What
we may call the “easy life” crowd is a group that wants to
persuade us that it's easy for life (primitive or advanced) to appear
by chance. A few weeks ago the “easy life” crowd was telling us
that “building blocks of life” had been found on Mars, and that
this greatly increased the chance that life once existed on that
planet. However, as discussed here, the actual organic molecules
found on Mars were neither the building blocks of life nor the
building blocks of the building blocks of life.
This
week the “easy life” crowd is at it again. For one thing, they
are telling us that the “building blocks of life” have been found
on Enceladus, a moon of Saturn. A page on Fox News has the
headline “Scientists have found the 'building blocks for life' on Saturn's moon
Enceladus.” But this claim is as inaccurate as the claim about
building blocks of life on Mars.
The
claims are based on a scientific paper that does not claim to have
discovered any molecules with a molecular weight much larger than
about 200 atomic mass units. The building blocks of life are things
such as proteins and nucleic acids. The average protein has hundreds
of amino acids, and an amino acid has a molecular weight of about 100
atomic mass units. So a protein has a molecular weight of about 20,000
or more. That's 100 times bigger than the molecules detected on
Enceladus.
Enceladus (Credit: NASA)
Until some scientist reports detecting something with a
molecular weight of more than 10,000, no one should be claiming that
“building blocks of life” have been detected on Enceladus.
Although the organic molecules detected on Enceladus have a molecular
weight about the same as the molecular weight of an amino acid (one
of the building blocks of proteins), the exact nature of these
molecules is unknown, so we don't know whether any of them is actually an
amino acid. So it cannot even be truly said that even the building
blocks of the building blocks of life have been detected on
Enceladus.
This
week's other example of specious spin by the “easy life” crowd
comes in the form of an article in Science magazine entitled
“The momentous transition to multicellular life may not have been
so hard after all.”
The
article begins by stating the following:
Billions of years ago, life crossed a threshold. Single cells started to band together, and a world of formless, unicellular life was on course to evolve into the riot of shapes and functions of multicellular life today, from ants to pear trees to people. It's a transition as momentous as any in the history of life, and until recently we had no idea how it happened.
The
statement “until recently we had no idea how it happened” in
reference to the appearance of multicellular life will come as a
surprise to those who have been told for many decades by scientists
that Darwin's theory of natural selection explained this and all
other biological innovations occurring after the origin of life. So
after many decades of telling us that the appearance of multicellular
life could be explained by mere natural selection and random
mutations, now scientists are claiming “until
recently we had no idea how it happened.” Very fishy indeed.
Our
Science magazine article then states this about the origin of
multicelluarity:
Now,
Nagy and other researchers are learning it may not have been so
difficult after all. The evidence comes from multiple directions.
So
what is this evidence? The first bit of alleged evidence that
multicellularity was easy is described as follows: “The
evolutionary histories of some groups of organisms record repeated
transitions from single-celled to multicellular forms, suggesting the
hurdles could not have been so high.” There is no actual fossil
evidence of any such transitions, and the article gives no example to
back up this claim. Even if we assume that there were multiple cases
of life transitioning from single-celled life to multicellular life,
this would not show that it was easy or something other than fantastically improbable. When we see two
examples of some thing that seems fantastically improbable, that
does not show such a thing is easy, although it may show that more
than luck is involved. For example, if you ask me to guess a
15-digit number you are thinking of, and I do that successfully not once but
twice, that may suggest that something more than luck is involved
(such as ESP), but does not at all suggest that it is easy to guess
randomly chosen 15-digit numbers.
Here
according to the article is the second item of evidence that the
appearance of multicellularity was easy: “Genetic comparisons
between simple multicellular organisms and their single-celled
relatives have revealed that much of the molecular equipment needed
for cells to band together and coordinate their activities may have
been in place well before multicellularity evolved.” But this is no evidence that the appearance of multicellular macroscopic life was easy. It's kind of like arguing that it's easy for a tornado
to blow through an auto parts store and assemble an automobile,
because many of the parts needed for the automobile are lying around in
the auto parts store.
Here
according to the article is the third item of evidence that the
appearance of multicellularity was easy: “And clever experiments
have shown that in the test tube, single-celled life can evolve the
beginnings of multicellularity in just a few hundred generations—an
evolutionary instant.” The article gives a visual of the type of
experiments it is talking about. They are experiments in which a few
microscopic cells are seen to clump together to make an equally
microscopic blob consisting of a few cells adhering together. But
such experiments do nothing at all to suggest that it might be easy
for microscopic life to evolve into visible macroscopic life such as
fishes, trilobites and crabs. You can compare such experiments to
someone waving around a big magnet at an auto parts store. After
getting a few random auto parts stuck to his magnet, the person might
say, “You see – it's easy to form a car by random accumulations
of auto parts.” But such a stunt would not at all prove such a
thing.
On
the basis of these pathetically weak evidence claims, the Science
magazine article claims “multicellularity comes so easy.” No,
the appearance of multicellular organisms such as the many
that appeared suddenly in the Cambrian Explosion is a vast explosion
of information that is not explained by orthodox theories in biology. Big life forms may exist all over our galaxy and the universe, but not if only random, mindless processes are involved.
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