Judging from orthodox
Darwinian theory, we should expect to see fossils
appearing in larger and larger sizes, at a steady rate of
progression between 2 billion years ago and 100 million years ago.
But the fossil record shows no such thing. Instead, we see very
little fossil evidence of life prior to the Cambrian era about 540
million years ago. But during the Cambrian era (between about 540
million years ago and 485 million years ago), there is a sudden surge
of fossils in the fossil record. This sudden blossoming of life
during the Cambrian era is known as the Cambrian explosion. This
sudden surge is quite a problem for orthodox biological theory.
The
largest categories of life are called phyla. Most of the major phyla
first appear in the fossil record during this relatively short
Cambrian era. The Cambrian explosion may be described as an
information explosion or a body plan explosion. The Earth seems to
have suddenly got implementations of all these body plans there was
no sign of before. How could that have happened?
An
article on February 16th
in the journal Nature
seems to suggest that a solution to this great puzzle may be near.
The article headline says the following:
An
evolutionary burst 540 million years ago filled the seas with an
astonishing diversity of animals. The trigger behind that revolution
is finally coming into focus.
But
when we read the article we are disappointed. The only “trigger”
described is a rather slight increase in oxygen. That's hardly an
explanation for this astonishing information explanation. The
article covers up the difficulty by completely failing to even
mention that the sudden appearance of such a large variety of highly
developed animals in the fossil record is a difficulty for the
prevailing account of evolution.
Imagine
if you and your spouse go out to a movie. You come back and see on
your dining room table there are several freshly typed books
describing the US and its cities. You are puzzled: where did this
come from? But suppose your spouse suggests this answer: the
explanation is that the books are written on paper that she only
bought this morning; so the reason they appeared is that only today
was there the paper the books needed. That would be a ridiculously
inadequate explanation for the appearance of the books. Generally you
don't explain the appearance of something merely by mentioning that
one of its prerequisites was met at some particular time. Similarly,
we cannot explain the sudden appearance of highly developed animal
forms by just mentioning that at some particular point one of the
prerequisites for such things was met.
The
Nature
article also seems to have advanced a dubious factual claim, that
there wasn't enough oxygen prior to the Cambrian period beginning 540
million years ago. A recent scientific paper authored by ten
scientists is entitled, “Sufficient oxygen for animal respiration
1,400 million years ago.” The paper states: “We suggest that
there was sufficient atmospheric oxygen for animals long before the
evolution of animals themselves, and that rising levels of
Neoproterozoic oxygen did not contribute to the relatively late
appearance of animal life on Earth. ”
The
Nature article is an example of a type of science journalism we see
again and again: what I may call the “Explanation is coming”
story or the “We're on the brink of explaining this” story. It
is as if such articles were written according to the lesson plan
shown below.
Various
versions of these “We're on the brink of explaining this” stories
have been appearing for more than 50 years. For more than 45 years
I've been reading occasional stories suggesting that scientists are
on the brink of solving the mystery of the origin of life. They
actually seem to be ages away from solving such a problem. For more
than 45 years I've been reading occasional stories suggesting that
scientists are on the brink of solving the mystery of consciousness.
Our scientists actually seem to be ages away from solving such a
problem. If you checked the last 40 years of stories on the protein
folding problem, you'd probably read a continual stream of assertions
that the solution is right around the corner. But scientists still
are stumped by the problem.
You
might get the impression from reading these stories that scientists
are getting ever-more-triumphant at explaining things. But it may
well be that something like the opposite is true. There were many
triumphs in explaining things between the year 1850 and the year 1975
(although not all the things that you might list). But in the past 40
years the explanatory triumphs of science seem to have been few and
far between. Can you name one big thing that science has explained
in the past 40 years, something that was not explained by earlier
research? The average person probably can't think of anything.
Applied science (pretty much the same as technology) is doing very
well, but explanatory science may be sputtering.
It
could be that the predominant “bottom-up” approach toward
scientific explanation is running out of gas. There is only so far
you can go at trying to explain things by trying to describe how
little things can add up to big things or by trying to explain a
whole just by mentioning the action of its parts. We need to think of
more “top-down” explanations in which deep and grand principles
cause the things that we are trying to explain. Something like
consciousness will not be explained by some little bottom-up
explanation involving some nerdy detail of neurons. Our scientists
keep looking for some leverage effect by which piddling little things
can produce magnificent outputs, failing to suspect that behind the
magnificent outputs they are trying to explain may be some equally
magnificent cause.
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