometimes 2000+ years earlier) expressed ideas. One can use an idea to clarify an idea, but it is not good intellectual practice to attempt to justify concepts solely on the basis of other conceptualizations — an infinite regress of ideas that effectively clarifies nothing. It strikes me that this form of fuzzy, emotional thinking is typical of religionists.
People having had, and continuing to have, a variety of passionately expressed opinions counts for nothing in comparison to the actual import of those ideas. It strikes me that this is the chief difference between philosophers and scientists. Philosophy is not without value, nor does it offer nothing to our understanding of the world, but it is inherently self-limited in so far as philosophy manipulates language about language about language and so risks becoming divorced from reality. Navel gazing, in practice and effect.
Modern philosophers of science acknowledge that science has supplanted the old metaphysical formulations about the world, yet the pro-ID debater seems blissfully unaware of this and insists on quoting medieval philosophers on metaphysics. Modern philosophers of religion admit that attempts to prove the existence of God have all failed, yet creationists persist in illogical attempts to discredit science.
Science — which those of philosophical bent like to diminish in import with labels such as Logical Positivism – formulates concepts about the physical world on the basis of physical realities. It is extraordinary that thousands of years of human attempts to understand the physical world neglected the obvious — that we can only understand the physical by examining the physical. Darwin is the usual target of anti-evolution bandwagons despite the fact that modern evolutionary biology has moved far beyond his theory of natural selection. Anti-Darwinian propaganda may be motivated by the fact that Darwin gave the religious community a real scare. However, this focus is more likely explained by the fact that Darwinian concepts are simple enough that the religiously motivated can explain them to other creationists and that they provide an opportunity for straw man attacks on evolutionary theory. Further, natural selection is so well established as a mechanism for biological evolution that this concept is taught in high school biology and few creationists seem to have more knowledge of science.
Creationists seem not to understand not only the content of science, but also the actual nature of science. Creationists fear science because at some level that they will not admit they know that science supplants God as they understand “Him”. As a result they either deny scientific facts, invent pseudoscience, or attack scientists.
Finally, does any of this matter? To those of us who identify with liberal and progressive cultural movements, whether religious or humanist, there are potentially worrying trends here. The intensity with which new atheist identities are being forged through a hatred of imagined religious others is matched by the hatred felt by some conservative religious groups towards those they perceive as godless."new atheist identities . . . forged through a hatred of imagined religious others” . . . strong language to describe a long overdue reaction to the concerted misinformation campaigns that religious fundamentalists have employed against knowledge.
Lynch attempts to explain the upsurge of atheist expression as being, “in part, as a reaction to the perceived threat of Islam.”
If the upsurge of atheism were partly or mostly a reaction to Islamic threats, reaction would surely take the form of pro-Christian, anti-Islamic statements and would not focus on promoting evolutionary theories or decrying the rigid dogmatism of Christian fundamentalism (now called evangelicism) or lamenting past Christian atrocities directed against any difference of opinion.
No, Mr. Lynch, the upsurge of expressed atheism is really pitted against moralistic ignorance and is pro-truth. The upsurge of expressed atheism is a reaction to the attempt to further undermine education by forcing religion into science classrooms. The upsurge of expressed atheism is a reaction to the funding and propaganda poured into promoting whatever variant of religionist dogma.
Darwinism
Charles Darwin accurately predicted that his theories would evoke skepticism from scientists and ridicule from the religious. Happily, scientists came to accept his ideas, and his breakthrough insights have proved highly influential. Unhappily, those biblical literalists who insist that "Genesis" is an accurate description of life's origins, continue to unjustly vilify Darwin's theories.
Summary of Darwin's observations and his Theory of Evolution by Natural Selection:
1. Most animals have such high fertility rates that their population size would increase exponentially if all individuals were to reproduce.
2. Yet, except for seasonal fluctuations, populations remain relatively stable in size.
3. Because environmental resources are limited, individuals compete for resources, limiting survival and reproduction.
4. Individual characteristics vary within populations and those members of a population that are better adapted for survival in the face of competition are more likely to pass their characteristics on to the next generation.
5. Thus, species gradually accumulate inherited adaptations that best suit them for their environment, passing these on to progeny. Speciation involves gradually accumulated differentiation of characteristics.
Darwin was not aware of the existence of DNA, nor of the mechanisms that alter genotype. Darwin focussed on the inheritance of adaptive individual characteristics that had ensured reproductive success, and the resultant slow accumulation of adaptive phenotypic change. Darwin did not say that all species are gradually evolving (cf. quote.)
Subsequent evolutionary theorists first disputed Darwin's concept of gradual evolution. Gould and Eldredge introduced the concept "phyletic gradualism " which they discredited through the concept of punctuated equilibria. The Theory of Punctuated Equilibria was proposed in order to explain patchiness in the fossil record and the the localized adaptive radiation of species observed following extinction events. This stage of thinking about evolutionary mechanisms has been termed "Neo Darwinism".
Modern advances in molecular genetics, coupled with studies of population genetics have led to the "Modern Synthesis" of understanding concerning mechanisms of evolution. Current understanding incorporates knowledge of genetic drift, gene flow, mutation, recombination, and natural selection mechanisms.
Creationists and defenders of "intelligent design" theory commonly attack a "strawman" depiction of Darwinism or Neo-Darwinism as representing current thinking in their attempt to discredit evolutionary science. It is important for any person wishing to defend evolution-as-fact and modern evolutionary theories to attain a thorough understanding of modern evolutionary theory as well as fallacious creationist arguments.
