Scientists
love simple story lines. When they have a simple story line, it
makes it easier for scientists to explain things on television. One
simple story line is the idea that natural selection explains
everything about the origin of mankind. Surely natural selection is a
fundamentally important phenomenon that explains a great deal. But as
I explain here, there are reasons for questioning the story line that
natural selection explains everything about our origins, on the
grounds that there are various refined features of the mind and
spirit that are hard to explain purely through natural selection.
Another
simple story loved by biological scientists is the “DNA stores the
complete blueprint for you” story line. DNA is a molecule stored
in the chromosomes of each of your cells. Each of your cells
contains DNA that consists of about 23,000 different units of
heredity called genes. A gene is a particular combination of
nucleotide pairs in a DNA molecule. The diagram below shows a very
simple gene. Some genes consist of much longer sequences of
nucleotide pairs.
Scientists
also sometimes speak as if we can explain human nature almost
entirely by simply studying the genes in our DNA. We might say that
scientists have enthroned the gene. There never was a formal
coronation ceremony, but the gene was long ago placed on the throne.
In the mind of scientists, it's not King George or King Charles; it's
King Gene. In some cases, scientists have got so infatuated with the
gene, that they have started to personify the gene, speaking in
anthropomorphic terms, almost as if genes were people. An example is
Richard Dawkin's book The Selfish Gene.
But
there are several problems with such thinking. The first is that
scientists haven't been terribly successful in trying to explain all
human characteristics in terms of genes. After a massive effort in
the 1990's, the human genome was decoded. The genome is the complete
set of all genes in the human body. Think of the genome as a big book
listing every gene, and its exact chemical parts. Scientists thought
that decoding the human genome would be some Aladdin's Lamp that
would open the door to thousands of dramatic medical breakthroughs.
But the fruits of decoding the human genome have been relatively
modest. There has been no great river of medical breakthroughs since
the year 2000. How can that be if genes explain almost everything
about us?
Another
curious thing is that when the human genome was decoded, it was found
that the number of human genes was much smaller than expected.
Scientists thought that there might be 100,000 or more human genes,
which seemed reasonable given that there are 17,000 genes in a fruit
fly, 26,000 in a sea urchin, and 38,000 in the simple plant known as
rice. But when the human genome was finally decoded, it was found
that there were only about 23,000 human genes. Given the fact that
humans are vastly more complicated than rice, how is it that we can
have fewer genes, if it is really true that genes store a complete
blueprint for a human?
Another
difficulty is related to the fact that genes are really very simple
things. A gene is just a recipe for making a particular protein in
the body. So how is it that genes can explain even half of the most
advanced characteristics of human beings? For example, humans have
abilities or characteristics such as altruism, philosophical insight,
wonder, spirituality, esthetic appreciation, amazing mathematical
abilities, and an astonishing “built-in” language ability. How
can such things be entirely explained in terms of us having the right
proteins?
The
alphabet used by genes is basically a 4-letter alphabet, which is not
exactly a very rich alphabet for the deepest expression. The 4
letters in a gene's alphabet are A, C, T, and G. It is hard to
imagine some combination of those 4 letters being responsible for
each of the more subtle and refined characteristics of human nature.
Given
these issues, it may be time to consider a rather drastic possibility
– the possibility of dethroning the gene. We could start thinking
along these lines:
Genes
are a very important determinant of human nature. But as they are
merely recipes for making proteins, we cannot at all explain all the
exquisite features of human nature by assuming that the secrets of
human nature are all stored in merely 23,000 genes. There may well be
some completely undiscovered information storehouse that also is
crucial in determining human nature – an unknown noncellular “dark
genome.” When a human body and a full human mind comes into
existence, it may require information from cellular genes and this
mysterious noncellular“dark genome.”
This
would be a bitter pill for scientists to swallow, because they would
have to eat some humble pie. Rather than claiming they have found the
book that explains everything about human nature, they would have to
say: “We have found one important book that helps to explain human
nature, but human nature is also explained by at least one other
important book that we have not yet discovered.”
If
such an undiscovered dark genome exists, where might it exist? We
don't know. It could exist in cells, in some undiscovered part
outside of chromosomes. Or, more likely, it could exist entirely
outside of cells. Such a dark genome might be stored in some larger
cosmic information system. As I explain here, here, and here, there are
strong reasons for believing that there may be some cosmic
information system that has helped to facilitate the universe's
astonishing evolution, its improbable transition from the ultra-hot
density of the Big Bang to its current orderly state. Such an
information system would have three basic required elements:
programming, a database engine, and a computing engine. A tiny
fraction of the data within such a database system may be an
undiscovered dark genome storing instructions on how to make a human
being and a human mind, instructions too complicated to be written in
the simple 4-letter language used by the genes in our cells.
Scientists
studying the universe tried to make everything work without assuming
anything other than known ordinary matter. Eventually they realized
there was no way to do that. So to explain things, they came up with
the vague notions of dark matter and dark energy, the characteristics
of which are unknown. Biologists may eventually have to do something
similar. They may have to conclude that the known genome in our cells
is simply insufficient to explain all of human characteristics,
particularly the subtle and refined abilities of the human mind. Just
as cosmologists were forced to adopt the vague notions of
undiscovered dark energy and undiscovered dark matter, biologists may
have to one day adopt the vague idea that outside of our cells there
is an undiscovered dark genome which stores part of the blueprint for
human beings.
Postscript: Scientists just announced that they had decoded the genome for wheat. According to this news item, "The wheat genome also is more than five times larger than the human genome, the researchers noted." If our genes store the whole blueprint for us humans, how can we have only one fifth as many genes as something as simple as wheat?
Postscript: Scientists just announced that they had decoded the genome for wheat. According to this news item, "The wheat genome also is more than five times larger than the human genome, the researchers noted." If our genes store the whole blueprint for us humans, how can we have only one fifth as many genes as something as simple as wheat?
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