Читать книгу The Truth about Science and Religion - Fraser Fleming - Страница 8

“Science without religion is lame, religion without science is blind” wrote Einstein.15 Pope John-Paul II refocuses Einstein’s idea to show how together the two disciplines work to uncover truth: “Science can purify religion from error and superstition; religion can purify science from idolatry and false absolutes.”16 Nowhere is the intersection of science and religion more divisive than the origin of life and yet this area is where insight is most needed to guide thinking through knotty issues of genetic engineering, cloning, and stem-cell research.

Evolution is probably the greatest source of antagonism between science and religion. For religious people, God made all things. In contrast, biological evolution provides an account of life’s development from inorganic matter without the necessity for any external agent. Evidence from many scientific fields, biology, geology, anthropology, paleontology, and chemistry, provides a highly plausible evolutionary sequence from Big Bang to man. Evolution is not yet supported by seamless evidence from amoeba to zebra, as there are several very significant points awaiting evidence. Nevertheless, scientific advances have been very effective in filling in many details, raising the issue of where God’s influence might be.

An alternative to the explanations of a divinely created young earth or naturalistic biological evolution is an evolutionary process directed by God. Various forms of guided evolution have been proposed, ranging from direct intervention at strategic points, to God being only the initiator of the universe’s evolution. Evaluating the competing theories of earth’s evolution requires objectively examining the fundamental claims of each.

Divine Creation

The opening lines of the Bible set the stage for Christianity’s claim that the Bible’s purpose is to reveal God’s love and desire for all people to live in relationship with him. Sometimes called a hymn, Genesis 1 appears to be a unique blend of prose and poetry. As poetry, the passage uses figurative language to describe God’s activity by using human counterparts: speaking and seeing, working and resting. In reading the first chapter of Genesis, the question to consider is whether a poetic description of the universe’s beginning could provide an accurate description of God’s actions.

Genesis 1: The opening lines of the most published book in the world’s history.

In the beginning God created the heavens and the earth. Now the earth was formless and empty, darkness was over the surface of the deep, and the Spirit of God was hovering over the waters. And God said, “Let there be light,” and there was light. God saw that the light was good, and He separated the light from the darkness. God called the light “day,” and the darkness he called “night.” And there was evening, and there was morning—the first day.

And God said, “Let there be an expanse between the waters to separate water from water.” So God made the expanse and separated the water under the expanse from the water above it. And it was so. God called the expanse “sky.” And there was evening, and there was morning—the second day.

And God said, “Let the water under the sky be gathered to one place, and let dry ground appear.” And it was so. God called the dry ground “land,” and the gathered waters he called “seas.” And God saw that it was good.

Then God said, “Let the land produce vegetation: seed-bearing plants and trees on the land that bear fruit with seed in it, according to their various kinds.” And it was so. The land produced vegetation: plants bearing seed according to their kinds and trees bearing fruit with seed in it according to their kinds. And God saw that it was good. And there was evening, and there was morning—the third day.

And God said, “Let there be lights in the expanse of the sky to separate the day from the night, and let them serve as signs to mark seasons and days and years, and let them be lights in the expanse of the sky to give light on the earth.” And it was so. God made two great lights-the greater light to govern the day and the lesser light to govern the night. He also made the stars. God set them in the expanse of the sky to give light on the earth, to govern the day and the night, and to separate light from darkness. And God saw that it was good. And there was evening, and there was morning—the fourth day.

And God said, “Let the water teem with living creatures, and let birds fly above the earth across the expanse of the sky.” So God created the great creatures of the sea and every living and moving thing with which the water teems, according to their kinds, and every winged bird according to its kind. And God saw that it was good. God blessed them and said, “Be fruitful and increase in number and fill the water in the seas, and let the birds increase on the earth.” And there was evening, and there was morning—the fifth day.

And God said, “Let the land produce living creatures according to their kinds: livestock, creatures that move along the ground, and wild animals, each according to its kind.” And it was so. God made the wild animals according to their kinds, the livestock according to their kinds, and all the creatures that move along the ground according to their kinds. And God saw that it was good.

Then God said, “Let us make man in our image, in our likeness, and let them rule over the fish of the sea and the birds of the air, over the livestock, over all the earth, and over all the creatures that move along the ground.” So God created man in his own image, in the image of God he created him; male and female he created them. God blessed them and said to them, “Be fruitful and increase in number; fill the earth and subdue it. Rule over the fish of the sea and the birds of the air and over every living creature that moves on the ground.” Then God said, “I give you every seed-bearing plant on the face of the whole earth and every tree that has fruit with seed in it. They will be yours for food. And to all the beasts of the earth and all the birds of the air and all the creatures that move on the ground—everything that has the breath of life in it—I give every green plant for food.” And it was so. God saw all that he had made, and it was very good. And there was evening, and there was morning—the sixth day.17

The opening line of Genesis is unique among creation stories. In this and only this story God brings the universe into existence seemingly out of nothing. God’s actions and the world’s response, emphasized in the quotation with different type, demarcate an underlying pattern. The clear declaration that the God of the early Hebrews has made all of creation stands apart from the pagan myths of the neighboring prehistoric cultures. This statement of God’s creative activity has always been understood as “out of nothing,” a creation of matter and energy and time itself. Unlike the pagan gods who worked with pre-existing materials, God spoke and creation occurred.

The repeated phrase “And God said” appears at the beginning of each creative event and is followed by creation’s obedience: “And it was so.” Capping these creative events is the declaration: “And God saw that it was good.” Although the sections vary in length and minor details, they follow the same pattern to reiterate that God created everything and made all things well.

The poetic structure of Genesis has been recognized for at least two millennia. As with much poetry, it has a repetitive form at several levels. On the first day God makes light and three days later he makes the heavenly lights, the sun and moon. On the second day God makes the sky and sea and three days later, the birds and fish to populate those realms. On the third day, God makes land and vegetation, the prerequisites for the land creatures and people that appear three days later on day 6. The first three days parallel the second three days: light and darkness/sun and moon, waters above and below/birds and fish, land and ocean/animals and humans. In the first three days the world is formed, while in the following three days the world is filled. The point of this unraveling symmetry is order. Each part of creation is linked together in a beautiful plan in which creative acts bring forth ecological diversity in an integrated, interdependent structure. Day seven is God’s crowning glory consistent with the veneration of many ancient cultures for the number 7.

Understanding Genesis 1

Numerous controversies have arisen from interpretations of Genesis. The two most prevalent stem from a literal reading of the poetic style: how did God make the universe and how long did this take? A literal reading of Genesis 1 as a scientific description of God’s action seems inappropriate given that the message was for a people living some time between 1500 and 500 BC. The early Hebrews’ knowledge of science was minimal, but they did have a keen understanding of how God expected them to live even if they did not always follow directions! As poetry, broad statements conveying order and place in creation could truthfully provide some insight into how God made the universe without describing the precise sequence or mechanism. An advantage of couching how the universe came into being through a poetic description is that the essence of God’s actions are captured in a medium that can be understood thousands of years later by modern, scientifically oriented cultures and still ring true. As poetry, Genesis is unlikely to contain specifics on the mechanism by which the universe came into being, but the language may allude to how long creation required.

Genesis implies that some creative acts were instantaneous: “‘Let there be light,’ and there was light.”18 Some commands imply a process of unspecified duration: “‘Let the water under the sky be gathered to one place, and let dry ground appear.’ And it was so.” 19 Other commands initiated a creative progression: “‘Let the land produce living creatures according to their kinds . . . .’ And it was so.” 20 The creative processes appear to require different amounts of time even though each creative event is bounded as taking a “day,” which differs from the typical use of “day” to refer to a twenty-four-hour period. Words such as day, evening, and morning are still used today in broad, non-precise ways. For example, in proposing to spend the day at the beach people do not plan on arriving at midnight and staying twenty-four hours.

A non-literal interpretation of the word “day” as used in Genesis overcomes analogous problems stemming from belief in a literal twenty-four-hour day, problems such as God’s work schedule. For example, if God created light instantaneously, what did he do for the rest of the day? Each creative event ends with “And there was evening and there was morning—the xth day.” Understanding this phrase as closing each creative event, rather than a literal description, alleviates the problem of a first “day” before the creation of sun and moon on “day” four. A poetic reading of each creative act views each day as bounding the creative periods, some short while others perhaps requiring eons.

Throughout the first half of the Bible the word “day” (yom) is loosely used in a variety of ways. Usually meaning a “day” of the week, the word can also mean “time,” a specific “period” or “era” or a season. A natural interpretation is to view the Genesis days as metaphors for geological ages. Each Genesis day broadly correlates with a time for each creative event whether requiring millions of years or milliseconds. Reading each of the Genesis days as periods of differing creative events overcomes difficulties with a literal interpretation while preserving the intent of the chapter; God created the world.

The description of creation in Genesis 1 ends with humanity. In Genesis 2 the focus of the story is on the first man, Adam, and his companion, Eve. There are no additional depictions of “creative days,” but rather events happening to humans with time being expressed in terms of a human life. Before the creation of mankind, Genesis is told from the perspective of God. After the creation of mankind, Genesis is told from the perspective of people. A reasonable interpretation of this difference is that time is described from God’s perspective during days of creation and from man’s perspective after creation. Einstein demonstrated that perspective means everything when considering time. The early Hebrews lived in step with the ebb and flow of the seasons, planting and harvesting according to weather rather than a set calendar. These people were less concerned with how long God worked each day and more focused on understanding God’s rule and role as ultimate creator.

Genesis 1 provides a clear declaration of God as the ultimate creator. As one of the grandest poems ever written, the meaning has been grasped by diverse cultures over thousands of years. Readers of Genesis predisposed to belief in God find the poem to ring true, squarely revealing God’s role despite the old-fashioned style. For others, Genesis may seem irrelevant; the Big Bang providing a better description of the universe’s beginning. The challenge in reading any creation story, biblical or scientific, lies in understanding the explanations of how and why.

Pre-biotic Evolution

Carl Sagan grandly paraphrases the opening lines of Genesis with an alternative creation story: “The universe is all there is, all there was, and all there ever will be.”21 While religion focuses on a creator who is “outside” the universe, science’s answers are from within the universe. Science’s creation stories rest on a wealth of internally consistent scientific data from a diverse array of different disciplines. From astronomy to zoology, the scientific disciplines are linked through a consistent multi-billion-year development of a primeval world into an intricate web of life. In contrast to the biblical focus on who creates, the scientific creation story provides details of how the universe was created and how long the process took.

Radioactive dating provides a reliable method for determining the age of the earth. The method relies on the presence of several heavy elements with “extra” neutrons within the atomic core. These neutrons are the nuclear glue holding the positively charged protons together. Sometimes the repulsion between protons in the nucleus of particularly large atoms causes the atom to split into two new elements having just slightly less overall mass than the parent atom. The mass difference is emitted as energy—the radioactive decay implicit in Einstein’s famous E=mc2. The main isotopes for geologically timing this process are uranium, lead, potassium, and argon. At the dawn of the earth a newly formed rock would contain uranium and lead in a specific ratio that subsequently changes because of the lead that is later produced through the radioactive decay of uranium to lead. Precisely monitoring the decay of uranium into lead over short time periods provides a rate that allows the uranium-to-lead ratio to be used to date when the rock was first formed. The process is akin to knowing how far a car goes on exactly one gallon of gas and using the mileage to estimate how far the car could go on a trip with a full tank of gas.

Radioactive dating is a method that affords the age of the earth with a remarkable degree of internal consistency. Scanning the periodic table of elements identifies many radioactive nuclei which decay at different rates. Of the thirty-four radioactive nuclei only twenty-three are found in detectable amounts in nature. This is consistent with the decay of all the short-lived nuclei since the earth’s formation. A few short-lived nuclei are produced by cosmic ray bombardment in the upper atmosphere, providing a continual production by a natural process. If these latter nuclei are eliminated from the list of persistent nuclei, then every nucleus with a half-life of less than eighty million years is missing. The earth must therefore be at least eighty million years old for the short-lived nuclei to decay out of existence. Using the radioactive dating technique with long-lived nuclei leads to the remarkable conclusion that planet earth formed about four billion years ago.

Fossils, glaciation, and the slow process of biological change hint at an ancient earth. Some religious groups believe that the earth was made in a week and is only a few thousand years old. Trying to harmonize these two beliefs is challenging. For example, if the universe were only 10,000 to 100,000 years old then what is the origin of the light from stars appearing to be billions of light years away? Did God make all the photons from the star to the earth sometime during his week’s work so that the star just seems to be billions of light years away? The scenario makes God out to be deceptive. The faithful and true character of God described in the Bible is more consistent with stars being billions of light years away from the earth.

The Water of Life

Life from non-living precursors is difficult to understand. How did life emerge from star dust and expand into every nook and cranny of earth? A series of events has been proposed to explain how the atmosphere of the early earth caused such gases as hydrogen, methane, carbon monoxide, carbon dioxide, ammonia, and nitrogen to trigger a series of condensations resulting in ever larger molecules. During the Hadean era, 3.5 to 4.5 billion years ago, the earth was pummeled by asteroids in a series of violent collisions. Each impact released energy to the earth’s surface, destroying even the most basic prebiotic molecules. Although these asteroids were primarily destructive, they’re speculated to have brought significant quantities of ice to the developing planet. More than any other molecule, water, perhaps brought to earth as ice, is critical for life.

Water is a marvelous substance with unique properties that make water essential for life. Water has one of the highest measures of surface tension, which allows droplets to cling to leaves and enables plants to draw water up from the roots. Water’s melting, boiling, and vaporization points are all much higher than those of related substances. Cooling shrinks and heating expands most materials, which is why bridges and buildings have expansion gaps. Water is anomalous in contracting until just above the freezing point where expansion occurs. The result is that ice floats on the surface of water, a property with dramatic consequences. If ice were heavier and denser than liquid water, as most solid phases are, then the ice would collect in the deepest recesses until cooling eventually turned all the lakes and the entire ocean into a solid mass. Life would be extremely difficult in a massive ice-block. Instead ice floats and, unlike water, is a poor heat conductor. Ice creates an insulating barrier between cold air above and the water below which therefore remains liquid.

Water can absorb more heat than almost any organic compound. Heat from the sun is absorbed by the oceans and lakes, providing a vast heat reservoir which moderates changes in temperature. Much energy is required to vaporize water, which makes water an excellent coolant by evaporation. Land animals make extensive use of this for cooling by sweating. An average person running for an hour would experience a fatal temperature increase of about 10 °C if they couldn’t sweat. The body’s five quarts of blood, largely water with a high heat absorption, counters the temperature increase and effectively cools the body through perspiration, allowing a modest overall rise in body temperature, but without frying the brain. Water has a host of unique properties: specific heat capacity, surface tension, and thermal conductivity properties, all of which conspire to make water a prerequisite for life.

Prebiotic Evolution on an Early Earth

Sometime close to 3.5 billion years ago, the earth’s surface cooled to less than 100 oC allowing water to condense into vast oceans. The oceans provided a haven for simple organic molecules that would have degraded at higher temperatures. Various forms of energy bathed the primitive earth—lightning, geothermal heat, atmospheric shock waves generated by meteoric impact, ultraviolet light from the sun, and others—driving reactions in the atmosphere and ocean to form a wide variety of simple organic molecules. Among the energy options, thunderstorms are proposed as a particularly important energy source for prebiotic chemical evolution because of the efficiency of the resulting shock waves in chemical synthesis. Shock waves surpass ultraviolet light by more than a million fold in efficiently producing amino acids, leading to the conclusion that shock waves may very well have been the principal energy source for prebiotic synthesis on the early earth.

In the upper zones of this primitive atmosphere there was no ozone layer to filter living things from lethal doses of ultraviolet light. Instead, ultraviolet light irradiated the gaseous atmosphere and formed simple organic molecules; formaldehyde, hydrogen cyanide, and ammonia among others. Conversion of these simple and sometimes toxic precursors into amino acids, the building blocks of life, seems remarkably unlikely and yet is supported by some equally remarkable experiments. The classic apparatus in the famous Miller-Urey experiment consisted of a small boiling flask containing water, a spark discharge chamber with tungsten electrodes, a condenser, and a water trap to collect the products and two or more of the following gases: methane, ethane, ammonia, nitrogen, water vapor, hydrogen, carbon monoxide, carbon dioxide, and hydrogen sulfide. Although the early earth is not thought to have had a boiling ocean, the boiling action of Miller’s apparatus provided a convenient means of circulating gases past the spark discharge. Perhaps even more important is the trap, which provides an efficient method for removing the mixture of products. About 2 percent of the resulting mass was in the form of amino acids. In the history of simulating prebiotic events, electrical discharge experiments have been repeated many times and consistently found to yield amino acids, the simplest building blocks required for protein synthesis.

On primordial earth, the diverse mixture of simple compounds formed in the atmosphere may have been washed down by rain into the oceans. Here life’s basic units may have accumulated along with the products of ocean reactions. Further reactions inevitably took place in this reservoir, and eventually the precursor chemicals reached the consistency of a “hot dilute soup.” Innumerable smaller bodies of water provided a mechanism for thickening the soup. None other than Charles Darwin first suggested a “shallow sun-warmed pond” as a place in which concentration occurred.22 Equally likely are lakes and shoreline lagoons, with alternate flooding and evaporation to provide a constant source of chemical ingredients and concentration to allow the molecules to come together and form larger biomolecules.

The hypothetical concentration is easily envisaged in small pools, perhaps screened from ultraviolet light by overhanging rock and situated in a warm environment as occurs naturally in countries with geothermal activity. This environment is commonly encountered in pools around Rotorua, New Zealand, and in Yellowstone National Park, although these places are inadequate for concentrating volatile substances such as aldehydes and HCN. Further concentration could occur by the accretion of organic compounds on sinking clay particles in shallow water basins. The surface of these clays can catalyze a variety of chemical reactions and could potentially condense these precursors into ever-larger molecules such as proteins and DNA.

Prebiotic evolution is not without problems. For example, carbon makes up almost 20 percent of the body’s mass and yet comprises only 0.03 percent of the earth’s crust. Similarly, DNA requires phosphorous in the form of phosphate, but this is one of the rarest light elements with a concentration in the earth’s crust of around 1000 ppm and about 1.5 ppb in the earth’s surface water. Phosphates are key constituents of not only nucleic acids but of many cell-signaling molecules. They also act as the storehouses for cells’ metabolic energy. However, phosphate readily forms insoluble complexes with several metal ions, particularly calcium, thought to be present in the early earth’s oceans. Access to soluble phosphates in the primitive ocean is problematic because of the prevalence of calcium and magnesium ions that readily form insoluble phosphate salts. How did such a relatively inaccessible essential element become incorporated into DNA?

The phosphorous problem and the success of the spark-discharge experiments encapsulate a fundamental principle in origin of life experiments. There is currently no direct demonstration by which simple organic molecules form selectively and then assemble into vast biopolymers having the functions found in living systems. Remarkable experiments demonstrate the viability of generating simple organic molecules, such as the amino acids from spark discharge experiments, and are suggestive of life-conferring processes. Many molecules found in living organisms are delicate, high energy species that are created by complex molecular machines, usually enzymes, that are without parallel. How these molecules formed in the absence of cellular machinery is one of the most puzzling questions for pre-biotic evolution.

Life’s Building Blocks

Ingenious experiments suggest mechanisms by which simple molecules coalesce into biomolecules. Scientists might not have created life, but the synthesis of life’s precursors has been clearly demonstrated in the lab. A corresponding condensation of life’s building blocks from an oceanic soup would be expected to be evident from rich seams of amino acids and DNA precursors—purines and pyrimidines—all over the earth in deep sediments of great age. No confirmation of an oceanic broth has been found.

Equally important to discovering how key building blocks formed is their rate of degradation. During the Hadean era, the energy required to form prebiotic molecules would also facilitate their degradation unless some sorting mechanism were available. Several atmospheric gases are polymerized or degraded under the conditions of early earth while others would have been quickly and irreversibly converted to organic salts in the alkaline ocean. Amino acids generated at high altitudes are estimated to require roughly three years to reach the ocean, during which they are degraded by UV radiation. In one estimate no more than 3 percent are expected to survive the passage to the ocean.

Most prebiotic molecules have a limited lifetime. One recent estimate for the four core monomeric building blocks of DNA suggests lifetimes ranging from nineteen days to twelve years. At temperatures near zero Celsius, the lifetime is extended to 17,000 years. Complex molecules tend to be fragile, leading some experts to speculate that life must have formed relatively quickly after earth cooled sufficiently. Distinguished origin-of-life researcher Leslie Orgel was overheard saying, “It would be a miracle if a strand of RNA ever appeared on the primitive earth.”23

Organic compounds degrade ever more quickly as the structures become more complex. In essence, macromolecular DNA has a much shorter “sell by” date than the small constituent nucleotide precursors. Although temperatures near freezing would give a better chance for the accumulation of the sufficient concentrations of organic compounds in the ocean, -21oC would be ideal for chemical evolution. If the early earth were some 20oC cooler than today because of less sunlight, there would be far fewer thunderstorms on the earth because thunderstorms are generated by warm, moist air coming into contact with cold, dry air. But thunderstorms are proposed as the most efficient energy source for generating prebiotic molecules. Origin of life research is plagued by this type of quandary; thunderstorms provide the right type of energy for condensing the basic building blocks of life, but the ideal conditions for preventing the degradation of the biopolymers, DNA, and amino acids, occurs at low temperatures where thunderstorms are extremely unlikely.

The difficulty in identifying an efficient mechanism for assembling prebiotic molecules has led some people to suggest that these molecules came from outer space. Meteorites, such as the Murchison meteorite in Australia, have been found to contain amino acids. The most predominant was the simplest amino acid glycine, comprising about 40 percent of the total amino acids in the case of the Murchison meteorite. The exact amount of amino acids arriving from meteorites is under dispute but has been estimated at 0.5 g each year during the time when life first appeared. Further complicating these estimates is the contamination of meteorites with amino acids already present in earth’s environment, particularly bacterially derived amino acids present in groundwater.

Life on earth is based on proteins and DNA. Forming these polymeric units involves assembling numerous precursors in a specific sequence in order to create functional biomolecules. Currently no broadly agreed sorting mechanism exists by which the correct sequence might be achieved. A similar puzzle exists at the atomic level where the formation of amino acids and nucleotides requires new molecules to form from atoms of low prevalence in the earth’s crust. Evidence from spark discharge experiments provides a tantalizing mechanism to explain the formation of amino acids and at the other end of the biological spectrum, all of life rests on proteins and DNA or RNA. The transition between these points remains a great mystery.

Divinely Guided Evolution?

Most scientists regard faith as something relegated to religion and are surprised to learn that science rests on several assumptions that amount to articles of faith. Belief forms the basis of scientific advances because, in proposing any hypothesis, scientists are effectively stating a belief about the world’s structure. The belief may be true or contain truth, and the refining nature of the scientific method leads to an understanding based on evidence that may be far from the original belief. Scientists operate on several axioms taken on faith:

1. Nature is Orderly. Nature has an underlying order shown in patterns and regularities that can be discovered. The orderly structure of nature is often thought to be self-evident; yet awareness of that order is relatively recent. Kepler (1571–1630) is often credited as identifying the underlying mathematical structure of the universe, which he believed stemmed from uncovering God’s purposeful design.24 John’s Gospel opens with a statement that explains the source of the purposeful order as stemming from God’s nature: “In the beginning was the Word,”25 the logos, the personal force, the understandable, ordered, rational principle on which all creation rests. In light of the logos infusing the world with rationality, including people, the validity of this understanding reflects the two-way, rational relationship intended between God and man. Einstein, in reflecting on the intelligibility of the universe and the ability to understand much of the complexity through science wrote: “God is subtle but malicious he is not.”26 In other words, the universe may be complex and contain unexpected patterns, but those are part of an orderly fundamental structure that can be understood. The world is not capricious but is a structured universe capable of being understood.

2. Nature is Uniform. The forces of nature are uniform throughout space and time. What happens in one laboratory in one country is reproducible under the same conditions anywhere around the world at any time.

3. Senses Perceive Reality. Coupled with the underlying order of nature is the ability of the human intellect to detect patterns and understand the meaning of the information inherent in the patterns. Reliable data can be obtained from the human senses or their extensions. Scientific instruments are assumed to give consistently reliable information about the way the world is despite not being able to directly “see” the object being interrogated. No-one has actually seen an electron, though scientists all believe they exist. Sensing reality is critical in scientific discovery because all abstract scientific discoveries are made first in the mind and then tested. Most of Einstein’s work falls in this category precisely because many of his theories were counter-intuitive.

4. Simplicity. If two theories or explanations fit the data, the simpler is usually to be preferred. For example, Copernicus’s solar-centric system did not provide more accurate data than that of the Ptolemaic geo-centric system—the advance, recognized by mathematicians, was a simpler calculation. Similarly, the most famous scientific equation of all time, E=mc2, simply and elegantly summarizes an awesome, fundamental truth underlying the universe’s structure.

The axioms on which science rests are philosophical assumptions. Scientist’s faith in these assumptions leads some individuals to make statements that are actually philosophical assertions. Each episode of the television show Cosmos began with Carl Sagan intoning that “The Universe is all there is . . .”—clearly a belief statement.27

Science cannot tell us why the universe is understandable or why the patterns in nature are so easily comprehended. Scientists simply make these assumptions, consciously or unconsciously, because they are so fruitful. Why people have brains capable of understanding remarkably intricate features from quantum theory to cosmology when these intellectually demanding areas have little immediate biological survival value is perplexing. From a religious perspective, the attributes of intelligence, power, and understanding are a natural consequence of people being made in God’s image.

The Origin of Information

Prebiotic evolution assumes a key role of chance, in the sense of a random occurrence, to provide the right chemicals for the transition from non-living components to the first living organism. Direct laboratory simulations of conditions on an early earth must address the problem inherent in trying to reproduce a process that apparently took millions of years. Detecting chance events with small probabilities requires a long time. A scientific approach to shorten the time requires an intentional, rational experiment to replicate the “chance” events that might have produced living organisms from non-living components. Usually, experiments with low probabilities are performed under intense conditions with greater frequency to improve the chance of a favorable outcome. Experimental design involves selecting pure chemicals that are subjected to geologically plausible conditions of energy input (heat, electric discharge) and environment (temperature, concentration, and pH). Successful experiments generate biologically significant molecules whereas unsuccessful experiments are refined and repeated until they are successful. This repeated give and take constitutes a necessary input of information from the experimentalist and a sorting of the output to find what is experimentally relevant.

Experimentally, the sorting is provided in the analysis of the reaction mixture. Most reactions generate a mixture of products from which one or two potential precursors are carefully identified and separated. Any intervention represents an input of information. Which products are significant? This depends on what you’re looking for, in other words, the experimental design has a specific type of product in mind for selection. This is like going to the beach and collecting shiny shells from the morass of sand and dead sea-life left along the shoreline.

The sorting process imparts information through selecting for what is important. Evolutionary models often trace the sorting mechanism to the environment, an ecological niche in biology or crystals capable of absorbing biological molecules, for example. Complex biological environments allow information to flow between organisms, such as changes to an animal’s coloring to blend into the environment. In this sense biological evolution is a natural process that distills information from the environment and captures the information in the genetic code. More difficult to understand is the generation of information from simple environmental features, such as crystals, which are regular and repetitious but have minimal information content. In the beginning of earth’s development there were no obvious sources of complex information. The search is for a natural process capable of amplifying minimal information inherent in minerals into complex genetic information.

The difficulty inherent in disentangling the origin of information is illustrated in spark discharge experiments. Mixtures of amino acids are generated that differ in a very subtle spatial orientation. The spatial complexity stems from an unusual peculiarity of carbon: the orientation of the four bonds allows two molecules to be assembled together with exactly the same connectivity but different arrangements in space. Each carbon center is like a hand with projecting fingers, thumb, and forearm attachments. The carbon center can have a “left” and “right” handedness, each of which naturally interlocks only with another left or right. In biological systems, the carbons of each amino acid is comprised of only one “hand.” Proteins have very specific, and usually very long, sequences all with the same geometric sequence—all “lefties” in a sense. The resulting sequence imparts very specific molecular complexity, particularly near the active site of enzymes where changing just one amino acid out of hundreds can render the enzyme inactive. Spark discharge experiments generate an equal mixture of two mirror-image amino acids that are very difficult to separate because their physical and chemical properties, like melting and boiling points, are identical. Randomly incorporating amino acids of each mirror image series from a mixture also containing natural and non-natural amino acids generated in discharge experiments is not likely to lead to a functional protein.

For the chemical synthesis of proteins, all of the amino acids must have the same handedness in a very specific order. As an analogy, if a house (protein) were to be built from an array of a hundred Lego blocks comprised of twenty different colors (amino acids) then the chance of assembling only a red house would be one in 20100! The chance of randomly assembling a functional protein is roughly the same as finding one grain of sand in a desert many times the size of the Sahara.

One estimate for the probability of assembling a functional enzyme through random chance puts the odds at one chance in 1020. Getting the sequence right is vital because proteins serve extremely diverse biological functions. Some proteins act as enzymes, some act as ropes that anchor bone and tendons together, while others form rubber-like soft tissue that surrounds the major arteries. Random chance seems unlikely to explain the complexity required for assembling the large, “handed,” three-dimensional structures so prevalent in nature. Is this the hand of God?

Assembling a functional protein requires positioning the amino acids in a specific sequence that encodes information. Enzymes contain very specific sequences of amino acids that create three dimensional “biological machines” where the sequence codes information specific to each type of enzyme. The information cannot come from some underlying attraction between amino acids because otherwise only one amino acid sequence would result. The amino acid sequence is flexible, allowing different sequences to code for different three-dimensional structures having different functions. The information coded into a protein vastly exceeds the information content of the laws governing molecular attraction. The term “specified complexity” tries to capture the meaning within a piece of information, specified in the sense of requiring a description for a specific function and complex in being unlikely to occur through chance. In this sense quartz is complex because the molecules pack into the crystal lattice in a very specific orientation, but there is minimal specificity. DNA has a very specific nucleotide order and is complex in being unlikely to have arisen by chance; other chance nucleotide orderings are possible but would not be specified. The laws of molecular attraction lead to regular repeating structures with minimal information, as found in beautiful crystals like Pyrite or fool’s gold. Crystals contain one instruction repeated millions of times whereas proteins and DNA contain many different instructions depending on the one sequence specified out of the millions of possibilities.

Information is fundamental to the nature of the universe. As the universe expands there are increasing numbers of states that can potentially be adopted and so the potential for increasing information. Intelligent agents are able to distinguish whether potential states are random or contain information encoded through abstract symbolism. The ability to perform abstract thinking is the link between information and intelligence which forms the basis for mathematics, computing, and all forms of communication.

People’s experience is that information comes from intelligent beings. The “Search for Extra-Terrestrial Intelligence” (SETI) involves searching for radio signals with specific patterns that convey information. Life’s existence is predicated on a vast amount of information whose source remains unknown. For some, such as SETI staff, the inability to find other sentient beings simply spurs the search on to different corners of the universe. For religious believers, God is the source of the intelligence in the universe. Each individual makes a free choice, informed by experience and logic, in deciding where the universe’s information comes from.

Replication

The distinction between molecules and living organisms is the information contained in the minimum number of instructions for replication. How the first proteins formed is an unsolved issue in origin-of-life research. Proteins have the remarkable ability to assemble themselves into very specific three-dimensional shapes with exactly the right groups positioned to execute their catalytic function. A protein’s shape not only defines the enzymatic active site but is also changed by interactions with other cell components. Ligand binding changes the protein sufficiently to prevent enzymatic activity and effectively functions as a molecular switch, turning an enzyme on and off. The dual functionality of proteins to manipulate the cell’s atomic building blocks and to provide a feedback mechanism signaling the needs of the cell has been called the second secret of life.

The same replication and feedback loops plague the formation of the first functional RNA and DNA. Polynucleotide strands require linking together one specific geometrically complex sugar with one of four nucleotide bases. Mechanisms continue to be discovered for condensing the monomeric units into the polymers required in functional DNA, with some remarkable consequences. For example, clay particles can provide active surfaces that not only facilitate the monomer condensation but also protect nucleic acids from degradation by a variety of energy sources. Small RNA sequences chosen to be partially self-complementary can self-assemble with a high preference for one monomeric “hand,” providing some encouragement for the origin of RNA sequences having the same sense of handedness.

The same information requirement reoccurs in many of the biomolecules required in cells. Proteins, DNA, fats, and a myriad of cell components are built from smaller components, requiring assembly in very specific sequences for normal cell function. If DNA is the software storing the cell’s information then proteins are the hardware that perform the cell’s functions. Some RNA can catalyze the formation of proteins but the amino acids are not specified during this process in the same way in which cells read DNA and select amino acids for protein synthesis. The fundamental problem lies in achieving replication; DNA codes for RNA that directs protein synthesis that, in addition to acting as the catalytic cell workers, ultimately result in the assembly of DNA.

The Beginning of Life

Exactly what separates living and non-living organisms? Defining the transition from organic molecules to life is enormously difficult because living organisms exhibit such remarkable diversity of complexity. Is a virus “alive”? Is an egg alive immediately after the sperm penetrates the cell wall, or not until the fertilized egg divides? At what point do a group of cells become a baby? Even trying to define life is fraught with difficulties. NASA provides an encompassing definition of “life [as] a self-sustained chemical system capable of undergoing Darwinian evolution.”28

Following science’s effective method of reducing a problem to the smallest discrete component, scientists have focused on the simplest expression of life in unicellular organisms. Simple cells contain four key types of complex molecules: proteins, nucleic acids (DNA and RNA), sugars (polysaccharides), and lipids. Each of these biomolecules is a polymer with a specific cell function: proteins perform the cellular reactions, nucleic acids code for the organization and replication of the cell, sugars trigger recognition events, and lipids form the core component of cell membranes.

DNA is often grandly called “the blueprint for life.” But despite the remarkable code embedded within DNA’s structure, DNA does not come close to the NASA definition of life. Rather, DNA behaves like many other polymers with an overall molecular motion caused by individual vibrations of the constituent atoms. Over time individual DNA molecules will move and bind to various receptors. However, the binding and recognition stems from the attraction between specific types of atoms rather than the inherent “mind” of DNA. The search for the beginning of life must, therefore, look not to smaller atomic entities but to larger structures of which DNA occupies just one critical role among many.

DNA contains an incredible amount of information. Tightly stuffed into cells, DNA would stretch to about 6 feet if drawn out from a human cell and unwound. Virtually all living organisms use DNA for storing the biological code; the chemical composition of the double helix varies between individuals and species but is universal for life on earth. How DNA came to be on earth 3.5 billion years ago is not known, but the common sequences between very diverse organisms provide an independent witness for DNA being crucial in life’s beginning.

Living Cells

Scientists have sought to find the key components of life from the earliest studies of biology and chemistry. Historically, people believed that there was a “life force” inherent in living systems that was not present in inorganic materials such as rocks and minerals. Few people believe in a vital life force any more, but, at the same time, the essential ingredients for life to appear and reproduce have also not yet been found.

Protocells represent the link between the synthesis of macromolecules and the appearance of the first living cells. Encapsulating all of the cellular components into an organized protocell is the biological equivalent of a quantum jump in understanding. The centrality of living cells has stimulated much research on the transition from cellular components to the formation of life. No other machine is known to completely assemble itself, creating one of the most daunting challenges in biochemistry. Self-replication in artificial systems is contingent on understanding this self-assembly. Understanding the evolutionary transition to replicating cells offers the potential to understand what life really is.

Cells are the central monomeric unit on which all life is based. Cells use close to a million different components and processes allowing them to function internally, to move, to signal to and find other cells, and to coalesce into multi-cellular organisms. Cells are truly remarkable nanoscale manipulators. Viewing cells gives the impression of a factory running by remote control because cells contain an enormous number of feedback loops to ensure that the right components are present in the cell. From an evolutionary perspective, the first cells would have a much simpler number of components that were later able to add additional levels of complexity.

A lipid-based cell wall provides a robust compartment capable of recognizing and excluding foreign invaders while providing a safe passage for cell metabolites. Localized within the cell are smaller entities that provide the energy for the cell (mitochondria) to synthesize proteins (Golgi), and form a central cognitive system (nucleolus). Efforts to mimic simple cells have identified reactions that can be performed inside cell walls, although these are controlled by the inherent reactivity of the chemicals rather than by a central cognitive system. Complementing this build-it-yourself strategy is the construction of artificial cells by inserting a minimal set of enzymes, nucleic acids, and cell metabolites to bring the cell to life. Simple processing by strings of RNA is possible but a great divide exists between simple chemical reactions and a cell capable of the three defining characteristics; metabolism, self-reproduction, and evolution. At the heart of the dilemma is the paradox of life: the cell components, the membrane proteins, RNA, and DNA are all interdependent. The cell wall and membrane encapsulate these key molecules in a safe environment which in turn requires proteins, DNA, and RNA for their synthesis. How cells became self-replicating is one of the most incomprehensible processes in biology.

An enormous gulf exists between simple and artificial cells and the simplest cellular organism. Genetic experiments aimed at determining how many genes are required in the simplest cell indicate that about 250 genes are minimally required for cell function. For a simple bacterium the genome consists of around 106 nucleotides, representing one DNA sequence out of a possible 102.4 million. The chance of randomly forming the genome is vanishingly small. Once the construction of the first living cell through synthetic assembly is achieved, if the endeavor is even possible, this will only provide a shadowy, though monumental, contribution to understanding the origin of life.

Perhaps the most striking aspect of the evolution of life on the earth is that it happened so fast. Scientists have suggested that life may be almost as old as the earth with an origin that may have virtually coincided with the birth of the planet. As an example, the population of organic walled microstructures from the Swaziland System, South Africa, found in 1977, was identified as the morphological remains of primitive prokaryotes. The rocks were dated as 3.4 billion years old, relatively close to the age of earth at 4.5 billion years. Despite dramatic advances in molecular biology, there is still no agreement in how life first began. Where and how life began is one of science’s great mysteries. Guesses range from life being a spectacularly successful accident to being the expected outcome of a universe primed for life.

Living cells are the most complex small systems in the universe. Specialized molecules work in concert, seamlessly conveying messages to ensure that the cell performs exactly the right function within the living organism. Most perplexing is the lack of an intelligent agent controlling the cell; life is sustained and replicated by individual organisms themselves. How the first single-celled organisms came into being is a puzzle which science has been trying to unravel. At the root of the problem is a philosophical issue: from where did life’s instructed complexity come? Organisms literally have a life of their own.

Information has to come from somewhere. DNA is full of information for protein synthesis, some of which forms the machinery to make and repair DNA. Random mutation can give rise to new sequences of potential information, requiring some screening process to weed out the beneficial mutations. That screening process is again another information source. Where did all the information come from in the beginning, and how did the protein-DNA symbiosis come into being? DNA is the cell’s software which delivers the message for protein synthesis on the cell’s main-frame. The origin of this information-rich system is currently unknown. Perhaps the information was primed into the universe from the beginning, although how this was done remains highly speculative.

The classic view of life’s origin is through a series of key events, each building on prior levels of complexity. Empty vesicles, like oil droplets, encapsulated primitive biomolecules whose chemistry powered the cell’s energy needs. During the progressive development, the enzymatic production of DNA was adopted, improved, and became an intimate part of cellular programming. The origin of many key steps in the development of life is as yet unidentified. Some argue that science will eventually be able to discover exactly how self-replicating, complex organisms first came into being. Others argue that life is too complex to understand completely and that while dramatic advances will continue, understanding life’s origin will always be elusive. Both are philosophical speculations.

Conclusion

The origin of life requires what currently appears to be a remarkable series of coincidences. Living organisms require a series of building blocks of ever increasing size: amino acids, proteins, nucleotides, DNA, and genes. Once in place, these key cellular components must coalesce to form single-celled organisms that subsequently diverge to produce plants, animals, and ultimately the human race. Every key biological development requires a remarkable level of complexity that increases as the precursors are incorporated within ever larger structures.

Interpreting the results of origin-of-life experiments is complicated by the practical limitations of reproducing conditions of early earth on a grand scale—no one wants a Big Bang in their back yard. Complicating the analysis of these intriguing experiments is identifying the origin of the information required to assemble complex biomolecules. Purely random events generate diversity that requires a sorting mechanism to retain the information present in the new molecular entities. At the current time the sorting mechanism is unknown and the rapid emergence of life so soon after earth became habitable remains an enigma.

Science has been remarkably successful in discovering how life works; for example, the discovery of DNA, mapping of the human genome, and cloning. Discovering the origin of life would make all prior Nobel Prize discoveries pale in comparison. However, from a philosophical perspective, there is no reason to believe that science should be able to discover the origin of life, nor, even if science discovered the origins of biological organisms, would this answer the philosophical questions this book raises. The driving force to search for answers to such difficult questions as the origin of life is largely because of science’s proven ability to discover new knowledge in the past and the likelihood that future benefits will accrue regardless of whether the original question is answered.

Prebiotic experiments demonstrate a remarkable synthesis of life’s building blocks despite gaps in current origin-of-life theory. For some, the experiments provide a compelling explanation for the spontaneous formation of life on earth while others believe such chance occurrences require some type of divine guidance. In the past, people have suggested specific developmental interventions, formation of the eye in particular. Time has harshly treated these God-of-the-gaps arguments. More recently, God’s input has been identified more within the unfolding of life on earth: God as the grand designer who continuously acts to bring the world into being. For religious people who experience God’s intervention in their lives, the question naturally arises as to why God would not similarly intervene in creation. The God of Genesis stresses the relationship of people to God as the key to understanding life. The figures of speech describing God’s attributes in human terms: making and speaking, conveying God as being personal and knowable, set the stage for an intimate relationship. God’s “hovering over the waters”29 makes his presence difficult to detect, and yet is consistent with God’s invitation to search for him in the world, leaving the interpretation of the evidence up to each individual.

Discussion Questions

1. The creation story in Genesis has often been interpreted as a literal six-day creation with the aim of creating men and women in relationship with God. How would the relationship between people and God be different if God were to create humans by a slow evolutionary process?

2. Is the idea of God consistent with an evolutionary process based on chance, waste, and suffering?

3. When a rose is picked from a rosebush, at what point is the rose “living” and “dead”?

4. A person who has just died leaves a body that no longer has life. What is the difference between the lifeless body and the virtually identical living person who inhabited the body just a few seconds or hours earlier? Is there a difference?

5. One proposal to explain the formation of high-energy biomolecules in the absence of cellular machinery is by a “frozen accident.” The idea is that an accidental occurrence generates a molecule that somehow becomes codified into the living process. What is the difference between the scientific postulate of a frozen accident and a religious assertion of divine intervention in the evolutionary process?

6. What guidelines should accompany the interpretation of lab experiments designed to mimic infrequent, long-term processes?

7. Amazing experiments are being performed to understand how life began, and with remarkable success. Should there be any limits to the forms of life that scientists can create? If so what would these be and why?

8. Richard Dawkins has written that “living organisms exist for the benefit of DNA rather than the other way round.”30 Does this statement ring true with the experience of life?

9. DNA is a remarkably complex molecule performing the intricate task of replicating cellular information. Is DNA designed? What are the indicators for or against DNA being designed?

Further reading for “The Origin of Life: Who or What Creates Life?”

1. Fazale Rana and Hugh Ross, Origins of Life: Biblical and Evolutionary Models Face Off. Colorado Springs: NavPress, 2004. Provides a comprehensive summary of recent advances in understanding the chemical and biological origin of life with extensive references to primary literature, reviews, and conference summaries. The material is covered from a Christian perspective, and requires an undergraduate education with familiarity in science.

2. Pier Luigi Luisi, The Emergence of Life: From Chemical Origins to Synthetic Biology. New York: Cambridge University Press, 2006. Covers the transition from prebiotic chemistry to synthetic biology with a clear focus on identifying the origin of life. Written for graduate students, the material is intensive but clear for those with an undergraduate degree in chemistry or biology.

3. Michael Denton, Nature’s Destiny: How the Laws of Biology Reveal Purpose in the Universe. New York: Free Press, 1998. Denton surveys a host of biological processes that point to the universe being finely tuned for the emergence of life. The fitness of a diverse set of chemical and biological processes is surveyed in an easily understandable level, and yet the material becomes somewhat overwhelming.

4. Christian de Duve, Vital Dust: Life as a Cosmic Imperative. New York: Basic, 1995. Biochemist and Nobel laureate de Duve surveys the rise of biomolecules through the primordial soup to the development of modern humans. De Duve does not invoke God or chance directly but seems to concede that because life is statistically unlikely the universe still seems programmed for life.

5. Paul Davies, The 5th Miracle. The Search for the Origin and Meaning of Life. New York: Touchstone, 1999. Science popularizer Paul Davies engages the most perplexing questions on the origin of life in an easy-to-read style. Davies weaves possible biological theories together with theories of life on Mars, Panspermia, and other planets that build on his earlier writings on cosmology. Davies is one of the finest, fairest writers with a poetic style who keeps the mystery of life and engages a few of life’s grand questions along the way.

6. Dean Overman, A Case Against Accident and Self-Organization. Rowman and Littlefield, 1997. Overman collects a vast array of information, largely from popular books, to argue that life is too complex to have arisen by chance. Overman presents the material in short sections comprising just a few pages and marshals the arguments like a lawyer, which he is.

15. Einstein, “Religion and Science.”

16. John Paul II, Letter of His Holiness John Paul II to Reverend George V. Coyne.

17. Gen 1:1–31

18. Gen 1:3

19. Gen 1:9

20. Gen 1:24

21. Sagan, Cosmos, 1.

22. Darwin, quoted in Ward and Brownlee, Rare Earth, 67.

23. Ross, Hidden Treasures in the Book of Job, 121.