Now one could say, at the risk of some superficiality, that
there exist principally two types of scientists. The ones, and they are rare,
wish to understand the world, to know nature; the others, much more frequent,
wish to explain it. The first are searching for truth, often with the knowledge
that they will not attain it; the second strive for plausibility, for the
achievement of an intellectually consistent, and hence successful, view of the
world. To the ones, nature reveals itself in lyrical intensity, to the others
in logical clarity, and they are the masters of the world.
Erwin Chargaff, Preface to a Grammar of Biology (1971)
An important
corollary of Natural Design is that modern evolutionary theory is lacking in
key regards, contrary to the widespread belief that our understanding of
evolution is now complete in all but its finest details. This is not the case;
Darwin himself had no idea how complex and multifaceted the matter was and key parts
of his theory, long admired and cherished for their elegant simplicity and
indisputable truth, have over time evolved and undergone adaptation. For
instance, the role of natural selection—the most fundamental aspect of Darwin’s
theory—is being revisited and its status as evolution’s primary driver called
into question. (It is now accepted belief that several factors are at work,
each of which is subject to selective pressures.) As well, by the time Darwin’s
ideas had gained widespread acceptance, no one had yet given serious thought to
the evolution of physiological processes and systems. Complex biomolecules such
as DNA, unknown at the time, also have evolutionary histories. Natural Design
offers a new angle on such matters.
Before
tackling these convoluted topics, a historical overview of how modern
evolutionary theory took shape will provide useful perspective. This will be
followed by a look into scientific
materialism—a stance based on the assumption that all phenomena are solely
the result of physical (“material”) matter being acted on by natural laws,
nothing more—and how this approach became the basis for all scientific
methodology. Again, this is pertinent to the Natural Design viewpoint.
The
two bedrock assumptions that Darwin’s theory of evolution by natural selection
is founded on are that there can be random variations in genetic material (mutations)
which can lead to adaptations that in
turn might improve an organism’s chances of survival. The late paleontologist and
evolutionary biologist Stephen Jay Gould, summarizing its main tenets: “First,
that all organisms produce more offspring than can possibly survive; second,
that all organisms within a species vary, one from the other; third, that at
least some of this variation is inherited by offspring. From these three facts,
we infer the principal of natural selection: since only some of the offspring
can survive, on average the survivors will be those variants that, by good
fortune, are better adapted to changing local environments. Since these
offspring will inherit the favorable variations of their parents, organisms of
the next generation will, on average, become better adapted to local
conditions.”
During
the two decades Charles Darwin spent working out his ground-breaking theory,
neither he nor any of his peers had any idea how unimaginably complex the
manifold workings of life actually were. As an illustration of how little was
understood it that era: German biologist Ernst Haeckel, a contemporary and
great admirer of Darwin’s, believed that the cell (still a little-known entity)
was “not composed of any organs at all, but consist[ed] entirely of shapeless,
simple, homogeneous matter…nothing more than a shapeless, mobile, little lump
of mucus or slime….”
While
Darwin was slowly and meticulously refining his ideas following the voyage of
the Beagle, a congenial and
self-effacing Austrian friar was growing pea plants in his abbey’s garden. Over
the course of eight years, Gregor Mendel patiently reared almost 30,000 plants
while piecing together the foundation of modern genetics.[1
Due
to a number of adverse historical circumstances, Mendel’s far-reaching insights
went unrecognized for nearly half a century. Significantly, after all his
painstaking labor and meticulous recording of data, the priest’s findings were
made known solely through two public lectures followed by a paper submitted to
the Proceedings of the Natural Science
Society of Brünn. Aside from that one
obscure 1866 publication, Mendel personally distributed 40 reprints of the
treatise to suitable people and…his seminal research quickly all but
disappeared. It was ignored by fellow botanists, who found themselves confused
about the object of it all. They perceived the work as being merely about
hybridization (animal breeding and horticulture being a feature of their
day-to-day lives), and were put off by Mendel’s perplexing reliance on numbers.
While this might seem odd today, scientifically rigorous experimentation
involving statistics was a foreign concept to biologists of that era.
Mendel’s
efforts were largely forgotten until 1900, when three European plant
physiologists, independently performing similar experiments, simultaneously
brought to light the friar’s enormous contribution to science. Mendel’s
treatise Experiments with Plant Hybrids had
been published seven years after the first edition of On the Origin of Species came out but, despite an apocryphal story that Darwin owned a copy but never read it, there is no evidence
he was aware of the work.[2]
(Many scholars believe that Darwin, whose mathematical skills were poor, in all
likelihood would not have recognized its implications.) Mendel, long in poor
health, died at only sixty-one. All his papers, all his scrupulous
documentation, were carted out to a hill behind the abbey shortly after his
death and unceremoniously burned.[3]
Once
brought to light, Mendel’s ideas rapidly gained traction. Early geneticists
debated a growing number of conflicts with Darwinian precepts. These were based
in part on the realization that Mendel’s laws had shown that inheritence was a
material affair that could be tested by experiment, not the result of Darwin’s
more abstract and somewhat nebulous selective process. Many believed that
traits were inherited in the form of discrete units, which could be accounted
for by the newly discovered phenomenon of mutation (rather than a measured
blending as called for by natural selection).
The
discovery of genes as “particulate” units of inheritance had a huge effect on
accelerating evolutionary research. In the 1920s and 30s, following the
acceptance of chromosome theory, a
new discipline emerged: population
genetics (the study, heavy on statistical analysis, of how traits arise and
move through populations). Thanks largely to work by two Britons—statistician
Ronald Fischer and biologist J.B.S. Haldane—and American geneticist Sewall
Wright, Mendelian genetics and the concept of evolution by natural selection
were finally integrated: a unification that became feasible only after it was
finally recognized that the gradual, steady modification central to Darwin’s theory
was entirely compatible with Mendel’s axioms. This paved a way to resolve
various disputes that had been intensifying for some time.
These
conflicts were for the most part put to rest during the course of an
international symposium held at Princeton in 1947, shortly after WW II’s travel
restrictions had lifted. It became known as the modern Darwinian synthesis. The
synthesis was basically a set of ideas that were assertively championed by bird
taxonomist-cum-evolutionary biologist Ernst Mayr and several of his chief
collaborators in America, notably paleontologist George Gaylord Simpson,
expatriate Soviet geneticist Theodosius
Dobzhansky, and botanist G. Ledyard Stebbins—all prominent experts in their
fields. In England, well-known biologist and science popularizer Julian Huxley
(grandson of Thomas, “Darwin’s bulldog) used his public visibility to spread
the word, in particular in promoting his vision of human progress through
evolution.
Up
until that time, researchers working in disciplines such as paleontology, systematics, and natural history were
neither in close communication nor sharing their findings. To some extent,
these areas were all influenced by Darwinian theory (even though many of his
ideas had long since fallen out of favor). The specific disciplines’ views on
evolutionary agencies and their relative importance had diverged; each was
starting to attribute different meanings to established concepts and use
different terminology to describe them. Some had even formed their own evolutionary
theories. Population-level thinking had not yet taken hold. Of even greater
concern, paleontologists were actually at odds with the concept of natural
selection—a consequence of not seeing the gradual changes required by its
precepts reflected in their established fossil records. Those working with
population genetics were convinced they had finally found a way to connect the
different disciplines.
The symposium, considered a
great success, united many branches of biology under one common evolutionary umbrella
that (according to Gould) “validated natural selection as a powerful causative
agent and raised it from a former status as one of a contender among many to a
central position among mechanisms of change.” This had been the gathering’s
intended goal. Mayr made clear that the intention of the synthesis was no less than a means to “designate the general acceptance of two
conclusions: gradual evolution can be explained in terms of small genetic
changes (‘mutations’) and recombination, and the ordering of this genetic
variation by natural selection; and the observed evolutionary phenomena,
particularly macroevolutionary processes and speciation, can be explained in a
manner that is consistent with known genetic mechanisms.”
The true significance and
influence of natural selection was still being debated until Dobzhansky
reaffirmed its primacy with the publication of his book Genetics and the Origin of Species in 1937—a critical, solidifying
event in the movement’s early development.[4]
The alliance thereafter commonly became known as “the synthesis” (although, in
time it became known—somewhat erroneously—as neo-Darwinism.[5])
However, like Darwin and his contemporaries, Mayr and his esteemed colleagues had little notion of the real complexities
lying beneath the surface of their various disciplines. Microbiology was in its
infancy and the helical structure of DNA was yet to be revealed. No botanists
ecologists, or embryologists had attended the symposium and new findings in
those fields and others would muddy the water for years to come.
Due in part to the strong
personalities and fervor of neo-Darwinism’s promoters, from its outset the
movement was infused with a zealousness that made it notably resistant to
change—an ironic misfortune, since all the scientific branches concerned were
in flux. By the 1950s the movement started to move away from the pluralism of
the 1930s and 40s in favor of an almost complete emphasis on adaptationism (the view that many traits
are the result of evolution through natural selection). The synthesis entered a
phase of intellectual rigidity—what Gould later christened “the hardening.”
What had set out as a collaborative integration began to exclude and
marginalize.
The following decades
witnessed a flood of new information and ideas, some of which received a great
deal of resistance. Only fifty years later, leading experts became increasingly
aware that the modern synthesis was in serious need of modernization. While it
has taken time, it is now becoming widely recognized that evolutionary theory
is a considerably less straightforward matter than was previously assumed, with
problematic questions still surfacing. For one thing, we now know that natural
selection is but one of a number of influences driving the whole process. Also,
during this same period there has been a parallel broadening of perspective
with regard to the evolutionary aspects of all branches of biology. Thanks to
the arcane strangeness of quantum theory, a growing understanding of the microscopic
realm, and the newly revealed universe of the cell, we have arrived at a more
sophisticated appreciation of nature’s subtleties and complexities. The entire
framework of the way we view life has
shifted. But it remains a work in progress.
©2017 Tim Forsell 19 Nov 2017
[1] Properly speaking, Mendel was from Moravia, a historic region in what is now the
Czech Republic. Many misconceptions surround Mendel and his work: for one, he
was a friar—not a monk—and lived not at
a monastery but at an abbey, among a
community of very talented and learned men. (Moravia, in the early 1800s, was
ahead of its time in promoting the power of science in order to improve social
and economic conditions and was a region known for its advanced animal breeding
and horticulture.) Another thing: it was a happy coincidence that Mendel chose
to work with pea plants. He had no way of knowing that the traits he chose to
follow were controlled by genes found on different chromosomes and those traits
also happened to denote distinct, unambiguous features not typically displayed
in such regular fashion.
[2] Mendel and his peers were well-acquainted with
Darwin’s work. (Mendel had a
well-worn copy of Origin.)
[3] The complicated story of the simultaneous “rediscovery”
of Mendel’s research is somewhat out of the scope of this work but quite intriguing.
Mendel’s obscure publication had been passed around by a few plant breeders.
Among those who had read the paper were Dutchman Hugo de Vries, German Carl
Correns, and Austrian Erich von Tschermak. Working independently, each achieved
in their own experiments results similar to Mendel’s. Correns barely missed out
on beating de Vries to publication and there is evidence that both intended to
claim discovery of what became known as Mendel’s
Law (the 3:1 ratio of dominant versus recessive characteristics generated
by the hybridization of two purebred strains). Coincidently, de Vries sent
Correns a copy of his newly published article, written for a French journal,
that made no mention of Mendel. Correns was just then putting the last touches
on his own manuscript and, bitter at having been upstaged, hurriedly finished
his own paper and sent it to the German Botanical Society for publication.
Correns made a point of crediting Mendel with the 3:1 law’s discovery to
undercut de Vries’ claim to priority; whether or not he intended to do the same
is still debated. But, unbeknownst to
Correns, de Vries had already sent his
paper to the German Botanical Society and, in this version, had credited
Mendel. Thus was Mendel’s work rediscovered and handed over to science.
[4] Dobzhansky was the first geneticist to work in the
field with natural populations. He “helped to establish population genetics as
the empirical field that provided the long-missing piece to the original
Darwinian puzzle.”
[5] George Romanes, a protégé of Darwin’s, “coined the
term neo-Darwinism to refer to the
version of evolution advocated by Alfred Russell Wallace and August Weismann
with its heavy dependence on natural selection…[rejecting] the Lamarckian idea
of inheritance of acquired characteristics” (a commonly held notion of the era
that Darwin himself had embraced).
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