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Should
Evolution be considered part of Science?
Mukto-mona
Members are responding...
Evolution
and Miracle of Design in the cell
issues
[
Why Evolution is a part of science - An
analysis]
By
T.H.Huxley
In response to : http://groups.yahoo.com/group/mukto-mona/message/6967
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This post was
brought to my attention by Avijit Roy,
one of the personal friends of mine and
the member of another discussion board.
I was invited by him to accept the
challenge of that interesting post on
that site, and I mirror my response
here.
I'll first respond on moderator's
introductory note, after that I'll make
some comments on the Article "The
miracle of design in the cell
written by Mr Yahya (posted by Dr.
Alamgir Hussain). Moderator's note, as
it is posted here, as rhetoric, not as
argument. It consists of three
�questions� (of creationist's) and a
request for three definitions from
evolutionists. I put the word
�questions� in quotation marks
because, as phrased, they are not really
questions at all, but leading statements
which bear little relationship to what
is true. But, I will address them
anyway.
Q1)
So why is evolution given such a lofty
status in science?
Evolution is
given status because it has turned out
to be the central organizing principle
of the biological sciences. There does
not exist a single specialty of
biology that makes sense without it.
It (and ONLY it) effectively explains
taxonomy, genetics, population
genetics, comparative anatomy, botany,
zoology, biostratigraphy,
paleontology, biochemistry,
ecology�. Do you want me to
continue?
Ideas achieve or lose �lofty
status� in science based entirely on
their explanatory power, and their
ability to conform to the facts of
nature better than competing ideas.
Before the idea of evolution was
understood, there really WAS no
�biological science.� There was
simply �natural history.�
Since then, evolution and evolution
based research has turned the
biological sciences into one of the
gems in the crown of human scientific
understanding and achievement.
In short, evolution has achieved its
status as any scientific idea does. It
has earned it because it is better at
explaining the facts than all
competing ideas.
Q2) Should not the theories of
evolution be subjected to the same
stringent tests as with true scientific
theories?
This is not a question; it is actually
a statement (and a false one at that).
It is actually making the claim that
the theories of evolution have NOT
been subjected to the same stringent
tests as other (the writer here
misleadingly calls them �true�)
scientific theories.
Unfortunately for the moderator, as he
put such statement as creationist's
argument, is simply wrong in his
contention. There are no scientific
theories which have been more
thoroughly tested, evaluated, and
�put through the wringer� than the
theories of evolution.
What ARE all those biologists and
paleontologists doing, if not testing
these theories in their work every
single day? What are ALL those
articles in Science, and Nature, and
Paleobiology about anyways, if not
scientists testing these theories? How
were able to reject Lamarck�s
theory, and accept and improve on
Darwin�s theory if we were not
applying the �same stringent
tests� as other theories?
Obviously, one may further confused
(as my friend logical sometimes
appears as well) by the difference
between fact and theory. Theories do
not BECOME facts, theories EXPLAIN
facts. Evolution is both a FACT and
a THEORY.
Darwin gave us a theory (natural
selection) to explain a fact (descent
with modification). It currently
remains (with improvement and
augmentation) the best theory we have
to explain the fact of evolution. It
may be further changed, modified or
replaced, for science is tentative and
progresses.
In the same way, gravity is both a
fact and a theory. Less than a hundred
years ago, we watched one theory of
gravitation (Newton�s) replaced by
another, better theory of gravitation
(Einstein�s), but apples did not
suspend themselves in mid-air awaiting
the outcome of the debate.
Likewise, evolution has occurred and
man has descended from apelike
ancestors (and ultimately reptiles and
fish) whether or not Darwin�s theory
of natural selection ultimately proves
to be THE right theory to explain it.
Q3)
Why is evolution given the privilege
such that even without definite proof,
it is classified as science?
This
�question� rather than making a
claim that is untrue (as in Q2) simply
decides to abandon the understanding
of science altogether. There does not
exist a SINGLE idea in science that
possesses what anyone might call
�definite proof.� Science is
tentative, always open to revision,
always available to be falsified and
improved. Ideas that claim to possess
�definite proof� are not science,
they are dogma.
In reality, evolution and its theories
enjoy no privilege with in science.
They are of a status exactly
equivalent to any other equally
supported scientific ideas,
Finally, the �challenger� presents
three requests for definition. Only
the first two of them are terms of
science, but that�s okay, I�ll
discuss all three.
D1.
Define evolution.
Although it
has several definitions, it is clear
that the author is looking for a
definition relevant to this
discussion, so that is the only one I
will give.
Evolution is the process by which
living organisms are modified over
multiple generations allowing for
speciation and diversification and
resulting (over longer periods) in
dramatic genetic and morphological
change.
Put simply, it is the idea that all
living organisms on the planet earth
have descended from one, or a very few
number of common ancestors.
D2.
Define species.
A species can be defined either
taxonomically or genetically.
Taxonomically, a species is any
population of organisms that share
enough similarity to be included in
the same binomial taxon. Example: our
species is Homo sapiens. Orangutans
are Pongo pygmaeus. Dogs are Canis
familiaris.
Genetically, a species is any
population of organisms than can
interbreed successfully and produce
fertile offspring. For example, horses
and donkeys are DIFFERENT species
because their offspring (mules) are
sterile. Kodiak bears and Grizzly
bears are the SAME species, because
their offspring are fertile. A
species, therefore, is a unit composed
of organisms that can successfully
interbreed. Should a genetic barrier
to reproduction arise between two
populations of what was one species,
then we now have at least one new
species, and we say that
�speciation� has occurred.
3.
Define missing link.
�Missing
link� is not a scientific term. It
is a newspaper term that was
popularized by the commercial media
during the last few years of the
19thtcentury. It was originally coined
to refer to the �missing link�
between humans and apes, and was
regularly applied to fossil findings
that fit the preconceived popular
notions of what such a �link�
might look like. So, Neandertals were
once referred to as �missing
links� (even though they had
actually been found) as was Dubois�
Java Man (Homo erectus), Peking Man
(Homo erectus), Leakey�s
�Zinjanthropus� (Australopithecus
boisei), Darts �Southern Ape Man�
(Australopithecus africanus) and
Johansen�s �Lucy�
(Australopithecus afarensis).
The biggest problem with the term
�missing link� is that it assumes
that evolution works in a linear,
directional way. And it does not. But
popular misconceptions of this type
still find their way into the press
accounts of paleontological
discoveries, as well as into the
rhetoric of creationists.
Now I I'll
make some comments on the Article "The
miracle of design in the cell
written by Mr Yahya. I again thank
Avijt, for sharing this fascinating
example of creationist �gee whiz�
literature. I call it �gee whiz�
because it as a great example of the
stock creationist �argument from
ignorance.� The underlying message is,
�The cell is just SO amazing,
that I can�t imagine how it might have
evolved. And since I can�t imagine it,
it must not have happened.�
I cannot tell you how often I find
myself giving thanks that science and
scientific progress is not limited by
the �imaginations� of some of its
detractors. I am grateful for all the
imaginations better than my own that
have delivered us the modern
technological world in which we live. I
certainly, as a child, could not have
imagined much of what I now encounter
routinely during my day. But I never for
a second would have held MY imagination
up as the standard for what was
possible.
The article, �The miracle of design in
the cell,� depends on the reader
accepting blindly a number of explicit
assertions and some additional
implications that are simply not true.
All else follows from accepting those
initial false premises. So rather than
harp on the silly anthropomorphism that
allows the author to call the cell
membrane �conscious� and �wise,�
I�ll concentrate on exposing the
falsity of the premises on which the
article is based.
The author sets us up by claiming that
�the cell is by far the most complex
structure mankind has ever encountered,
as is also agreed by the scientific
community.� This is so far from the
truth that I had to stop myself from
laughing out loud when I read it. Some
cells are VERY complex, true. Most are
not. But if a cell is complex,
wouldn�t a combination of two or more
cells be at least twice as complex?
I have never heard or read a single
scientist make such a silly claim as
this. I for one would vote for the human
brain as �the most complex structure
mankind has ever encountered,� but
that�s just me. Any representative
sampling of a dozen scientists would
come up with at least three or four
other candidates for the position.
The author extends this claim of
transcendent complexity with his �gee
whiz� trump card. He writes, �In
order for the cell to survive, all the
basic components of the cell, each
performing many vital functions, have to
be intact. If the cell came into
existence by evolution, then millions of
its components had to simultaneously
exist in the same place and they had to
come together in a particular order and
plan.�
It is here that the author stakes his
entire argument, and it is here that his
argument completely falls apart, for
this statement is simply, objectively,
demonstrably not true.
It is clear that cells did not (and did
not NEED to) arise suddenly with all the
current complexity of the most
sophisticated cells already in place and
fully functioning.
They, like all other biological
entities, can be shown to have developed
over time in a stepwise, evolutionary
process.
The fact that there are different kinds
of cells TODAY (some complex, some not)
proves that a cell DOES NOT need all
these components to exist, or to
survive, or even to thrive. The complex
cells of the type discussed by this
author are only the end result of a
lengthy evolutionary history that
included stages when cells did less and
were less complex.
Look (for just one example) at the
difference between Prokaryotes and
Eukaryotes. Prokaryotes are living
cells, and include Monera (simple
bacteria) and Archaea. Simply stated,
prokaryotes are molecules surrounded by
a membrane and cell wall. Prokaryotic
cells lack characteristic eukaryotic
subcellular membrane enclosed
"organelles", but may contain
membrane systems inside a cell wall.
These cells do not need mitochondria, or
golgi apparatus, or ribosomes, or
chloroplasts, or even nuclei. They are
VERY SIMPLE organisms, certainly not
among the �most complex structures
that mankind has ever encountered.�
They lack MOST of the �components�
and are unable to perform MOST of the
�vital functions� that the author
insists a cell requires �in order to
survive.� Yet they survive quite well,
and are arguably the most successful
organisms on the planet. They�ve been
around longer than any other living
thing, they routinely kill and eat us
more complex organisms by the millions,
and while we often talk of an �age of
reptiles� or �age of mammals� the
truth is that we have had only one age
on Earth, and it�s ALWAYS been the age
of bacteria.
The evolutionary pathway from prokaryote
to eukaryote is actually becoming quite
clear. Complex eukaryotic cells appear
to be symbiotic communities of multiple
prokaryotes. Mitochondria (for example)
even have their own DNA, since they were
almost certainly at one time independent
organisms. Chloroplasts in plants appear
to have a similar origin.
But the point here is that it is NOT a
valid argument to take a complex,
eukaryotic cell as an example of a
�starting point� for anything. It is
(I�ll say it again) an end result of
an evolutionary process that had much
simpler cells in its past.
This is where one is compelled to ask
the question as to whether the author
REALLY couldn�t imagine an
evolutionary scenario, or whether they
were simply being disingenuous. For
seriously, how much imagination does it
take to read a text on cell biology and
SEE FIRST HAND (no imagination required)
that there are still living simple cells
that do NOT need to perform all the
�vital functions� this author
insists are necessary?
Of course, at this time the author is
likely to say, �Well, then BACTERIA
are THEMSELVES too complex to have
suddenly arisen with everything in
working order.� To which I would
counter, they DIDN�T �suddenly�
arise either, but also came from less
complex forerunners. Take a virus for
example: We can�t even decide whether
or not they�re actually alive, and all
they consist of is a protein shell and a
piece of genetic material.
His description of the form and function
of a cellular membrane is too "over
the top" to really take seriously.
Ignoring his insistence on conferring
the cell membrane with such attributes
as wisdom, consciousness, memory,
decision making skills, and even (can
you believe it) list keeping, he seems
to have a vision of membrane performance
that is at huge variance with reality.
In fact, he seems to elevate simple
osmosis to a status of artistic
virtuosity that even a Picasso or a
Beethoven would despair of achieving.
Do cell membranes �never allow in more
than what the cell needs?� No, they
OFTEN let in more than what the cell
needs.
Is it true that �there is not a single
unnecessary, purposeless molecule in a
cell?� Of course not. Even most of our
genetic material is �unnecessary and
purposeless,� let alone the random
chemicals and molecules that flood our
systems (and our cells) from a purely
environmental basis.
Does the cell membrane �not permit
even minor errors?� What nonsense is
that? Every cell membrane permits many
errors. Most cells can handle a certain
amount of trauma, uncertainty and
suboptimal performance. And those that
can�t actually do die. All the time.
Every day. By the millions.
It helps no one�s argument to argue
from fantasy, rather than reality. The
author�s constant attitude of �gee
whiz, isn�t that amazing� might be
ameliorated just a little if he had a
more realistic understanding of the
object of his amazement.
I guess in final analysis, the argument
is false because it ASSUMES the act of
creation rather than tries to prove it.
When the author is saying that all these
things had to come together fully formed
at exactly the same time, he�s not
saying that evolution is impossible,
because evolution clearly doesn�t
require that. His posited straw man of
simultaneous, fully functioning, complex
eukaryotes sounds a LOT more like
creation than it does like evolution.
And I would have to agree with the
circular argument that for creation to
have occurred, creation has to have
occurred. But science does not insist of
special creation for living cells, only
this author does.
_________________
T.H.Huxley redux
[ Published at : http://groups.yahoo.com/group/mukto-mona/message/6992
]
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