Re: [asa] Scientists urge evolution lessons

At 03:12 PM 6/21/2006, Jack Haas wrote:
>Janice,
>
>"..I'll put off your question [ What does hard
>science (biological evolution) have to do with
>the *origin* of life on earth? ] a bit longer before
>responding. After all, What does a retired
>physical chemist know? ~ Jack Haas

At 07:59 PM 6/21/2006, Don Nield wrote:
>Janice Matchett wrote:
>
>>In a veiled attack on creationism, the world's
>>foremost academies of science on Wednesday
>>*called on parents and teachers to provide
>>children with the facts about evolution and the origins of life on Earth. .."

>>I note that Janice has replaced "origins" with
>>"origin". The hard science (biological
>>evolution) rules out some views on origins (e.
>>g. separate creation of "kinds").
>~ Don

@ Jack wasn't distracted by my typo.
Nevertheless - neither of you get "the point". That's the sad part.

I'll take any 10 people off the street --- or any
10 scientists off the street, and I'll guarantee
you that if you ask them to give you their
opinion as to the "origins of life on earth", the
majority will assume you're asking them a
theological - not a biological - question.

"..[biological] evolution is simply a process
that results in heritable changes in a population
spread over many generations."

~ Janice

What is Evolution?
Copyright © 1993-1997 by Laurence Moran

Most non-scientists seem to be quite confused
about precise definitions of biological
evolution. Such confusion is due in large part to
the inability of scientists to communicate
effectively to the general public and also to
confusion among scientists themselves about how
to define such an important term.

When discussing evolution it is important to
distinguish between the existence of evolution
and various theories about the mechanism of
evolution. And when referring to the existence of
evolution it is important to have a clear
definition in mind. What exactly do biologists
mean when they say that they have observed
evolution or that humans and chimps have evolved from a common ancestor?

One of the most respected evolutionary biologists
has defined biological evolution as follows:

"In the broadest sense, evolution is merely
change, and so is all-pervasive; galaxies,
languages, and political systems all evolve.
Biological evolution ... is change in the
properties of populations of organisms that
transcend the lifetime of a single individual.
The ontogeny of an individual is not considered
evolution; individual organisms do not evolve.
The changes in populations that are considered
evolutionary are those that are inheritable via
the genetic material from one generation to the
next. Biological evolution may be slight or
substantial; it embraces everything from slight
changes in the proportion of different alleles
within a population (such as those determining
blood types) to the successive alterations that
led from the earliest protoorganism to snails,
bees, giraffes, and dandelions." - Douglas J.
Futuyma in Evolutionary Biology, Sinauer Associates 1986

It is important to note that biological evolution
refers to populations and not to individuals and
that the changes must be passed on to the next
generation. In practice this means that,
Evolution is a process that results in heritable
changes in a population spread over many generations.

This is a good working scientific definition of
evolution; one that can be used to distinguish
between evolution and similar changes that are
not evolution. Another common short definition of
evolution can be found in many textbooks:

"In fact, evolution can be precisely defined as
any change in the frequency of alleles within a
gene pool from one generation to the next." -
Helena Curtis and N. Sue Barnes, Biology, 5th ed. 1989 Worth Publishers, p.974

One can quibble about the accuracy of such a
definition (and we have often quibbled on these
newsgroups) but it also conveys the essence of what evolution really is.

When biologists say that they have observed
evolution, they mean that they have detected a
change in the frequency of genes in a population.
(Often the genetic change is inferred from
phenotypic changes that are heritable.) When
biologists say that humans and chimps have
evolved from a common ancestor they mean that
there have been successive heritable changes in
the two separated populations since they became isolated.

Unfortunately the common definitions of evolution
outside of the scientific community are
different. For example, in the Oxford Concise
Science Dictionary we find the following definition:

"evolution: The gradual process by which the
present diversity of plant and animal life arose
from the earliest and most primitive organisms,
which is believed to have been continuing for the past 3000 million years."

This is inexcusable for a dictionary of science.

Not only does this definition exclude
prokaryotes, protozoa, and fungi, but it
specifically includes a term "gradual process"
which should not be part of the definition. More
importantly the definition seems to refer more to
the history of evolution than to evolution
itself. Using this definition it is possible to
debate whether evolution is still occurring, but
the definition provides no easy way of
distinguishing evolution from other processes.
For example, is the increase in height among
Caucasians over the past several hundred years an
example of evolution? Are the color changes in
the peppered moth population examples of
evolution? This is not a scientific definition.

Standard dictionaries are even worse.

"evolution: ...the doctrine according to which
higher forms of life have gradually arisen out of lower.." - Chambers

"evolution: ...the development of a species,
organism, or organ from its original or primitive
state to its present or specialized state; phylogeny or ontogeny" - Webster's

These definitions are simply wrong.

Unfortunately it is common for non-scientists to
enter into a discussion about evolution with such a definition in mind.

This often leads to fruitless debate since the
experts are thinking about evolution from a different perspective.

When someone claims that they don't believe in
evolution they cannot be referring to an
acceptable scientific definition of evolution
because that would be denying something which is
easy to demonstrate. It would be like saying that
they don't believe in gravity!

Recently I read a statement from a creationist
who claimed that scientists are being dishonest
when they talk about evolution. This person
believed that evolution was being misrepresented to the public.

The real problem is that the public, and
creationists, do not understand what evolution is all about.

This person's definition of evolution was very
different from the common scientific definition
and as a consequence he was unable to understand
what evolutionary biology really meant.

This is the same person who claimed that one
could not "believe" in evolution and still be religious!

But once we realize that evolution is simply "a
process that results in heritable changes in a
population spread over many generations" it seems
a little silly to pretend that this excludes religion!

Scientists such as myself must share the blame
for the lack of public understanding of science.
We need to work harder to convey the correct information.

Sometimes we don't succeed very well but that
does not mean that we are dishonest. On the other
hand, the general public, and creationists in
particular, need to also work a little harder in
order to understand science. Reading a textbook would help.

<http://www.talkorigins.org/faqs/evolution-definition.html>http://www.talkorigins.org/faqs/evolution-definition.html

<http://www.freerepublic.com/focus/news/1652400/posts?page=2#2>2
posted on 06/20/2006 10:15:35 AM EDT by
<http://www.freerepublic.com/focus/news/1652400//~matchettpi/>Matchett-PI
http://www.freerepublic.com/focus/news/1652400/posts?page=2#2

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Received on Thu Jun 22 08:45:54 2006