The online science magazine Nautilus sometimes gives its
readers impressions that are completely at odds with reality. Based
on many articles Nautilus has had on the multiverse, you might think
that this is a well-confirmed scientific concept. But to the
contrary, there is not a speck of evidence for any multiverse or any
universe beyond or own. There are also very good reasons for thinking
that no such evidence could possibly appear, given that any observations that
we could possibly make would always be observations of our own
universe, not an observation of some other universe.
Another area in which Nautilus creates an impression
completely at odds with reality is the origin of life. An article by
astrobiologist Nathaniel Comfort in the current edition of Nautilus
has a subtitle telling us that “Hydrothermal vent models transform
the origins of life from unlikely to near-inevitable.” The text of
the article goes even further, stating this:
Vent
models posit that given the initial conditions, the emergence of life
was not a near-miracle. It was inevitable.
This
statement gives the reader a very wrong idea. Any realistic
appraisal of the origin of life must regard it as the most improbable
type of event, basically a miracle. To
calculate the odds of such a thing, we must consider all of the insanely
improbable things that seemed to be required for life to originate
from non-life. It seems that to have even the most primitive life
originate, you need to have an “information explosion.” Even the
most primitive microorganism known to us seems to need a minimum of
more than 200,000 base pairs in its DNA (as discussed here).
Protein molecules have to be just-right to be functional. It has been
calculated that something like 1070
random trials would be needed for a functional protein molecule to
appear, and many such protein molecules are needed for life to get
started. And so much more is also needed: cells, self-replicating
molecules, a genetic code that is an elaborate system of symbolic
representations, and also some fantastically improbable luck in
regard to homochirality.
Postulating
hydrothermal vents as the spot where life originated does nothing to
help with these problems. A hydrothermal vent could supply some
heat. But a lack of heat was never the issue. The issue was the appearance of life requires a very high degree of organization and functional coherence that should have been fantastically improbable to have occurred by chance.
By claiming that life appeared at hydrothermal vents, it seems that you are sharply decreasing the odds of life appearing, not increasing them. As the map below shows, hydrothermal vents are found on only a tiny fraction of the ocean's surface, at the bottom of the ocean. A person assuming that life might have originated anywhere in the ocean would be assuming perhaps 100,000 times more volume of space for chemical reactions to occur.
By claiming that life appeared at hydrothermal vents, it seems that you are sharply decreasing the odds of life appearing, not increasing them. As the map below shows, hydrothermal vents are found on only a tiny fraction of the ocean's surface, at the bottom of the ocean. A person assuming that life might have originated anywhere in the ocean would be assuming perhaps 100,000 times more volume of space for chemical reactions to occur.
Credit: NOAA
To
support his “easy life” insinuations, Comfort cites a scientific
paper using the word “dissipation” or “dissipative” 18 times.
Comfort also gives us a little thermodynamic mumbo-jumbo centered
around the idea of dissipation. He states the following:
As some type of attempt to
explain the origin of life and increasingly complex biology, this thermodynamic twaddle
is a complete bust, and we can laugh at the loopy statement, “Our
biosphere is but a sophisticated icepack for the sun.”
The term dissipation is defined as “squandering of
money, energy, and resources.” Such a concept does nothing to
explain biological organization. If some chemicals become organized
into a life form, that is the opposite of dissipation. Far from
helping us out in regard to the origin of life, the second law of
thermodynamics just gives a reason for thinking that such a thing is
all the more unlikely. The second law of thermodynamics says entropy
or disorder always increases as times goes on. If we have life
appearing and becoming ever more organized, that is a trend that is disfavored (but not prohibited) by the second law of thermodynamics, rather than
something favored by it. Far from being thermodynamically favored,
each increase in biological order is thermodynamically disfavored. Similarly, each step you take up a stairs is disfavored (but not prohibited) by the law of gravity.
You can summarize the second law of thermodynamics like this: it likes anything that involves a dissipation or dispersion of heat, but doesn't like anything that involves a concentration of heat. Because life forms are a concentration of heat, they are thermodynamically disfavored. Things that are thermodynamically favored are things like a fire burning out, a hot object cooling down, and the sun eventually burning out.
You can summarize the second law of thermodynamics like this: it likes anything that involves a dissipation or dispersion of heat, but doesn't like anything that involves a concentration of heat. Because life forms are a concentration of heat, they are thermodynamically disfavored. Things that are thermodynamically favored are things like a fire burning out, a hot object cooling down, and the sun eventually burning out.
The idea that hydrothermal
vents would have made the origin of life likely is busted in this
statement by origin-of-life scientist Nick Lane:
Comfort seems to favor the
“easy life” hypothesis, which claims that the origin of life was
for some reason inevitable or all-but-inevitable. There are many
reasons for thinking that such an idea is not correct. The main
reasons are all of the difficulties in explaining the giant leap in
complexity, information and organization involved in moving from
non-life to even the simplest living thing.
Another reason for
rejecting the “easy life” hypothesis is that despite more than 65
years of laboratory research, no one has been able to artificially
create life in a laboratory. If it were true that the origin of life
was thermodynamically favored, then it wouldn't be too hard to create
an origin-of-life experiment which produced life from non-life.
Still another reason for
rejecting the “easy life” hypothesis is the failure of SETI (the
Search for Extraterrestrial Life). If the origin of life was somehow
thermodynamically favored or all-but-inevitable, then the whole
galaxy would be teeming with life, and odds might have favored
searching for radio signals from extraterrestrial civilizations. But
after decades of effort checking many thousands of sun-like stars, no
such signals have been found.
Still another reason for
rejecting the “easy life” hypothesis is that such an idea implies
that life would have originated on Earth many times. If it was “all
but inevitable” that life would originate, there should have been
many separate origins of life. But the total number of times in which
life has naturally originated on our planet seems to be no greater
than 1. All earthly life uses the same genetic code. We see no
organisms using a different genetic code. But imagine if life had
independently originated multiple times on Earth. Then we would see
various types of life that each used a different genetic code.
People sometimes argue
that if there had been a second origin-of-life on Earth, then life
based on that second origin would have been gobbled up by whichever
life appeared first. But that's not a good argument. Imagine if
these two things happened:
3,700,000,000 years
ago: life originates using one genetic code, resulting in
Biosphere 1
3,600,000,000 years
ago: life has a separate origin using a different genetic code,
resulting in Biosphere 2
In this case would the
organisms of Biosphere 1 just destroy the organisms of Biosphere 2
through predation? No, since they both would use a separate genetic
code, they would be incompatible. The organisms of Biosphere 1 would
not be able to consume the organisms of Biosphere 2 – or, if an
organism of Biosphere 1 ate an organism of Biosphere 2, it would not
find it nutritious, because it would be using an alternate chemistry.
So rather than Biosphere 2 disappearing because Biosphere 1 had a
head start, the two biospheres would both exist.
There is no evidence of a second biosphere, and life seems to have not naturally originated on our planet more than once. Such a thing argues strongly against the "easy life" claim that the origin of life was inevitable or almost inevitable.
Postscript: It is inaccurate for Comfort to be claiming that certain models posit that the origin of life was inevitable. While some of the authors of the papers that he references may have made optimistic statements about the origin of life, neither a mathematical model nor any set of equations could ever show the origin of life was likely. There is no way to put "life" or "a living cell" on the right side of an equation. You could in theory have an experiment or a computer simulation that might show a likely origin of life, but none of the papers that he references involves such a thing.
If a person tries to appeal to human beings or some other life form as a superior agent of heat dissipation, and then tries to suggest that such things are likely on the grounds of the second law of thermodynamics, such a person is committing a kind of fallacy like the fallacy in the reasoning below:
"The law of the wind is a kind of law of dispersion. Wind likes to scatter things far apart. So the wind would bring various things together to make bombs. Because those bombs would be really good at dispersion, at scattering things far apart."
This reasoning is fallacious. The "law of dispersion" followed by the wind is not precognitive or intelligent. Such a law is too dumb and short-sighted to first bring things together because this will later eventually serve some goal of causing a high degree of blowing things apart. Similarly, the second law of thermodynamics will act in a way that is completely short-sighted and lacking in any foresight, intelligence or precognition. It makes no sense to postulate that such a law will create things of concentrated heat and low entropy (living things) because such things might eventually engage in dissipation effects that result in heat dissipation and higher entropy. Life forms are a concentration of heat, and there is no concentration of heat that is favored by the second law of thermodynamics.
"Easy life" theorists sometimes cite the work of Jeremy England, an MIT Professor. A Harvard professor says, "Jeremy’s work represents potentially interesting exercises in non-equilibrium statistical mechanics of simple abstract systems," but says that any claims it is has to do with biology or the origin of life is "pure and shameless speculation."
After quite a few absurdly immodest articles have appeared about his work, England seems to have got more modest. "I would not say I have done anything to investigate the 'origin of life' per se," he now says. He says, "If, when you say 'life,' you mean stuff that is as stunningly impressive as a bacterium or anything else with polymerases and DNA, my work doesn't yet tell us anything about how easy or difficult it is to make something that complex, so I shouldn't speculate about what we'd be likely to find elsewhere than Earth."
There is no evidence of a second biosphere, and life seems to have not naturally originated on our planet more than once. Such a thing argues strongly against the "easy life" claim that the origin of life was inevitable or almost inevitable.
Postscript: It is inaccurate for Comfort to be claiming that certain models posit that the origin of life was inevitable. While some of the authors of the papers that he references may have made optimistic statements about the origin of life, neither a mathematical model nor any set of equations could ever show the origin of life was likely. There is no way to put "life" or "a living cell" on the right side of an equation. You could in theory have an experiment or a computer simulation that might show a likely origin of life, but none of the papers that he references involves such a thing.
If a person tries to appeal to human beings or some other life form as a superior agent of heat dissipation, and then tries to suggest that such things are likely on the grounds of the second law of thermodynamics, such a person is committing a kind of fallacy like the fallacy in the reasoning below:
"The law of the wind is a kind of law of dispersion. Wind likes to scatter things far apart. So the wind would bring various things together to make bombs. Because those bombs would be really good at dispersion, at scattering things far apart."
This reasoning is fallacious. The "law of dispersion" followed by the wind is not precognitive or intelligent. Such a law is too dumb and short-sighted to first bring things together because this will later eventually serve some goal of causing a high degree of blowing things apart. Similarly, the second law of thermodynamics will act in a way that is completely short-sighted and lacking in any foresight, intelligence or precognition. It makes no sense to postulate that such a law will create things of concentrated heat and low entropy (living things) because such things might eventually engage in dissipation effects that result in heat dissipation and higher entropy. Life forms are a concentration of heat, and there is no concentration of heat that is favored by the second law of thermodynamics.
"Easy life" theorists sometimes cite the work of Jeremy England, an MIT Professor. A Harvard professor says, "Jeremy’s work represents potentially interesting exercises in non-equilibrium statistical mechanics of simple abstract systems," but says that any claims it is has to do with biology or the origin of life is "pure and shameless speculation."
After quite a few absurdly immodest articles have appeared about his work, England seems to have got more modest. "I would not say I have done anything to investigate the 'origin of life' per se," he now says. He says, "If, when you say 'life,' you mean stuff that is as stunningly impressive as a bacterium or anything else with polymerases and DNA, my work doesn't yet tell us anything about how easy or difficult it is to make something that complex, so I shouldn't speculate about what we'd be likely to find elsewhere than Earth."
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