Origin of life

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This article focuses on modern scientific research on the origin of life. For alternate uses, see origin of life (disambiguation).

Pre-Cambrian stromatolites in the Siyeh Formation, Glacier National Park. In 2002, William Schopf of UCLA published a controversial paper in the scientific journal Nature arguing that geological formations such as this possess 3.5 billion year old fossilized algae microbes. [1] If true, they would be the earliest known life on earth.

Research into the origin of life is a limited field of research despite its profound impact on biology and human understanding of the natural world. Progress in this field is generally slow and sporadic, though it still draws the attention of many due to the gravity of the question being investigated. A few facts give insight into the conditions in which life may have emerged, but the mechanisms by which non-life became life are still elusive.

For the observed evolution of life on earth, see the timeline of life.

History of the concept: abiogenesis

Main article: Abiogenesis

Research into the origin of life is the modern incarnation of the ancient concept of abiogenesis. Abiogenesis, in its most general sense, is the generation of life from non-living matter. The term is primarily used in the context of biology and the origin of life. Abiogenesis was long considered to be a very common occurrence until the Law of Biogenesis (omne vivum ex ovo or "all life from an egg") became firmly established in modern biology as a result of the work of Louis Pasteur.

Charles Darwin in a letter to J.D. Hooker of February 1st 1871, made the suggestion that life may have begun in a "warm little pond, with all sorts of ammonia and phosphoric salts, lights, heat, electricity, etc. present, that a protein compound was chemically formed ready to undergo still more complex changes, at the present day such matter would be instantly devoured or absorbed, which would not have been the case before living creatures were formed." Thus, it is the presence of life itself, operating in an oxygen rich atmosphere, itself a product of life, which prevents "spontaneous generation" from occurring on Earth today.

This modern definition of abiogenesis is concerned with the formation of the simplest forms of life from primordial chemicals, in an environment regarded as similar to that at the time shortly after the formation of the Earth. This is significantly different from the concept of Aristotelian abiogenesis, which postulated the formation of complex organisms. This article reviews different hypotheses for modern abiogenetic processes that are currently under debate.

Current models of the origin of life

There is no truly "standard" model of the origin of life, however most currently accepted models build in one way or another upon a number of discoveries concerning the origin of molecular and cellular components for life, which are listed in a rough order of postulated emergence:

1. Plausible pre-biotic conditions result in the creation of certain basic small molecules (monomers) of life, such as amino acids. This was demonstrated in the Urey-Miller experiment by Stanley L. Miller and Harold C. Urey in 1953.
2. Phospholipids (of an appropriate length) can spontaneously form lipid bilayers, one of the two basic components of a cell membrane.
3. The polymerization of nucleotides into random RNA molecules might have resulted in self-replicating ribozymes (RNA world hypothesis).
4. Selection pressures for catalytic efficiency and diversity result in ribozymes which catalyse peptidyl transfer (hence formation of small proteins), since oligopeptides complex with RNA to form better catalysts. Thus the first ribosome is born, and protein synthesis becomes more prevalent.
5. Proteins outcompete ribozymes in catalytic ability, and therefore become the dominant biopolymer. Nucleic acids are restricted to predominantly genomic use.

The origin (see Origin of organic molecules) of the basic biomolecules, while not settled, is less controversial than the significance and order of steps 2 and 3. The basic inorganic chemicals from which life was formed are methane (CH₄), ammonia (NH₃), water (H₂O), hydrogen sulfide (H₂S), carbon dioxide (CO₂), and phosphate (PO₄³⁺). As of 2004, no one has yet synthesized a "protocell" using basic components which has the necessary properties of life (the so-called "bottom-up-approach"). Without such a proof-of-principle, explanations have tended to be short on specifics. However, some researchers are working in this field, notably Jack Szostak at Harvard. Others have argued that a "top-down approach" is more feasible. One such approach attempted by Craig Venter and others at The Institute for Genomic Research involved engineering existing prokaryotic cells with progressively fewer genes, attempting to discern at which point the most minimal requirements for life were reached. The biologist John Desmond Bernal, in coining the term Biopoesis for this process suggested that there were a number of clearly defined "stages" that could be recognised in explaining the origin of life.

1. Stage: The origin of biological monomers
2. Stage: The origin of biological polymers
3. Stage: The evolution from molecules to cell

Bernal suggested that Darwinian evolution may have commenced early, some time between Stage 1 and 2.

Origin of organic molecules: Miller, Eigen and Wächtershäuser's theories

File:UreyMillerExperiment.jpg

The Miller-Urey experiment attempts to recreate the chemical conditions of the primitive Earth in the laboratory, and synthesized some of the building blocks of life.

The "Miller experiments" (including the original Miller–Urey experiment of 1953, by Harold Urey and his graduate student Stanley Miller) are performed under simulated conditions resembling those thought at the time to have existed shortly after Earth first accreted from the primordial solar nebula. The experiment used a highly reduced mixture of gases (methane, ammonia and hydrogen). However, it should be noted that the exact composition of the prebiotic atmosphere of earth is currently somewhat controversial. Other less reducing gases produce a lower yield and variety. It was once thought that appreciable amounts of molecular oxygen were present in the prebiotic atmosphere, which would have essentially prevented the formation of organic molecules; however, the current scientific consensus is that such was not the case.

The experiment showed that some of the basic organic monomers (such as amino acids) that form the building blocks of modern life can be formed spontaneously. Simple organic molecules are of course a long way from a fully functional self-replicating life form; however, in an environment with no pre-existing life these molecules may have accumulated and provided a rich environment for chemical evolution ("soup theory"). On the other hand, the spontaneous formation of complex polymers from abiotically generated monomers under these conditions is not at all a straightforward process. Further, according to Brooks and Shaw (1973), there is no evidence in the geological record that any soup existed.

"If there ever was a primitive soup, then we would expect to find at least somewhere on this planet either massive sediments containing enormous amounts of the various nitrogenous organic compounds, acids, purines, pyrimidines, and the like; or in much metamorphosed sediments we should find vast amounts of nitrogenous cokes. In fact no such materials have been found anywhere on earth."

Other sources of complex molecules have been postulated, including sources of extra-terrestrial stellar or interstellar origin. For example, from spectral analyses, organic molecules are known to be present in comets and meteorites. In 2004, a team detected traces of polycyclic aromatic hydrocarbons (PAH's) in a nebula, the most complex molecule, to that date, found in space.

It can be argued that the most crucial challenge unanswered by this theory is how the relatively simple organic building blocks polymerise and form more complex structures, interacting in consistent ways to form a protocell. For example, in an aqueous environment hydrolysis of oligomers/polymers into their constituent monomers would be favored over the condensation of individual monomers into polymers. Also, the Miller experiment produces many substances that would undergo cross-reactions with the amino acids or terminate the peptide chain.

In the early 1970s a major attack on the problem of the origin of life was organised by a team of scientists gathered around Manfred Eigen of the Max Planck Institute. They tried to examine the transient stages between the molecular chaos in a prebiotic soup and the transient stages of a self replicating hypercycle, between the molecular chaos in a prebiotic soup and simple macromolecular self-reproducing systems.

In a hypercycle, the information storing system (possibly RNA) produces an enzyme, which aids catalyse the formation of another information system, in sequence until the product of the last aids in the formation of the first information system. Mathematically treated, hypercycles could create quasispecies, which through natural selection entered into a form of Darwinian evolution. A boost to hypercycle theory was the discovery that RNA, in certain circumstances forms itself into ribozymes, a form of RNA enzyme.

Another possible answer to this polymerization conundrum was provided in 1980s by Günter Wächtershäuser, in his iron-sulfur world theory. In this theory, he postulated the evolution of (bio)chemical pathways as fundamentals of the evolution of life. Moreover, he presented a consistent system of tracing today's biochemistry back to ancestral reactions that provide alternative pathways to the synthesis of organic building blocks from simple gaseous compounds. In contrast to the classical Miller experiments, which depend on external sources of energy (e. g. simulated lightning or UV irradiation), "Wächtershäuser systems" come with a built-in source of energy, sulfides of iron and other minerals (e. g. pyrite). The energy released from redox reactions of these metal sulfides is not only available for the synthesis of organic molecules, but also for the formation of oligomers and polymers. It is therefore hypothesized that such systems may be able to evolve into autocatalytic sets of self-replicating, metabolically active entities that would predate the life forms known today. The experiment as performed, produced a relatively small yield of dipeptides (0.4–12.4%) and a smaller yield of tripeptides (0.003%) and the authors note that: "under these same conditions dipeptides hydrolysed rapidly." Another criticism of the result is that the experiment did not include any organomolecules that would most likely cross-react or chain-terminate. (Huber and Wächtershäuser, 1998)

The latest modification of the iron-sulfur-hypothesis has been provided by William Martin and Michael Russell in 2002. According to their scenario, the first cellular life forms may have evolved inside so-called black smokers at seafloor spreading zones in the deep sea. These structures consist of microscale caverns that are coated by thin membraneous metal sulfide walls. Therefore, these structures would solve several critical points of the "pure" Wächtershäuser systems at once:

1. the micro-caverns provide a means of concentrating newly synthesised molecules, thereby increasing the chance of forming oligomers;
2. the steep temperature gradients inside a black smoker allow for establishing "optimum zones" of partial reactions in different regions of the black smoker (e.g. monomer synthesis in the hotter, oligomerisation in the colder parts);
3. the flow of hydrothermal water through the structure provides a constant source of building blocks and energy (freshly precipitated metal sulfides);
4. the model allows for a succession of different steps of cellular evolution (prebiotic chemistry, monomer and oligomer synthesis, peptide and protein synthesis, RNA world, ribonucleoprotein assembly and DNA world) in a single structure, facilitating exchange between all developmental stages;
5. synthesis of lipids as a means of "closing" the cells against the environment is not necessary, until basically all cellular functions are developed.

This model locates the "last universal common ancestor" (LUCA) inside a black smoker, rather than assuming the existence of a free-living form of LUCA. The last evolutionary step would be the synthesis of a lipid membrane that finally allows the organisms to leave the microcavern system of the black smokers and start their independent lives. This postulated late acquisition of lipids is consistent with the presence of completely different types of membrane lipids in archaebacteria and eubacteria (plus eukaryotes) with highly similar cellular physiology of all life forms in most other aspects.

Another unsolved issue in chemical evolution is the origin of homochirality, i.e. all monomers having the same "handedness" (amino acids being left handed, and nucleic acid sugars being right handed). Homochirality is essential for the formation of functional ribozymes (and probably proteins too). The origin of homochirality might simply be explained by an initial asymmetry by chance followed by common descent. Work performed in 2003 by scientists at Purdue identified the amino acid serine as being a probable root cause of organic molecules' homochirality. Serine forms particularly strong bonds with amino acids of the same chirality, resulting in a cluster of eight molecules that must be all right-handed or left-handed. This property stands in contrast with other amino acids which are able to form weak bonds with amino acids of opposite chirality. Although the mystery of why left-handed serine became dominant is still unsolved, this result suggests an answer to the question of chiral transmission: how organic molecules of one chirality maintain dominance once asymmetry is established.

From organic molecules to protocells

The question "How do simple organic molecules form a protocell?" is largely unanswered. However, there are many different hypotheses regarding the path that might have been taken. Some of these postulate the early appearance of nucleic acids ("genes-first") whereas others postulate the evolution of biochemical reactions and pathways first ("metabolism-first"). Recently, trends are emerging to create hybrid models that combine aspects of both.

"Genes first" models: the RNA world

Main article: RNA world hypothesis

The RNA world hypothesis, for example, suggests that relatively short RNA molecules could have spontaneously formed that were capable of catalyzing their own continuing replication. Early cell membranes could have formed spontaneously from proteinoids, protein-like molecules that are produced when amino acid solutions are heated. Other possibilities include systems of chemical reactions taking place within clay substrates or on the surface of pyrite rocks. At this time however, these various hypotheses have incomplete evidence supporting them. Many of them can be simulated and tested in the lab, but a lack of undisturbed sedimentary rock from that early in Earth's history leaves few opportunities to determine what may have actually happened in reality. At this time however, no prebiotically plausible experiment has confirmed this assumption. Further, recent experiments suggest that the original estimates of the size of an RNA molecule capable of self-replication were most probably vast underestimates. Worse, RNA itself does not appear to be a prebiotically plausible molecule; therefore, more-modern forms of the RNA World theory propose that a simpler molecule was capable of self-replication (that other "World" then evolved over time to produce the RNA World).

"Metabolism first" models: iron-sulfur world and others

Several models reject the idea of the self-replication of a "naked-gene" and postulate the emergence of a primitive metabolism which could provide an environment for the later emergence of RNA replication. One of the earliest incarnations of this idea was put forward in 1924 with Alexander Oparin's notion of primitive self-replicating vesicles which predated the discovery of the structure of DNA. More recent variants in the 1980s and 1990s include Günter Wächtershäuser's iron-sulfur world theory and models introduced by Christian de Duve based on the chemistry of thioesters. More abstract and theoretical arguments for the plausibility of the emergence of metabolism without the presence of genes include a mathematical model introduced by Freeman Dyson in the early 1980s, and Stuart Kauffman's notion of collectively autocatalytic sets discussed later in that decade.

However, the idea that a closed metabolic cycle, such as the reductive citric acid cycle proposed by Günter Wächtershäuser, could form spontaneously remains unsupported. Further, according to Leslie Orgel, a leader in origin-of-life studies for the past several decades, there is reason to believe the assertion will remain so. In an article entitled "Self-Organizing Biochemical Cycles" (PNAS, vol. 97, no. 23, November 7 2000, p12503-12507), Orgel summarizes his analysis of the proposal by stating, "There is at present no reason to expect that multistep cycles such as the reductive citric acid cycle will self-organize on the surface of FeS/FeS2 or some other mineral."

The Bubble Theory

Another theory holds that the turbulent shores of the ancient coastal waters may have served as a mammoth laboratory, aiding in the countless experiments necessary to bring about the first cell. Waves breaking on the shore create a delicate foam composed of bubbles. Winds sweeping across the ocean have a tendancy to drive things to shore, much like driftwood collecting on the beach. It is possible that organic molecules were concentrated on the shorelines in much the same way. Shallow coastal waters also tend to be warmer, further concentrating the molecules through evaporation. While bubbles comprised of mostly water burst quickly, oily bubbles happen to be much more stable, lending more time to the particular bubble to perform these crucial experiments.

The phospholipid is a good example of an oily compound believed to be prevalent in the prebiotic seas. Because phospholipids contain a hydrophilic head on one end, and a hydrophobic tail on the other, they have the tendency to spontaneously form lipid membranes in water. A lipid monolayer bubble can only contain oil, and is therefore not conducive to harbouring water-soluble organic molecules. On the other hand, a lipid bilayer bubble can contain water, and was a likely precursor to the modern cell membrane. If a protein came along that increased the integrity of its parent bubble, then that bubble had an advantage, and was placed at the top of the natural selection waiting list. Primitive reproduction can be envisioned when the bubbles burst, releasing the results of the experiment into the surrounding medium. Once enough of the 'right stuff' was released into the medium, the development of the first prokaryotes, eukaryotes, and multi-celluar organisms could be acheived. This theory is expanded upon in the book, "The Cell: Evolution of the First Organism" by Joseph Panno Ph.D.

Hybrid models

A growing realization of the inadequacy of either pure "genes-first" or "metabolism-first" models is leading the trend towards models that incorporate aspects of each.

Other models

Clay theory of the origin of life

A hypothesis for the origin of life based on clay was forwarded by Dr A. Graham Cairns-Smith of Glasgow University in 1985 and adopted as a plausible illustration by just a handful of other scientists (including Richard Dawkins). Clay theory postulates complex organic molecules arising gradually on a pre-existing, non-organic replication platform - silicate crystals in solution. Complexity in companion molecules developed as a function of selection pressures on types of clay crystal is then exapted to serve the replication of organic molecules independently of their silicate "launch stage".

Cairns-Smith is a staunch critic of other models of chemical evolution (see Genetic Takeover: And the Mineral Origins of Life ISBN 0-52123-312-7). However, he admits, that like many models of the origin of life, his own also has its shortcomings (Horgan 1991).

"Deep-hot biosphere" model of Gold

A controversial theory put forward by Thomas Gold in the 1990s has life first developing not on the surface of the earth, but several kilometers below the surface. It is now known that microbial life is plentiful up to five kilometers below the earth's surface in the form of archaea, which are generally considered to have originated around the same time or earlier than bacteria, most of which live on the surface including the oceans. It is claimed that discovery of microbial life below the surface of another body in our solar system would lend significant credence to this theory. He also noted that a trickle of food from a deep, unreachable, source promotes survival because life arising in a puddle of organic material is likely to consume all of its food and become extinct.

"Primitive" extraterrestrial life

An alternative to Earthly abiogenesis is the hypothesis that primitive life may have originally formed extraterrestrially (note that exogenesis is related to, but is not the same as the notion of panspermia). Organic compounds are relatively common in space, especially in the outer solar system where volatiles are not evaporated by solar heating. Comets are encrusted by outer layers of dark material, thought to be a tar-like substance composed of complex organic material formed from simple carbon compounds after reactions initiated mostly by irradiation by ultraviolet light. It is supposed that a rain of cometary material on the early Earth could have brought significant quantities of complex organic molecules, and that it is possible that primitive life itself may have formed in space was brought to the surface along with it. A related hypothesis holds that life may have formed first on early Mars, and been transported to Earth when crustal material was blasted off of Mars by asteroid and comet impacts to later fall to Earth's surface. Both of these hypotheses are even more difficult to find evidence for, and may have to wait for samples to be taken from comets and Mars for study, and neither of them actually answers the question of how life first originated, merely shifting it to another planet/comet.

Relevant fields

• Astrobiology is a field that may shed light on the nature of life in general, instead of just life as we know it on Earth, and may give clues as to how life originates.
• Complex systems

See also

• Category:Origin of life
• Anthropic principle
• Biogenesis
• Drake equation
• Fine-tuned universe
• Important publications in origin of life
• Panspermia
• Planetary habitability
• Universal common ancestor
• Zeolites

References

ISBN links support NWE through referral fees

• JW Schopf et al. (2002). Laser-Raman imagery of Earth's earliest fossils.. Nature 416: 73-76. PMID 11882894
• Horgan, J (1991). In the beginning. Scientific American 264: 100–109. (Cited on p. 108).
• Huber, C. and Wächterhäuser, G., (1998). Peptides by activation of amino acids with CO on (Ni,Fe)S surfaces: implications for the origin of life. Science 281: 670–672. (Cited on p. 108).
• Brooks, J. and Shaw, G., 1973. Origins and Development of Living Systems. Academic Press, London and New York, p. 359.
• Martin, W. and Russell M.J. (2002). On the origins of cells: a hypothesis for the evolutionary transitions from abiotic geochemistry to chemoautotrophic prokaryotes, and from prokaryotes to nucleated cells. Philosophical Transactions of the Royal Society: Biological sciences 358: 59-85..

External links

• Astrobiology and the origins of life
• "SELF-REPLICATION: Even peptides do it" by Stuart A. Kauffman
• Cairns Smith illustration of a possible solution using crystalline behaviors of clays
• Model of origin of life involving zeolite, press release for PNAS paper
• Possible Connections Between Interstellar Chemistry and the Origin of Life on the Earth
• Scientists Find Clues That Life Began in Deep Space — NASA Astrobiology Institute
• The Deep Hot Biosphere Theory (Thomas Gold)
• Self-organizing biochemical cycles — by Leslie Orgel
• Evolution wiki

de:Entstehung des Lebens es:Origen de la vida fr:Origines de la vie he:מוצא החיים nl:Oorsprong van het leven ja:生命の起源 pl:Pochodzenie życia

Adding content on origin believe as well, although could be another article

The term origin belief refers to stories and explanations which describe the beginnings of humanity, earth, life, and the universe (cosmogony). Origins beliefs commonly refer to creation myths — mytho-religious stories which explain the beginnings of the universe as a deliberate act of "creation" by a supreme being. "Origin belief" may be generalized to include non-religious claims and theories based in contemporary science or philosophy—the Theory of evolution and the Big Bang fall into this category.

As with any set of beliefs, opinions regarding the validity of particular origins beliefs differ —points of view on these subjects vary widely.

The term creation myth may be seen as offensive when used to describe stories which are still believed today, as the term myth suggests ideas which are absurd or fictional. These beliefs and stories need not be a literal account of actual events, but may express what are perceived to be truths at a deeper or more symbolic level. Author Daniel Quinn notes that in this sense creation myths need not be religious in nature, and they have secular forms in modern cultures.

Many creation beliefs share broadly similar themes. Common motifs include the fractionation of the things of the world from a primordial chaos; the separation of the mother and father gods; land emerging from an infinite and timeless ocean; and so on.

Some religious groups assert that creation beliefs should complement scientific accounts of the development of life and the cosmos. This assertion has proven highly controversial. For an account of this debate, see creation-evolution controversy.

Science-based beliefs

Science, strictly speaking, deals only with observable phenomena. Anything that cannot be observed (either directly or indirectly) is, by definition, not a subject of scientific investigation. Scientists look for patterns among observations, which give rise to hypotheses to be tested against further observations. If a hypothesis passes these tests, it is then called a scientific theory, which again is subject to amendment or rejection based on new observations.

The ability of scientists to analyse unique and non-recurring events in the distant past (such as the creation of the universe) is limited, because such events cannot be directly observed and are difficult to repeat experimentally. However, science may be able to measure some of the effects of such events (for instance, via the microwave echo of the big bang) and interpret these observations within a scientific framework. By extrapolating the current observed state of affairs into the past, scientists seek to construct an accurate picture of the past. Those who are strict adherents to philosophical naturalism believe that such is all that is possible to know. This is not a universally accepted idea by any means, and there are many who promote other paths to knowledge which are not characterised as scientific inquiry.

In scientific theories supported by the mainstream scientific community, the universe and life is described as developing through solely natural causes, and the progress of science is hoped to continue to improve the explanation of things and events in the past.

Creation science is a creationist effort to integrate science and Abrahamic faith by allowing for both supernatural causes of phenomena as generally described by creation according to Genesis and the application of the scientific method in interpreting observable phenomena. It is rejected as pseudoscience by the mainstream scientific community.

Accepted mainstream scientific theories

The Big Bang theory is the dominant cosmological theory about the early development and current shape of the universe. The ultimate origin of the preconditions for the universe is currently a subject of speculation, and some believe it is beyond the bounds of scientific inquiry. The solar nebula is considered the best planetary system formation model available for explaining the origin of the solar system. The Earth-moon system was formed out of this as described by the Giant impact theory.

The modern evolutionary synthesis is the dominant biological theory about the origin of human life on Earth. This combines Charles Darwin's theory of the evolution of species by natural selection with Gregor Mendel's theory of genetics as the basis for biological inheritance.

The origin of life itself on Earth is more contested. Scientific conjectures, hypotheses, and observations pertaining to this topic are detailed in the article on the origin of life.

It should be pointed out that the above scientific theories are not ex nihilo beliefs, that is they do not start from nothing. They provide no mechanism for the origin ex nihilo of energy or matter. In this respect they are unlike the Jewish, Christian, and Islamic beliefs which assert that the universe, Earth, and life originated in a unique creative act by God, or "scientific" speculations which propose an original cause of some other type. For a more precise understanding of modern science's concepts concerning "matter from vacuum" or "something from nothing" see virtual particle and vacuum energy.

Beliefs grounded in philosophical naturalism

Atomism is an ancient Greek philosophy supported by Democritus, Epicurus and Lucretius which held that events in the universe were not the consequence of any act by a Creator, but rather was the result of atoms moving about randomly. This philosophy was reformulated as determinism after the Enlightenment and still enjoys a following by some scientists, though the character of deterministic interactions in nature involving quantum mechanics is an outstanding question.

The Anthropic Principle and its more controversial derivative the Strong Anthropic Principle are explanations for the existence of humanity with respect to the conditions of the universe that we inhabit. The principle is used as a guide for some scientists to determine certain physical laws that have necessarily resulted in the existence of ourselves. In some sense, the Anthropic Principle is an empirical truism while the Strong Anthropic Principle is an idea that may defy falsification.

Deism was a popular belief of many scientists and philosophers of the post-enlightenment, including Newton, Leibnitz, and Thomas Jefferson that kept the formality of a creator, but allowed creation to function solely based on natural laws that were established at the time of creation. In this formulation, every interaction was completely deterministic.

The Many worlds interpretation of quantum mechanics and the idea of parallel universes are ways of resolving questions of causality and determinism in the framework of probabilistic interactions. In this speculative interpretation, the universe that we inhabit is one of many possible universes that all simultaneously exist, but are independent of each other, and each universe bifurcates with every quantum mechanical "observation".

Creation ex nihilo

Creation ex nihilo (Latin: out of nothing) is at odds with our everyday experiences, in that nothing spontaneously comes into (or vanishes from) existence but instead matter and energy merely change forms. However, quantum mechanics allows for energy to be spontaneously created from the vacuum as long as the Heisenberg Uncertainty Principle is not violated (usually, by the spontaneous annihilation of the created particles, e.g. the Lamb shift). This may give a means by which creation ex nihilo can be achieved, but nevertheless we are not currently able to explain creation ex nihilo, nor even to prove that it is required.

An explanation advanced by some theists is that God created the Universe out of nothing; some creationists hold also that life was created in something like its present state of variety, so that organisms were fully speciated from the beginning. While there are various attempts to square these ideas with available evidence and currently accepted theory, their explanatory utility, predictive power, and scientific standing are questioned by critics of creationism. Many scientists in the relevant fields, theist and otherwise, do not regard notions like divine power or divine will as playing genuine scientific roles in cosmology or biology.

The scientifically prevalent view is that life originated on Earth, although other views hold that organic compounds from comets may have been an important source of material for the appearance of life. The Miller-Urey experiment showed that amino acids could arise from a type of primitive environment. Nevertheless, while scientific research on abiogenesis is ongoing, there is no consensus on how life began.

Religious creation beliefs

Several religions have creation stories, some of which account for the existence and present form of the Universe by the act of creation by a supreme being or the Creator God. Most of these accounts depict one or several gods fashioning things out of themselves, or from pre-existing material (for example chaos or prakriti).

The scholastic traditions of Judaism, Christianity, and Islam for the most part speak of creation ex nihilo. This is typified, for example, by the assumption that the first verse of the Christian Bible ("In the beginning, God created the heavens and the earth") indicates the only self-existent entity is God with all other things deriving from God. 2 Maccabees 7:28 indicates that this philosophy may have been a common Jewish understanding of creation: "I beseech thee, my son, look upon the heaven and the earth, and all that is therein, and consider that God made them of things that were not ...". Similar to this is the language found in the Book of Hebrews, which states, "Through faith we understand that the worlds were framed by the word of God, so that things which are seen were not made of things which do appear". Some (notably Augustine of Hippo) also hold that God is altogether outside of time and that time exists only within the created universe.

However, in these traditions, the belief that God gave shape to pre-existing things was not unheard of, and that idea became more fully articulated especially under the influence of Greek philosophy. In both Judaism and Christianity, belief in creation "from nothing" began to dominate the traditions sometime in the second century C.E., in part as a reaction against classical philosophy. The following story from the Talmud illustrates this:

A philosopher said to R. Gamiliel: Your God was a great craftsman, but he found himself good materials which assisted him: Tohu wa-Bohu, and darkness, and wind, and water, and the primeval deep. Said R. Gamiliel to him: May the wind be blown out of that man! Each material is referred to as created. Tohu wa-Bohu: "I make peace and create evil"; darkness: "I form the light and create darkness"; water: "Praise him, ye heaven of heavens, and ye waters" — why? — "For he commanded, and they were created"; wind: "For, lo, He that formeth the mountains, and created the wind"; the primeval deep: "When there were no depths, I was brought forth". BR 1.9, Th-Alb:8

Departing from this tradition, some modern scholars have argued that these statements and all others are still susceptible to ambiguous interpretation, so that creation ex nihilo may not be clearly supported by ancient texts, including the Bible. They point out the similarities of the biblical account, to other ancient religious beliefs that the universe was created by God or the gods out of pre-existing matter, as opposed to "out of nothing". Some scholars see evidence that the biblical account, like other ancient religious views, presumes pre-existence of some kind of raw material, albeit without form: "Now the earth was formless and void, darkness was over the face of the deep, and the spirit of God hovered over the waters." God then fashions the disordered material, to create the world.

• Dictionary of the history of Ideas: Creation in Religion
• The Qur'an and Earth, an islamic perspective of creation.

Limits to the ontology of creation

While many scenarios are proposed by religion and science to identify 'first cause' and the origin of creation (ontology), there are some fundamental limits to the knowledge of humankind that present a barrier to finding any definitive answer.

Post-modern philosophy currently holds that there is nothing that one can know for certain. Kant put a good case to show that because we view the universe through the lens of the mind, which is 'shaped' by space, time, and the things embedded in space and time, it is not possible to see things-in-themselves (noumena) - the real objects that lie behind the subjective objects (phenomena) we recognise. If true, it is beyond the mind of humankind to perceive a condition that has no space or time. Many other philosophers, most recently Popper have all shown that there is precious little one can be sure of that would provide a starting point to determine the 'first cause' that led to creation.

Modern physics is an empirical science based on experiment and observation that characterizes how things happen through scientific theories and physical laws, but ultimately does not answer the question of 'why' things happen at the foundational (ontological) level. For example, the existence of the Big Bang is not predicated on a reason for its occurrence. What's more, the modern physics breaks down at the Planck time/Planck length, where both the influences of quantum mechanics and gravity are required to be combined in order to characterize the interactions that occur. As such, there is no model available that has been tested at this level, and so any attempt to theoretically probe beyond this regime in search of a more fundamental appreciation of the nature of the universe is hampered.

Religion has philosophy and oral testimony available to it to demonstrate a God or a separate "first cause" that called the universe into existence. As such it is dependent on faith in God or the specific "first cause" to which it ascribes.

Creation within various belief systems

Some creation beliefs are part of a named system of beliefs and are labeled as such below. Some creation beliefs seem to be better characterized according to time and/or place as they are part of a human culture in a time/place.

Babylonia

The Babylonian creation myth is described in Enûma Elish. It existed in various versions and copies, the oldest dating to at least 1700 B.C.E.

In the poem, the god Marduk arms himself and sets out to challenge the monster Tiamat. Marduk destroys Tiamat, cutting her into two halves which become the Earth and the sky. Later on, he also destroys Tiamat's husband, Kingu, and uses his blood to create mankind. (Reference: A. Leo Oppenheim, Ancient Mesopotamia.)

Buddhism

Buddhism does not posit an eternal self or soul. Neither does it posit or assume an absolute first cause of all existence, such as a Creator God in the Judeo-Christian-Islamic tradition. Furthermore, Buddhism rejects the idea of a single, special event being the beginning of all existence. The phrase "since beginningless time" is frequently used. The Big Bang may very well be the beginning of the current era in our local universe, but there is no reason to believe that it was anything other than just another link in the eternal chain of cause and effect. In summary, Buddhism rejects the whole idea of an identifiable origin of everything.

China

There are five major views of creation in China:

• The first, and most consistent historically, is that no myth exists. This is not to say there were none existing at all, only that there is no evidence showing an attempt to explain the world's origin.

• The second view is very indirect. It is merely based on a question of a dialog in an earlier reference. The idea in the question implies that the heavens and the earth separated from one another.

• The third view is the one perpetuated by Taoism by the nature of its philosophy. It appears "relatively" late in Chinese history. In it, Tao is described as the ultimate force behind the creation. With tao, nothingness gave rise to existence, existence gave rise to yin and yang, and yin and yang gave rise to everything. Due to the ambiguous nature of this myth, it could be compatible with the first myth (and therefore say nothing). But it could, like its antithesis, be explained in a way to better fit the modern scientific view of the creation of universe.

• The fourth view is the relatively late myth of Pangu. This was an explanation offered by Taoist Monks hundreds of years after LaoZi; probably around +0200 C.E. In this story, the universe begins as a cosmic egg. A god named Pangu, born inside the egg, broke it into two halves: The upper half became the sky, the lower half became the earth. As the god grew taller, the sky and the earth grew thicker and were separated further. Finally the god died and his body parts became different parts of the earth.

• The fifth view would be tribal accounts that vary widely and not necessarily connect to a system of belief.

Christianity

Main articles: Creation according to Genesis, Creationism

References to God in the New Testament vary, however, overall they demonstrate an incorporation of the first cause. It should be noted, however, that the Chrisitian conception of God, the holy trinity, is more complex. The following examples illustrate this:

Revelation 1:8 - I am the Alpha and the Omega, the beginning and the end... that which is, which has been, and that which is yet to come, Almighty God.

John 1:1-4 - In the beginning was the Word, and the Word was with God, and the Word was God. The same was in the beginning with God. All things were made by him; and without him was not any thing made that was made. In him was life; and the life was the light of men.

The Church of Jesus Christ of Latter-day Saints

Followers of The Church of Jesus Christ of Latter Day Saints believe that physical reality (space, matter and/or energy) is eternal, and therefore does not have an absolute origin. The Creator is an architect and organizer of pre-mortal matter and energy, who constructed the present universe out of the raw material.

Creek

The Creek believe that the world was originally entirely underwater. The only land was a hill, called Nunne Chaha, and on the hill was a house, wherein lived Esaugetuh Emissee ("master of breath"). He created humanity from the clay on the hill.

Egyptian

File:Nun.gif There were at least three separate cosmogenies in Egyptian mythology, corresponding to at least three separate groups of worshippers.

• The Ennead, in which Atum arose from the primordial waters (Neith), and masturbated to relieve his loneliness. His semen and breath became Tefnut (moisture) and Shu (dryness), respectively. From Shu and Tefnut, were born Geb (earth), and Nuit (sky), who were born in a state of permanent copulation. Shu separated them, and their children were Ausare (Osiris; death), Set (desert), Aset (Isis; life), and Nebet Het (Nephthys; fertile land). Osiris and Isis were a couple, as were Nepthys and Set.
• The Ogdoad, in which Ra arose, either in an egg, or a blue lotus, as a result of the creative interaction between the primordial forces of Nu/Naunet (water), Amun/Amunet (air), Kuk/Kauket (darkness), and Huh/Hauhet (eternity). Ra then created Hathor, his wife, with whom they had a son, Hor (Horus; in the form known as Horus the Elder), who was married to Isis. This cosmogeny also includes Anupu (Anubis) as lord of the dead, amongst others.
• The third group, for whom Ptah was eternal and everlasting, and he spake the world and all the gods into existence, in a similar manner to Judao-Christian belief about their concept of God.

Over time, the rival groups gradually merged, Ra and Atum were identified as the same god, making Atum's mysterious creation actually due to the Ogdoad, and Ra having the children Shu and Tefnut, etc. In consequence, Anubis was identified as a son of Osiris, as was Horus. Amun's role was later thought much greater, and for a time, he became chief god, although he eventually became considered a manifestation of Ra.

For a time, Ra and Horus were identified as one another, and when the Aten monotheism was unsuccessfully introduced, it was Ra-Horus who was thought of as the Aten, and the consequent cosmogony this inspired. Later, Osiris' cult became more popular, and he became the main god, being identified as a form of Ptah. Eventually, all the gods were thought of as aspects of Osiris, Isis, Horus, or Set (who was by now a villain), indeed, Horus and Osiris had started to become thought of as the same god. Ptah eventually was identified as Osiris.

Classical Greece

Plato, in his dialogue Timaeus, describes a creation myth involving a being called the demiurge.

Hesiod, in his Theogony, says that Chaos existed in the beginning, and then gave birth to Gaia (the Earth), Tartarus (the Underworld), Eros (desire), Nyx (the darkness of the night) and Erebus (the darkness of the Underworld). Gaia brought forth Ouranos, the starry sky, her equal, to cover her, the hills, and the fruitless deep of the Sea, Pontus, "without sweet union of love," out of her own self. But afterwards, Hesiod tells, she lay with Heaven and bore the World-Ocean Oceanus, Coeus and Crius and the Titans Hyperion and Iapetus, Theia and Rhea, Themis and Mnemosyne and Phoebe of the golden crown and lovely Tethys. "After them was born Cronos the wily, youngest and most terrible of her children, and he hated his lusty sire." Cronos, at Gaia's urging, castrates Ouranos. He marries Rhea who bears him Hestia, Demeter, Hera, Hades, Poseidon, and Zeus. Zeus and his brothers overthrow Cronos and the other Titans, then draw lots to determine what each of them will rule. Zeus draws land, Poseidon draws sea, and Hades draws death.

Hinduism

The Mahaa-Vishnu, into whom all the innumerable universes enter and from whom they come forth again simply by His breathing process, is a plenary expansion of Krishna. Therefore I worship Govinda, Krishna, the cause of all causes. (Brahma-samhitaa 5.48)

In Hindu philosophy, the existence of the universe is governed by the Trimurti of Brahma (the Creator), Vishnu (the Sustainer) and Shiva (the Destroyer). The sequence of Avatars of Vishnu- the Dasavatara (Sanskrit: Dasa—ten,Avatara—incarnation) is generally accepted by most Hindus today as correlating well with Darwin's theory of evolution, the first Avatar generating from the environment of water.

Hindus thus do not see much conflict between creation and evolution. An additional reason for this could also be the Hindu concept of cyclic time, such as yugas, or days of Brahma in some four billion year cycles (unlike the concept of linear time in many other religions). In fact, time is represented as Kaala Chakra — the Wheel of Time.

In Hinduism, nature and all of God's creations are manifestations of Him. He is within and without his creations, pervading the entire universe and also observing it externally. Hence all animals and humans have a divine element in them that is covered by the ignorance and illusions of material or profane existence.

Hopi

The Elders say that the first Hopi had chosen to live in the barren desert so that they would always need to pray for rain. Thus, they would not lose faith in their ceremonies, which maintain their bond with the Mother Nature and Creator. They said that the True Hopi people represent the Red race through the authority vested in them by the Creator, Maasaw.

Hmong

According to Hmong tradition, a long time ago the rivers and ocean covered the Earth. A brother and sister were locked in a yellow wooden drum. The Sky People looked out and saw the Earth. Everything was dead. Only a yellow wooden drum was left on the water.

"Punch holes in the Earth so the water will drain away," said the King above the Sky.

The water went down. Finally, the drum bumped against the ground. The brother and sister came out of the drum and looked around. Everything was dead.

"Where are the people?" asked the sister.

But the brother had an idea. "All the people on Earth are gone. Marry me, we can have children."

"I can't marry you, we are brother and sister."

But he asked her again and again and she said, "No."

Finally the brother said, "Let's carry the grindstones up the hill and roll them into the valley. If the stones land on top of each other, then you shall marry me."

The sister rolled her stone and then, as soon as the brother rolled his stone he ran as fast as he could down the hill and stacked the stones on top of each other.

When the sister saw the stones she cried. Finally she said, "I will marry you, because it was meant to be."

A year later the wife gave birth to a baby, but the baby was not a real baby. It had no arms or legs. It was just round like a pumpkin. The husband cut it up and threw the pieces away. One piece fell on the garden and it became the "Vang" clan because "Vang" sounds like the word for "garden" in Hmong. One piece fell on the goat house. Some pieces fell on the leaves and grass and they became the other Hmong clans. The Nhia, Mhoua, Pao, Ho, Xiong, Vue, and so on.

The next morning the village was full of houses. Everyone came to the husband and wife and said, "Mother and father, come have breakfast with us."

The husband said to his wife, "I asked you to marry me because all the people on Earth were dead. Now these people are our family — our sons and daughters."

Inca

The Incan account of creation is known based on what was recorded by priests, from the iconography on Incan pottery and architecture, and the myths and legends which survived amongst the native peoples. According to these accounts, in the most ancient of times the earth was covered in darkness. Then, out of a lake called Collasuyu (modern Titicaca), the god Con Tiqui Viracocha emerged, bringing some human beings with him. Then Con Tiqui created the sun (Inti), the moon and the stars to light the world. It is from Inti that the Sapa Inca, emperor of Tawantinsuyu, is descended. Out of great rocks Con Tiqui fashioned more human beings, including women who were already pregnant. Then he sent these people off into every comer of the world. He kept a male and female with him at Cuzco, the "navel of the world."

Con, the Creator; was in the form of a man without bones. He filled the earth with good things to supply the needs of the first humans. The people, however, forgot Con's goodness to them and rebelled. So he punished them by stopping the rainfall. The miserable people were forced to work hard, drawing what little water they could find from stinking, drying riverbeds. Then a new god, Pachacamac, came and drove Con out, changing his people into monkeys. Pachachamac then took earth and made the ancestors of human beings..

The founder of the first dynasty of the kingdom of Cuzco was Manco Capac. In one legend he was brought up from the depths of Lake Titicaca by the sun god Inti. In another he was the son of Tici Viracocha. However commoners were not allowed to speak the name of Viracocha, which is possibly an explanation for the need for two foundation legends.

In one myth Manco Capac was the brother of Pachacamac, both were sons of the sun god Inti who is also known as Apu Punchau. Manco Capac himself was worshiped as a fire and sun god. According to the Inti legend, Manco Capac and his siblings were sent up to the earth by the sun god and emerged from the cave of Pacaritambo carrying a golden staff, called ‘tapac-yauri’. They were instructed to create a Temple of the Sun in the spot where the staff sank into the earth, they traveled to Cusco via underground caves, and built a temple in honor of the sun god Inti, their father. During the journey to Cuzco, one of Manco’s brothers, and possibly one of his sisters, were turned to stone (huaca). In another version of this legend, instead of emerging from a cave in Cuzco, the siblings instead emerged from the waters of Lake Titicaca.

In the Tici Virachocha legend, Manco Capac was the son of Tici Viracocha of Pacari-Tampu (today Pacaritambo, 25 km south of Cuzco). He and his brothers (Ayar Anca, Ayar Cachi and Ayar Uchu) and sisters (Mama Ocllo, Mama Huaco, Mama Raua and Mama Cura) lived near Cuzco at Paccari-Tampu, and united their people and ten ayllu they encountered in their travels to conquer the tribes of the Cuzco Valley. This legend also incorporates the golden staff, which is thought to have been given to Manco Capac by his father. Accounts vary, but according to some versions of the legend, the young Manco jealously betrayed his older brothers, killed them, and became the sole ruler of Cuzco.

Islam

In Islam all creation is attributed to Allah (the proper name for God in Arabic), the one and only God for Muslims. He is clearly identified as the "first cause" at numerous places in the Qur'an. Three instances follow:

(13:16) … Say: Allah is the Creator of all things, and He is the One, the Supreme

(57:3) … He is the First and the Last and the Manifest and the Hidden, and He is Knower of all things

(112:1) … Say: He, Allah, is One

(112:2) … Allah is He on Whom all depend

Referring to the first cause argument the Qur'an addresses the non-believers:

(52:35) … Or were they created without a (creative) agency? Or are they the creators?

(52:36) … Or did they create the heavens and the earth? Nay, they are sure of nothing.

Japan

The god Izanagi and goddess Izanami churned the ocean with a spear to make a small island of curdled salt. Two deities went down to the island, mixed there, and bore main islands, deities, and forefathers of Japan. See Japanese mythology#Creation of the world.

Judaism

Main articles: Creation according to Genesis, Creationism

The notion of "Tzimtzum", or God's retraction to make way for space and time, is a core element to the Jewish approach to the First Cause notion, as explored by Rabbi Moses Maimonides.

Maya

The Maya of Mesoamerica creation story is recounted in the book "Popol Vuh". In the beginning there is only sky and sea, personified as a trinity of gods called Heart-of-Sky. They decide that they want someone to praise them. They begin by saying "Earth", which appears on demand from the sea. This is followed by mountains and trees, and Heart-of-Sky establish that "our work is going well". Next for creation are the creatures of the forest: birds, deer, jaguars and snakes. They are told to multiply and scatter, and then to speak and "pray to us". But the animals just squawk and howl. They are consequently humbled and will become servants to whoever will worship Heart-of-Sky. So Heart-of-Sky try to make some more respectful creatures from mud. But the results are not great, and they allow the new race to be washed away. They call upon their grandparents, who suggest wood as an appropriate medium. But the wooden people are just mindless robots, so Heart-of Sky set about the destruction of this new race by means of a rain-storm. This causes the animals to turn against the wooden people; even their pots and querns rebel, and crush the peoples' faces. The wooden people escape to the forests and are turned into monkeys. Heart-of-Sky then make yet another attempt at creating a suitably respectful race, and finally succeed by fashioning humans out of maize-corn dough.

Maori

The Maori creation myth tells how heaven and earth were once joined as Ranginui, the Sky Father, and Papatuanuku, the Earth Mother, lay together in a tight embrace. They had many children who lived in the darkness between them. The children wished to live in the light and so separated their unwilling parents. Ranginui and Papatuanuku continue to grieve for each other to this day. Rangi's tears fall as rain towards Papatuanuku to show how much he loves her. When mist rises from the forests, these are Papa's sighs as the warmth of her body yearns for him and continues to nurture mankind.

Navajo

In the beginning there were Holy People, supernatural and sacred, who lived below ground in four lower worlds. A great flood underground forced the Holy People to crawl to the surface of the earth through a hollow reed, where they re-created the world each time they entered a new one. In the later worlds, Changing Woman gave birth to the Hero Twins, called "Monster Slayer" and "Child of the Waters" who had many adventures in which they helped to rid the world of much evil. Earth Surface People, mortals, were created in the fourth world, and First Man and First Woman were formed from ears of white and yellow corn. The gods gave them ceremonies, which are still practiced today.

Norse

Odin and his brothers used Ymir's body to create the universe. This universe comprises of nine worlds. They placed the body over the void called Ginnungagap. They used his flesh for creating the earth and his blood for the sea. His skull, held up by four dwarves (Nordri North, Sudri South, Austri East, and Vestri West), was used to create the heaven. Then using sparks from Muspelheim, the gods created the sun, moon and stars. While Ymir's eyebrows were used to create a place where the human race could live in; a place called Midgard. The first humans, Ask and Embla, were created from logs. [2]

Randomness

Some philosophers like Hakim Bey and occultists like Peter Carroll think randomness, chaos or the Uncertainty principle is the prime mover according to science, and should accordingly be treated as divine.

Surat Shabda Yoga

Surat Shabda Yoga cosmology depicts the whole of creation (the macrocosm) as being emanated and arranged in a spiritually differentiated hierarchy, often referred to as eggs, regions, or planes. Typically, eight spiritual levels are described above the physical plane, although names and subdivisions within these levels will vary to some extent by mission and Master. (One version of the creation from a Surat Shabda Yoga perspective is depicted at the Sant Ajaib Singh Ji Memorial Site in “The Grand Scheme of All Creation”.) All planes below the purely spiritual regions are subject to cycles of creation and dissolution (pralya) or grand dissolution (maha pralya).

The constitution of the individual (the microcosm) is an exact replica of the macrocosm. Consequently, the microcosm consists of a number of bodies, each one suited to interact with its corresponding plane or region in the macrocosm. These bodies developed over the yugas through involution (emanating from higher planes to lower planes) and evolution (returning from lower planes to higher planes), including by karma and reincarnation in various states of consciousness.

Taoism

Chapter 25 of The Book of Virtue states: 有物混成，先天地生。寂兮寥兮，獨立而不改，周行而不殆，可以為天地母 。吾不知其名，強字之曰道。 The LeGuin Rendition renders this as: "There is something that contains everything. Before heaven and earth it is. Oh, it is still, unbodied, all on its own, unchanging, all-pervading, ever-moving. So it can act as the mother of all things. Not knowing its real name, we only call it the Way." But no Taoist can tell you what this means.

Zen

Everything and nothing are all interconnected, inseparable, a whole. Zen denies that the person is the first cause. If it speaks of origins at all, it says that the ground of being is the real first cause.

Zoroastrianism

The Zoroastrianism story of creation has Ahura Mazda creating 16 lands, one by one, such that each would be delightful to its people. As he finished each one, Angra Mainyu applied a counter-creation, introducing plague and sin of various kinds.

See also

• Abrahamic religions
• Biblical cosmology
• Cosmogony
• Cosmological argument
• Cosmology (disambiguation)
• Creation evolution controversy
• Category:Creationism
• Creationism
• Creationist theology
• Creator god
• Dating Creation
• Day-Age Creationism
• Deism
• Evolution
• Evolutionary creationism
• Existence
• Gap Creationism
• Intelligent design
• Old Earth creationism
• Theism
• Timeline of the Universe
• Ultimate fate of the Universe
• Young Earth creationism

External links

• Creation Essentials, Creation Non-Essentials
• Creation Questions & Answers
• Discrepancies between Genesis 1 and Genesis 2 accounts
• Don't Gen. 1 and 2 present contradictory creation accounts?
• Indian cosmology
• Is Evolution a Creation Myth?
• Japanese Creation Myth
• Norse Creation Myth
• Popul Vuh

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