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Darwin the Genius of Evolution
Warren Hochfeld
When Charles Darwin published his groundbreaking theory of natural selection
in 1859, it was received by the public with considerable discontent. His
theories were introduced in his landmark publication, The Origin of Species in
which he hypothesised that positive heritable traits would make it more likely
for an organism to survive long enough to reproduce over successive generations:
over time population adaptations that specialize organisms for a particular
habitat or situation may eventually result in the emergence of a stronger
organism, this process was termed natural selection. This year marks the 200th
birthday of Charles Darwin and the 150th anniversary of The Theory of Evolution.
Widely accepted by scientists as the blueprint for the engine of life, his work
remains one of the strongest influences on modern society sculpting our
understanding of what it means to be human. It was quite simply the best idea
anyone ever had…
Modern scientific breakthroughs mostly confirm Darwin’s theories, providing
an explanation for the physical basis of variation underlying evolution:
Mendel’s genetics and the discovery of the structure of DNA provide the apparent
explanation of the origin and inheritance of human characteristics. The
fundamental element of this explanation is a functional unit called the gene,
each of which govern, or assist in governing, the incredibly diverse array of
traits within a species. Genes are composed of strands of a molecule called DNA
and are located within chromosomes. The genetic message is encoded by the
building blocks of DNA, which are called nucleotides. Each person's genetic
makeup is a result of his/her unique sequence of nucleotides. The expression of
these genes result in the production of proteins, which serve as building blocks
for tissues as well as the regulators of chemical reactions taking place inside
all living cells. They control everything from the colour of our eyes, the
texture of our hair, the amount of oxygen one carries in their blood and many
other factors.
However as our general understanding of genetic mechanisms advances, so does our
ability to manipulate them. Western society has been saturated with therapeutic
treatments, and with the encouragement of the medical establishment itself has
started to look beyond therapeutic interventions. Conceptually, if you consider
the world only at the molecular level, genetic manipulation is a logical,
straightforward solution to genetic disease: if a gene seems to be causing a
disease, then to cure the disease scientists must remove the “defective” gene,
and substitute it with the “effective” gene. In an ideal scenario, the cell with
the corrected DNA will multiply, producing more copies of the corrected gene
thus freeing the body of the genetic abnormality and curing the disease. As
ordinary medicine can only moderate symptoms of genetic diseases and treatments
are typically only temporary, genetic manipulation has the potential to
eliminate the root causes of certain diseases by repairing or modifying the
patient’s genetic code.
Advocates for genetic medicine are convinced that controlling our
evolutionary destiny is humankind's next great social frontier. There argument
stems from personal health, individual choice, and a collective responsibility
for future generations. The cornerstone concept is that everyone has the right
to be "well-born” and genetic manipulation will lead to a perceived improvement
of the human gene and the betterment of society as a whole. The foremost
practitioner is Nobel laureate James Watson, the co-discoverer of DNA, who is an
outspoken proponent of using genetic engineering to "redesign" future children
and "improve" the human species. During the recent "DNA at 50" celebrations,
Watson stated that, “The right to a custom-made child is merely the natural
extension of our current discourse of reproductive rights.”
While natural selection favours "Survival of the fittest" evolutionary
biologists have questioned whether this will actually lead to the best possible
organisms in the long run. Parents in the biotech century will be increasingly
forced to decide whether to take their chances with the traditional genetic
lottery and use their own unaltered egg and sperm, or undergo corrective gene
changes to their sperm, egg, embryo, or foetus. Of course one could choose to go
with the conventional approach and let genetic fate determine their child's
biological destiny, but is it not a parent’s responsibility to provide as safe
and secure an environment as is humanly possible for their unborn child? Knowing
their children may inherit some "undesirable" traits, is it not a parent's
failure to correct genetic defects in utero, something they could have avoided
had they made use of corrective genetic intervention at the sex cell or embryo
stage.
2009 has been named The Year of Darwin, as universities, academic centres,
and other scientific organizations all over the globe have a surplus of events
planned to honour his contributions. But we can’t help but wonder what Darwin
would think if he could survey the state of his intellectual achievement today,
200 years after his birth.
Darwin did not write about genetic engineering or even about genes as he
lived before their time. Nevertheless, genetic engineering is a form of human
selection that began before anyone even spoke of genes. Darwin did state this
when comparing human selection with natural selection: “Man selects for his own
good: Nature only for that of the being which she tends.” Darwin’s perspective
was that human selection was not only anthropocentric, it was foolish. Darwin
was a naturalist and believed that the wiser path for humanity was to leave
selection to nature, because species and varieties of species selected by the
long, slow process of nature, “should be infinitely better adapted to the most
complex conditions of life, and should plainly bear the stamp of far higher
workmanship.”
The years in which human selection has been practiced are miniscule when
compared by geological time and the billions of years over which natural
selection produced its species. It seems incongruent to believe that natural
selection explains the origin of the species and to believe that human selection
holds the hope for our future. Darwin was probably as right about our future as
he was about our past.
* Warren Hochfeld has a BCom from Unisa, an MSc from The University of
Pretoria, and is currently engaged in PhD research at The Department of Medical
Genetics, Cambridge University.
See Nelson Mandela Science lecture
on Darwin.
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