We are fortunate to be living at this very moment in human history,
when we have the power to uncover the information passed from generation
to generation, encoded in our genomes and those of all that is alive.
As chemists, biochemists, engineers and computer scientists and
mathematicians develop even faster, automated methods for analyzing DNA,
it all may seem so technical and aloof from the concerns of most people,
and yet this work not only will transform medical research, but also will
has profound implications for human society.
As we look within our own genomes, what we find resonates with the
teachings of many great religions, that we are all profoundly connected to
each other, and to all life on earth. The information carried within
the genome of any one of us, the order in which the 4 different chemical
letters that make up our DNA are arranged as beads on an approximately 3
billion letters string, is 99.97% the same as that of a perfect stranger.
While we may have been raised in very different environments, from a
multi-million population urban center to a rural setting in an
unindustrialized nation, raised to follow one religion or another, we all
are, profoundly, at our core, so similar to each other.
Each of us has inherited our very similar DNA from 2 parents, 4
grandparents, 8 great-grandparents. If we go back several hundred years,
we will find that we, and others we never met, perhaps you and I, share
many ancestors in common. Our close relationship with all people
extends into the future, as descendants of ourselves and members of our
families meet and marry descendants of others alive today and share in the
creation of new generations of children, and should extend to our hopes to
build together the kind of future in which our shared children can thrive.
Some of the strands in the very DNA molecules within our bodies have come
to us across countless generations, as the two strands of the DNA double
helix separate and are copied, to be passed on as two half-new double
helices every time a cell divides. If we could step back in time to
retrace our DNA¹s path, we will come to some very unexpected ancestors.
We and chimps share a common ancestors, as do, towards the end of the
large dinosaur era, we, chimps and mice. Even further back, we all
share ancestors with plants, and much much further back in time with bread
yeast and even bacteria. All life on earth [except some viruses]
uses DNA as its genetic material, and must copy this same DNA using highly
similar molecular machinery. All life runs its metabolism with
similar chemistry. There are so many molecular similarities within
all life on earth because we are all descended from the same life forms
that evolved these capabilities and passed the information on to its
progeny encoded in DNA. As different families of living things
emerged, they built upon a common framework. Whether a fertilized
egg is from a hummingbird egg or a frog or a human, it must carry
information to make two eyes connected to a brain, four limbs, to digest
food, dispose of waste, and to have a heart beating inside.
It is hard to conceive of how the journey of evolution could have taken
place. Of course, it also is hard to imagine how a single fertilized
egg can, within nine months, develop into a baby with two eyes, four
limbs, eyelashes, and curiosity about the world. We may find it hard to
conceive of evolution, but then we realize that it is hard to conceive of
such long periods of time. In my book Darwin in the Genome, I
propose that just as we learn about the world by living in it, life learns
about adapting to new environments by surviving. Life becomes better
at evolution by survival from generation to generation. While
discussions about Darwin often emphasize ³survival of the fittest,²
calling up images of fierce competitive fighters, in Darwin in the Genome
I emphasize the importance of diversity and cooperation for survival.
Even bacteria cooperate, using a framework that enables them to
share information about antibiotic resistance. Diversity also
is an essential part of fitness. If we were not diverse, we might
all have been wiped out as new pathogens spread rapidly through ancient
communities. As night owls guard the campfire at night, early risers
came to relieve them in the pre-dawn hours. As we look within our
genomes, and those of other living creatures, I expect that we will come
to treasure the diversity of the human species, and indeed, come to
treasure the diversity of all life on earth.
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