When
33 scientists released their interesting paper “Cause of Cambridge
Explosion – Terrestrial or Cosmic?” the paper received fairly
little attention. That's too bad, because it was an interesting
paper fearlessly challenging biological orthodoxy. But now the paper
has attracted new attention. Inspired by a speculation in the paper
by the 33 scientists, someone released a news story with a headline
saying octopuses may have come from space. The excitement may have
got started with this outrageous headline from the British tabloid
Express:
The tabloid's dubious headline
This,
of course, was not actually “science news,” but merely a report
about a very speculative idea presented in the paper about the
Cambrian Explosion written by the 33 scientists. Let's take a look
at the wider theory advanced by these scientists, and some reasons
why it comes up short.
The
theory is that various biological innovations in Earth's past
occurred after comets dumped biological material on our planet. One
of the great unsolved mysteries of biology is why there was such a
massive amount of biological innovation occurring about 540 million
years ago in the event called the Cambrian Explosion. During this
relatively short period of time, most of the animal phyla now
existing originated. For reasons discussed here, such an event has always been hard to reconcile
with Darwinian ideas of slow, gradual evolution.
The
33 scientists suggest a strange possibility: that life originated in
comets, and that during the Cambrian Explosion our planet may have
passed through a cloud of comets. If life had existed on many of
these comets, this may have provided our planet with a surge of new
biological information. The authors state the following:
It
takes little imagination to consider that the pre-Cambrian mass
extinction event(s) was correlated with the impact of a giant
life-bearing comet (or comets), and the subsequent seeding of Earth
with new cosmic-derived cellular organisms and viral genes (Hoyle
and Wickramasinghe, 1979,
1981).
There may indeed have been a complex comet debris stream implying
multiple impacts over the estimated 25 million years at the start of
the Cambrian explosion.
The
authors also suggest that cometary impacts had something to do with
the origin of the octopus. The
authors point out that “the
genome of the Octopus shows a staggering level of complexity with
33,000 protein-coding genes more than is present in Homo sapiens.”
The authors state this:
The
transformative genes leading from the consensus ancestral Nautilus
(e.g. Nautilus
pompilius)
to the common Cuttlefish (Sepia
officinalis)
to Squid (Loligo
vulgaris)
to the common Octopus … are not easily to be found in any
pre-existing life form – it is plausible then to suggest they seem
to be borrowed from a far distant “future” in terms of
terrestrial evolution, or more realistically from the cosmos at
large. Such an extraterrestrial origin as an explanation of emergence
of course runs counter to the prevailing dominant paradigm.
Later
the authors state the following, using “bolides” as a synonym for
comets:
It
is certainly an interesting idea that various “information
explosions” or “complexity explosions” we see in the history of
life might be explained by biological material coming from comets.
And the 33 authors are quite right in hinting that such cases are inadequately explained by Darwin's theory of evolution, which offers only
the explanation of random mutations and natural
selection, one that is weak and unconvincing for reasons discussed here. An event such as the Cambrian Explosion in which we see
the rather sudden appearance of most of the existing animal phlya
(with so many new body plans appearing suddenly) is something that
seems to be impossible to explain while you are confined by the
straight-jacket of Darwinian orthodoxy. However, there are two very
big problems in the type of theory suggested by the 33 authors.
The
main problem has to do with the genetic code. The genetic code is the
very specific system of representations used by all earthly life. It
is not at all true that this genetic code follows inevitably from
some laws of chemistry. The genetic code used by earthly organisms is
only one of thousands of possible genetic codes that life might have
been based on.
The genetic code
So
let us imagine that life appeared independently on different comets
in our solar system. The life on each such comet would have its own
genetic code. If life were to develop on a comet, and that comet were
to crash to our planet, such life would be using a genetic code
entirely different from that of the earthly life that existed before.
If there had been multiple collisions of life-bearing comets on
Earth, what we would expect is a variety of organisms using different
genetic codes. It might, for example, be that 50 percent of life used
one genetic code, and 20 percent of life used some other genetic
code, and 30 percent of life used some third genetic code. Or there
might be ten different genetic codes used by earthly life. But that's
not what we see. All life on Earth seems to use the same genetic
code.
A
writer named Gert Kortof states the problem in reviewing a book by
Fred Hoyle:
Why
is it a problem that the genetic code of the extraterrestrials and
terrestrials should be the same? Is the code not necessarily derived
from the laws of chemistry? No, it isn't! The genetic code is not a
universal cosmic code. The problem with any theory that claims
extraterrestrial genetic input, is that life on Earth is a closed
genetic system. I strongly disagree with Hoyle's claim that
"terrestrial
biology is not a closed system".
(p. 3) Why? All Life on earth happens to have the same genetic code.
That would be no problem, if it would be the only possible genetic
code available to life. Our genetic code is one of billions and
billions of possible codes. The current one looks like a 'frozen
accident'. The probability that the genetic code of extraterrestrial
DNA is the same as the genetic code on earth, equals the chance that
a Boeing-747 arises from a junk yard!
Therefore
it is very hard to believe that various comets on which life
independently developed have seeded our planet with new life forms.
If that had happened, it would not be true that all life uses the
same genetic code. The issue of the genetic code is ignored by the
paper by the 33 scientists.
A
second problem is that comet collisions would be extremely
destructive to earthly life. A comet impact would not be as
destructive as an asteroid impact. But a larger comet might have so
much kinetic energy that it might cause a mass extinction if it
collided with our planet. A scientist says here that a collision with
a kilometer-sized comet would probably mean the end of civilization.
The chance of life on a comet surviving such an impact does not seem
very great. It seems that a comet collision would be likely to
destroy far more species than it added to our planet because of an
addition of life from the comet.
Does
this mean that the idea of extraterrestrial inputs to earthly biology
should be discarded and dismissed? Not at all. There is a variation
of this idea that gets around the genetic code problem and the
collision problem. We can simply
hypothesize that rather than being accidental, random inputs from
comets, the extraterrestrial inputs were deliberate inputs from
intelligent extraterrestrial visitors.
Instead
of life-bearing comets arriving at various times in the past, we can
imagine life-bearing spaceships arriving here at various times in
earth's history. Imagine if the beings populating an extraterrestrial
expedition to our planet were to try to speed up the evolution of
life on Earth. If such astronauts were to design new organisms to
introduce on our planet, they would presumably create designs using
the genetic code already used on our planet, rather than using some
genetic code coming from their own planet (just as someone visiting
Japan from England trying to spread ideas to the Japanese would
create books written in Japanese rather than English). And of
course, under such a spaceship theory the astronauts would not be
smashing their spaceships into our planet, so you avoid the collision
destruction problem. So by imagining a purposeful, directed
introduction of new life forms into the Earthly biosphere, we have a
“life from space” theory that avoids the two big problems of the
theory of the 33 scientists.
But
such a smarter theory might have been avoided by the 33 scientists on
the grounds that it would be hard for a paper advancing such a theory
to get published, given the current state of biological academia
where there exists ideological restrictions that sometimes seem as
great as those in a medieval monastery. For it is a great taboo in
colleges and universities for anyone to be talking about purpose,
design, and deliberate intent when trying to explain the origin of
Earth's living things.
This
taboo makes no sense at all. It is the taboo that when discussing the
origin of incredibly fine-tuned biological organisms that look just like products of design and purpose, we must
never suggest any explanation that involves some purposeful cause.
It is the taboo that when discussing biological functionality more
impressive than any electronic functionality man has produced, we
must always pretend that all these biological innovations were mere
accidents. And so our 33 scientists have given us a theory with two
giant holes, huge problems that could have been avoided by simply
imagining purposeful extraterrestrial visitations rather
than purposeless extraterrestrial comet collisions.
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