CHEF BOYARDEE AND THE SPAGHETTI-O. . . RIGINS OF LIFE
Jason Machalicky
Writer’s comment:
After putting off the mandatory English requirement for as long as
possible, I finally decided to take English 20, Computer-Aided
Intermediate Composition. When my professor, Pamela Major, assigned the
research paper on a topic of our choice, however, I decided that the
class wasn’t going to be all bad. I had been wanting to write a paper
on creation versus evolution for some time, and I was thankful for this
chance. Inspired by the Microbiology 102 and Evolution 100 classes I
was taking that same quarter, I narrowed down my topic to the origin of
life.
After choosing my topic, I had to figure out how to write
the paper so that I could include upper-division science concepts and
still reach a general audience. I believe that the origin of life is a
topic that all people need to think about, and I do not like
scientists, armed with technical jargon and knowledge, to force a
reader into submission to their views. (It is so easy for a reader to
say, “I don’t understand what he is saying, but he sounds scientific,
so he must be correct.”) In describing some of the difficulties with
current theories about the origin of life, I have tried to both explain
technical concepts without overwhelming the reader and dispel the idea
that science has disproven the existence of God. Though it was
difficult to bring all the information together, it was well worth the
effort to try to do so.
—Jason Machalicky
Instructor’s comment: I’ve always loved a good
footnote! An explanatory footnote at the right moment can add
tantalizing layers to a piece, often both furthering and commenting on
the writer’s argument. But the footnotes are just one example of the
care with which Jason has crafted this truly impressive essay. With
enthusiasm, good humor, and imagination, he undertook the general
directive I gave each student in my English 20 class—to develop over
the quarter a well-researched, well-written paper on a topic that
captures your interest.
To say that Jason chose a difficult topic is, of course,
an understatement. Nevertheless, from journals to proposal to
literature review to numerous drafts, I watched with delight as his
project evolved (no pun intended) into an exceptional essay. In
“Spaghetti-O . . .” Jason has made incredibly complex material
tangible, creating a clear and intriguing argument, whatever one’s
views in the controversy.
—Pamela Major, English Department
How life arose is a
question that is fundamental to both philosophy and science. Responses
to it enable one, in turn, to answer such questions as, “Who am I?”,
“Why am I here?”, and “How do I make sense of this world?” This
secondary set of questions can be answered in a myriad of ways for a
variety of reasons, but the answer to the first question has only two
responses. As Douglas Futuyuma says, “Creation and evolution, between
them, exhaust the possible explanations for the origin of living
things” (197). Either we are the product of the chemical and physical
laws of nature operating over time, or we have been formed, at least in
part, by some supernatural Force or Deity. The acceptance of one of
these options as a foundation will determine how one will establish a
belief system to determine his place in the world. This is a matter of
crucial importance, yet in most biology classes offered at U.C. Davis,
we learn that life came from nonlife by strictly natural (as opposed to
supernatural) processes. The possibility that perhaps the origin of
life cannot be explained by a natural mechanism is ignored, and this is
disturbing. For if we limit what explanations we are willing to accept
for the origin of life, we could be closing our eyes to reality.
Francis Crick, co-discoverer of DNA, has said that “the origin of life
appears to be almost a miracle, so many are the conditions which would
have to be satisfied to get it going” (Horgan 27).2 Noted evolutionary
astronomer Frederick Hoyle has described the chances of life having
evolved from nonlife to be about as likely as the chances that “a
tornado sweeping through a junkyard might assemble a Boeing 747 from
the materials therein” (Johnson 106). Why do respected scientists doubt
what textbooks teach as fact? It would appear that these scientists
know something that current theories describing the origin of life fail
to explain. While current theories describe scenarios in which genetic
material such as RNA becomes entrapped in a protective cell membrane as
a likely recipe for the formation of life, they generally do not focus
on the difficulties of forming and concentrating all of these
components in the first place.3 To clarify, current theories suffer
from what I call the “cookbook mentality.” They say something like,
“Combine brownie mix, eggs, and oil in a bowl. Stir.” But in general,
the theories fail to describe both how those ingredients were actually
made and what agent moved those ingredients from their respective
locations in the kitchen to the mixing bowl. Though experiments that
simulate pre-biotic (before life) conditions have demonstrated the
possibility of forming the building blocks for life, they fail to
accurately represent all that would have happened in the early
atmosphere, especially in regard to the effect of ultraviolet (UV)
light from the sun. In addition, there is reason to doubt whether the
various components produced could have been close enough together,
sufficiently concentrated, to have reacted in meaningful ways.4 These
difficulties are serious enough to lend credence to the idea that life
could not have originated without some form of supernatural
intervention.
To discuss the origin of life, one must first understand the atmosphere
of early Earth. Some four-and-a-half billion years ago, the Earth was
formed. After a period of cooling, the Earth theoretically formed an
atmosphere consisting mainly of hydrogen, methane, carbon monoxide,
carbon dioxide, ammonia, and nitrogen. It is important to note that
this atmosphere lacked oxygen gas, which would have destroyed the
components necessary for life. While this oxygen-less atmosphere,
called a “reducing atmosphere,” would have been toxic to humans, it
would have been hospitable to the formation of organic intermediates,
the precursors to the building blocks of life. Energy sources such as
lightning, heat, shock waves, and UV light from the sun could have
caused the molecules of the primitive atmosphere to form these organic
intermediates and building blocks, which would subsequently have fallen
into the ocean, the famed primordial soup. Further reactions and
thickening of the soup are supposed to eventually have led to the
formation of the main ingredients of life.5
Probably the strongest evidence in support of this scenario has come
from experiments that try to simulate conditions of the early Earth.
Researchers have placed the proposed first molecules in an apparatus
that pushes them through a spark (which represents the energy sources
of the Earth) to make them react, and then collects the newly formed
compounds in a water trap. Through variations on this setup using
different quantities of early atmospheric molecules, scientists have
been able to synthesize most, if not all of the building blocks of
life.6 These building blocks include amino acids, which can combine to
form proteins; lipids, which can form the cell membrane; and various
sugars that can either serve as a food source or combine with other
molecules to form nucleotides, the building blocks of genetic material
(e.g., RNA or DNA). After a further set of chemical reactions, it is
theorized that the proteins and genetic material could aggregate inside
a cell membrane, eventually forming a living entity (Zimmer 78).
Though experimental evidence demonstrates that organic intermediates
and some building blocks could have formed in a pre-biotic atmosphere,
two questions remain: Could sufficient quantities of these molecules
have been produced to participate in reactions that would promote the
formation of life? And, if so, would they have been close enough
together to have reacted with one another? After all, the ocean is a
pretty big place. One can’t just plunk an amino acid into water and
expect it to react with another amino acid fifty feet away. Either
there has to be an abundance of amino acids in the ocean or there has
to be some way of concentrating them—in a tide pool or lake, for
example. Can we really demonstrate that on the early Earth enough
molecules could have congregated and subsequently carried on reactions
that they eventually would have led to the production of life? Not
without a leap of faith that is more blind than rational. Here is why.
First, one of the assumptions behind experiments that simulate
pre-biotic conditions is that energy forms present in those times
caused reactions between the first molecules of the atmosphere. These
first molecules interacted to form intermediate organic compounds that,
with enough energy, could have formed the building blocks of life
(biomonomers); in other words, direct absorption of energy organized
simple molecules into more complex arrangements. Energy alone, however,
is not necessarily sufficient to increase the complexity or
organization of a bunch of molecules (Thaxton 43). To illustrate, one
might expect a bull in a china shop to have either destructive effects
or no effect at all (if it just walked out). We certainly wouldn’t
expect the bull to mold a saucer into a salt shaker! In the same way,
energy sources most likely destroyed, rather than shaped, the
components of the early atmosphere into more complex structures.
Ultraviolet light from the sun is a good example of this proverbial
bull. In a primitive atmosphere without the oxygen-formed ozone layer,
UV light would have destroyed most of the molecules and intermediates
suspected of composing the Earth’s early atmosphere. For instance, it
would have destroyed methane’s chances of meaningful activity by
causing methane (and other hydrocarbons) to disassociate and form
either a very complicated mixture (a tar) or such simple, rather stable
molecules as carbon dioxide and water (Cairns-Smith 42). In other
words, it would have produced road pavement, not life. UV light also
would have degraded 99% of the atmospheric formaldehyde into carbon
monoxide and hydrogen gas. (Formaldehyde is a key intermediate in
origin-of-life experiments because it can participate in further
reactions to yield building blocks such as amino acids and sugars.)
Last, solar UV radiation would have degraded another important
atmospheric component, ammonia, into nitrogen and hydrogen, reducing
the concentration of ammonia to “so small a value that it could have
played no important role in chemical evolution” (Thaxton 43).
As we’ve seen, UV light would have destroyed several of the key
components of the early atmosphere. Without these molecules, crucial
intermediates could not have formed, and without the intermediates, the
building blocks of life would be in very short supply. Even if the
building blocks of life had somehow formed, however, they too would
have been subject to UV destruction. For amino acids, the building
blocks of proteins, “it has been estimated that perhaps no more than 3%
of the amino acids produced in the upper atmosphere could have survived
passage to the ocean” (De Hull, qtd. in Thaxton 45). It is also well
known that UV light destroys the replicative properties of nucleic
acids, the building blocks of genetic material (Lehninger 345). Current
theories are beginning to acknowledge these problems and to propose
instead that meteorites and cosmic dust could have delivered the
various building blocks straight to the ocean. Yet the ocean would not
have been a safe haven either, since UV light penetrates tens of meters
below the ocean surface (Sagan 198). Even those building blocks that
did escape to deep enough water would still have been at risk since
ocean currents would periodically have surfaced even deeper waters.
Obviously, the destructive force of UV light in the primitive
atmosphere would have been formidable—so formidable that contemporary
organisms would have acquired a mean lethal dose of UV radiation in 0.3
seconds (Sagan 197). But not all molecules are subject to UV
degradation. For example, hydrogen cyanide, perhaps “the most important
intermediate leading to the origin of life” (Thaxton 48) because of its
role in forming nucleic acids and some amino acids, resists degradation
by UV light. In sufficiently concentrated solutions (0.27 grams per
liter) it could have led to the formation of life’s building blocks.
Unfortunately, the highest average concentration of hydrogen cyanide in
the early ocean is given to be 2.75 X 10-5 grams per liter. In such a
low concentration, hydrogen cyanide would preferentially react with
water and get ruined. Thus “it is very unlikely that HCN [hydrogen
cyanide] could have played a significant role in the synthesis of
biologically meaningful molecules in an oceanic chemical soup” (Thaxton
49).7 It is hard to envision any way in which hydrogen cyanide could
have accumulated in some little pool without first being ruined.
At this point, we have seen that components of the early atmosphere
would have had little chance to combine and form organic molecules
because UV radiation would have destroyed both them and the organic
building blocks they would have produced. We have also noted that the
important molecule hydrogen cyanide could not have played a significant
role in forming organic building blocks. Scientists acknowledge these
difficulties and instead propose that organic molecules and building
blocks could have aggregated in little pools on the land, in bubbles,
or on clay particles. Of course, by whatever method they were
concentrated, any organic molecules could not have been exposed to UV
light.
Suppose that these organic molecules could have formed and collected in
some protected region. So now we have a pool or a bubble or a clay
aggregate containing significant quantities of aldehydes, ketones,
sugars, amino acids, and even nucleotides.8 Now we’re well on the road
to producing proteins, DNA, and all the other components for life,
right? Wrong. Though our goal is to have each component react only with
other components of the same type (e.g., amino acids reacting with each
other to form proteins and nucleotides reacting with each other to form
genetic material), in reality, they all would have reacted with one
another to form useless conglomerations of organic garbage. For
example, both individual and chains of nucleotides and amino acids
would have reacted with formaldehyde, an important intermediate
molecule, and subsequently would have lost their use as building blocks
to protein and genetic material, respectively.9,10 The only way to
reverse this attachment is to boil the complex in acid—an unlikely
option on early Earth. This means that we would end up with useless
organic material that could be restored to its original useful
components only with great difficulty (Thaxton 50).
The significance of all of these useless chemical interactions might be
described in terms of an analogy. Let’s say we have a bowl of randomly
mixed Legos and some of them, the blue ones, are coated with
super-glue. Each color of Lego will represent one specific organic
intermediate or building block. (The red ones are amino acids, the
white ones are nucleotides, etc.) By just shaking the bowl of Legos, we
need to maneuver all the same-colored Legos together without getting
any other Legos stuck between. Now, shaking the bowl isn’t going to
attach any Legos for us; to do that we are allowed to reach into the
bowl with our eyes closed every couple of seconds and attach a few
Legos that are next to each other. This attaching event will represent
the random combination of compounds due to energy input from the
primitive atmosphere. Though we would like to connect only same-colored
Legos, it is much more likely that we will generate a useless rainbow
stack, especially considering that shaking a bowl will not do much to
segregate the Legos by color. And even if we did manage to push
together a stack of, say, all white blocks, a super-glue-covered, blue
Lego could still come and attach to it (without our intervention) and
destroy any functional potential of the stack. Of course, this analogy
is a vast simplification of a pre-biotic scenario, but it is this sort
of problem that current origin theories fail to solve.
Actually, the chances of forming a viable protein from a concentrated
pre-biotic soup are far worse than I have described them. First,
remember that amino acids are the building blocks of proteins. There
are more than 500 kinds of naturally occurring amino acids, and all
species use only about 20 of those kinds to form proteins (Vollhardt
1024). Presumably, in a pre-biotic environment, hundreds of
nonproteinaceous amino acids could have formed and could have combined
with a proteinaceous amino acid chain. So not only do we have to figure
out how amino acids could have conglomerated; we also have to figure
out how the proteinaceous amino acids avoided bonding with the
non-proteinaceous ones. Though it is possible that (had things worked
out differently in the formation of life) those amino acids we call
“nonproteinaceous” could have been proteinaceous, this point still
should be kept in mind, especially considering that no one to my
knowledge has ever demonstrated that functional proteins can be formed
from nonproteinaceous amino acids.
Yet another difficulty in the formation of proteins has to do with the
shape of the amino acids that form them. Nineteen of the twenty
proteinaceous amino acids come in two forms, a left-handed version and
a right-handed version.11 In most species, proteins are made up solely
of the left-handed version, called L-amino acids. This fact amazes
scientists and, as far as I know, there are no known species that
contain proteins with a mixture of the two amino acid versions
(Lehninger 114). The reason this is so amazing to scientists is that on
the pre-biotic Earth, equal quantities of both versions of amino acids
would have been present. How could proteins containing only one version
of the amino acid have been formed? In a primordial pool, a growing
polypeptide would have incorporated both amino acid versions and formed
a useless molecule. Yet, inexplicably, it didn’t happen that way. No
theories that I know of even attempt to explain this mystery.
As we have seen, it would have been exceedingly difficult to have
assembled a protein that contained all the same version of
proteinaceous amino acids. Let’s just say, however, that we managed to
string together a sequence of amino acids that met all the
requirements. Not only that, but let’s say that the sequence of amino
acids just happened to code for a functional protein.12 Does this mean
we would actually have obtained a functional protein? Unfortunately,
no. Proteins are more than just a string of amino acids. In order to
form a functional protein, the string of amino acids must fold and
twist into a specific three-dimensional shape (conformation). And the
vast majority of proteins cannot fold into their proper conformation on
their own; they need help from specialized proteins called chaperones
or hsp’s (Alberts 214). Okay, what if we happened to form a string of
amino acids that coded for a chaperone protein?13 Couldn’t that
sequence fold up on its own and subsequently help other amino acid
sequences to fold properly? No, chaperones cannot fold up on their own
either. They need help from another specific type of protein to fold
properly. Scientists don’t know how far back this need for “helper
proteins” goes (Crow, personal communication), but the requirement
dashes the hopes of those who believe that proteins were the first step
in the formation of life.
Leslie Orgel and David Deamer have proposed alternatives to the
protein-first theories. Instead of forming proteins, Orgel proposes
that genetic material such as RNA could have formed first when random
nucleotides combined.14 Enzymatic RNA (called ribozymes), along with
inorganic catalysts (certain minerals), could have done some sort of
primitive RNA replication without the need for proteins.15 If this
possibility for RNA replication is correct, Orgel reasons, then the
main problem left for scientists would be to determine how the RNA came
into being.16 If some form of self-replicating genetic material could
have formed, biophysicist David Deamer theorizes that the genetic
material could have been protected from destructive chemical reactions
in stable lipid bilayers. (Lipid bilayers form the outer boundary of
some cells). Further experimentation has demonstrated that a
“quasi-cell” made up of genetic material in a lipid bilayer could have
taken in inorganic ions, nucleotides, and amino acids. With the
addition of a complex enzyme called RNA polymerase, it could have been
possible to make strands of RNA in the cell.17 This is still far from a
real cell, Deamer acknowledges, but it is a step in the right
direction. Unfortunately, even these current theories suffer from the
“cookbook mentality” and fail to adequately resolve the crucial
problems I have raised.
It is reasonably safe to say that life could not have originated on
this planet as a result of strictly natural physical and chemical
processes operating over time. We have seen that these processes would
most likely have led to the destruction of key components of the
pre-biotic Earth and, on the off chance that organic compounds could
safely have concentrated, to the nearly irreversible formation of
useless organic garbage. Scientists who wish to perpetuate the view
that life could have originated by strictly natural processes need to
find a mechanism that would both concentrate and segregate specific
organic compounds. Then each type of building block could react only
with other blocks of the same type, without any side reactions. I have
not come across any model that proposes a way to accomplish this. Until
scientists can come up with a way to demonstrate the possibility of
this phenomenon, it is not logical to claim that, with enough time,
“the improbable became inevitable” (Lehninger 77). Time alone is not a
sufficient explanation for such an amazing feat of organization to have
occurred. In fact, time will only make the situation worse as more
Legos get added and contribute to the growing rainbow mess.
Instead of perpetuating the dogma that life must have arisen from
nonlife through strictly naturalistic processes, textbooks should leave
open the possibility that supernatural intervention was essential in
the formation of life. We have seen that textbooks hold on to a
naturalistic explanation for the origin of life by blind faith. At its
worst, the belief in supernatural intervention is on this same level of
blind faith. Though it is frustrating to leave the origin of life to
supernatural forces, it is time for all scientists to acknowledge that
natural forces alone do not appear to be capable of generating the
intricate and immense conglomeration of molecules called life.
Notes
1 Okay, so Spaghetti-O’s are really made by Franco-American.
2 Based on his disbelief in a naturalistic origin of life on
Earth, Crick has theorized that life must have arisen from organic
garbage left here by aliens. (This is called “directed panspermia.”)
3 We’re going to have to establish some terms for these
“components of life.” I use the terms “molecules,” “organic
intermediates,” “building blocks,” and “ingredients” in this paper.
Molecules refers to the original components of the early atmosphere
such as methane, ammonia, and hydrogen gas. Intermediates are formed
when the molecules react together. Examples of these are hydrogen
cyanide and formaldehyde. Intermediates react to form building blocks
(e.g., amino acids and nucleotides), and building blocks stack together
to form the ingredients necessary for life (e.g., proteins and genetic
material such as DNA or RNA). I use “compounds” or “components” in
situations in which I want to keep things general.
4 A low concentration means that the compounds are far apart,
while a high concentration means that they are close together. It is
important to have a high concentration because compounds only react if
they are close to one another.
5 Changes in the soup would involve raising the concentration of the
compounds, either by producing lots of them or by isolating them—in
little pools, for example.
6 As evolutionist Cairns-Smith notes, however, “all such
‘molecules of life’ are always minority products and usually are no
more than trace products. Their detection often owes more to the skill
of the experimenter than to any powerful tendency for the ‘molecules of
life’ to form” (44).
7 Since I have used Thaxton’s book extensively, let me mention
that evolutionists Sidney Fox, David Deamer, and Robert Shapiro, among
others, have given the book favorable reviews.
8 Don’t worry if you don’t know what all these things are; they are just products of some of the origin-of-life experiments.
9 For the organic chemists out there, carbonyl-containing
molecules (ketones, aldehydes, and reducing sugars) react with free
amino groups (of purines, pyrimidines, and amino acids) to form imines,
which are useless for the formation of life.
10 Formaldehyde attaches to three of the five important
nucleotides and ruins base pairing between them. Base pairing is
necessary for replicating genetic material.
11 Molecules that display this “handedness” are called chiral.
L and D amino acids are practically identical, though still different,
just as our right hand appears to be the mirror image of our left,
though it is still different.
12 This is a rather huge assumption. Functional proteins require a
highly specific sequence of the different types of amino acids. Even
minute changes in the sequence could make the protein useless.
13 Honestly, it is nearly impossible to randomly form a
specific protein. Almost every single amino acid would have to be
perfectly located in the sequence. For a chaperone protein, which
consists of 600 amino acids, the probability of getting the correct
amino acid at each of the 600 positions if we just plucked amino acids
from a pool of proteinaceous amino acids at random is around (1/20)600.
Further, a protein needs several chaperone proteins to fold up
properly; one chaperone wouldn’t have done much.
14 Orgel has recently discovered a possible predecessor to RNA, called
PNA. PNA can both self-replicate and serve as a template to form RNA.
While there is no evidence that PNA could have arisen on the early
Earth, Orgel’s discovery at least demonstrates to some the possibility
that simple, self-replicating molecules could have formed. Remember
that formaldehyde would have ruined its replicative properties,
however.
15 While this might be a step in the right direction, it is
very far from anything representing a cell. There is no indication of
how proteins could have arisen from this process. RNA is like a
blueprint: it tells the cell machinery (which consists of proteins)
which amino acids it needs for making proteins. But what good is a
blueprint if there is no cell machinery to use it? (Remember how
difficult it would have been to form specific proteins.)
16 We have already seen how difficult it would have been to
combine nucleotides. Once again, we see that scientists fail to address
the problem of concentrating necessary building blocks. With
nucleotides, there is also the possibility that DNA nucleotides could
combine with an RNA polynucleotide. This would be like D-amino acids
combining with an L-amino acid polypeptide. We have never seen that
genetic material composed of mixed types of nucleotides could be
functional.
17 I do not know enough about Deamer’s work to criticize it
too much. I do want to mention that the formation of RNA polymerase
would have been next to impossible. The simplest RNA polymerase is
composed of four protein subunits—two alphas, a beta, and a beta’. (It
also needs a subunit called the sigma factor, but I’m not even going to
get into that.) We have already discussed how difficult it would have
been to form one protein. Imagine forming two identical proteins and
two others perfectly, all in the same location. The odds against this
are astronomical, especially considering that each subunit is made up
of about 1,000 amino acids. And, of course, even if this miracle did
occur, we still would need functioning chaperone proteins to give the
subunits their proper shapes and combine them.
Works Cited
Alberts, Bruce, et al. Molecular Biology of the Cell. New York: Garland, 1994.
Brock, Thomas D., et al. Biology of Microorganisms. Englewood Cliffs, NJ: Prentice Hall, 1994.
Cairns-Smith, A. G. Seven Clues to the Origin of Life. Cambridge: Cambridge UP, 1985.
Crowe, John. Personal Communication. March, 1996.
De Duve, Christian. “The Constraints of Chance.” Scientific American January 1996: 112.
Denton, Michael. Evolution: A Theory in Crisis. London: Burnett, 1985.
Futuyuma, D. J. Science on Trial. New York: Pantheon, 1983.
Hickman, Cleveland P., Jr. Integrated Principles of Zoology. Wm. C. Brown Communications, 1995.
Horgan, John. “The World According to RNA.” Scientific American January 1996: 27-30.
Johnson, Philip. Darwin On Trial. Illinois: Intervarsity Press, 1993.
Lehninger, Albert L., et al. Principles of Biochemistry. New York: Worth, 1993.
Morris, Henry, and Gary Parker. What Is Creation Science? San Diego: Creation- Life Publ., 1987.
Orgel, Leslie E. “The Origin of Life on Earth.” Scientific American, October 1994: 77-83.
— , et al. “Template Switching Between PNA and RNA Oligonucleotides.” Nature, August 1995: 578-81.
Sagan, Carl. “Ultraviolet Selection Pressure on the Earliest Organisms.” Journal of Theoretical Biology (1973), 195-200.
Thaxton, Charles, et al. The Mystery of Life’s Origin: Reassessing Current Theories.
New York: Philosophical Library, 1984.
Vollhardt, K. Peter C., and Neil E. Schore. Organic Chemistry. New York: W. H. Freeman, 1994.
Zimmer, Carl. “First Cell.” Discover, November 1995: 69-79.