Perhaps the most fundamental and at the same time the least understood biological problem is that of the origin of life. It is central to many religious, scientific, and philosophical problems and to any consideration of extraterrestrial life.
Vladimir Ivanovich Vernadsky (1863-1945) was a Russian geochemist and mineralogist who is considered one of the founders of geochemistry and biogeochemistry. His scientific legacy was to give us reflections on the most profound issues ever tackled by man: What is life Is life a universal cosmic phenomenon and thus much older than the Earth itself, or is it a specific feature of our planet.
Vernadsky was of the opinion that an answer to this question could only be provided by the cosmos itself. According to Vernadsky, "Life is a cosmic phenomenon, rather than only a terrestrial one". In his notes written back in the years from 1917 to 1921, and published as a book 60 years later (Zhyva Rechovyna – ‘Living Matter'), Vernadsky defines living matter as an aggregate of living organisms which take part in geological processes. He figured out its characteristics, which included mass, chemical composition and energy.
Back in the 1910s, there was no firm scientific evidence available that would unequivocally show the possibility of living matter evolving from non-living matter. In fact, even today, many decades later, we still lack any proof that it is possible; neither do we have a smooth theory that would convincingly show how it could happen.
We do have an increasing amount of evidence, which suggests that the biosphere has influenced the geological processes; organic deposits in the earth’s crust and the composition of the atmosphere are clear indications of such influence.
But I am afraid that Vernadsky had the same blindside that most materialist have. He, for example, wrote in one of his letters, "Life is as much part of the Cosmos as energy and matter", but then he also had no idea about the importance of information.
Information is neither energy nor matter, it is something completely different it is sui generis. And energy is not something different from matter. In fact, energy is not something with substance, but like mass, energy is a quality of matter; energy is matter in motion, energy is movement. Where there is no matter there is no energy! Where there is no moving matter, there is no energy! Energy = Mass in motion, example of this: E = m.c^2.
There are several hypotheses of the origins of life, perhaps the most fundamental and at the same time, the least understood biological problem. It is central to many scientific and philosophical problems. Most of the hypotheses of the origin of life will fall into one of six categories:
- The origin of life is a result of a supernatural event; that is, one permanently beyond the descriptive powers of physics and chemistry. (Creation)
- Life, particularly simple forms, spontaneously and readily, arises from nonliving matter in short periods, today as in the past. (Spontaneous generation)
- Life is co-eternal with matter and has no beginning; life arrived on the Earth at the time of the origin of the earth or shortly thereafter. (Vernadsky’s view)
- Life arose on the early Earth by a series of progressive chemical reactions in a very, special, primordial soup. Such reactions may have been likely or may have required one or more highly improbable chemical events and very bizarre radiation. (Abiogenesis: not much different from spontaneous generation)
- Cosmic Ancestry is a new theory that is of the opinion that life on Earth was seeded from space, and that life’s evolution to higher forms depends on genetic programs that come from space.
- Hindus believe that everything including matter is alive so that there was not a separate creation act for life. Everything was created simultaneously and everything is alive. Panpsychism is the philosophical doctrine that every physical entity is conscious. Panpsychism is related but not equivalent to hylozoism (Greek hyle, matter + zoe, life), which says that every object is alive.
Vernadsky’s view is close to the third hypotheses. Toward the end of the 19th century the third hypothesis gained currency, particularly with the suggestion by Svante August Arrhenius (1859-1927) that life on Earth arose from Panspermia, microorganisms or spores wafted through space by radiation pressure from planet to planet or solar system to solar system (the fifth hypothesis).
Such an idea of course is surmised by many scientists to avoid, rather than solve the problem of the origin of life.
Among the oldest known fossils are those found in the Barberton area of the Mpumalanga Province in South Africa; they are dated at 3.1 billion (3.1 x 10^9) years old. These organisms have been identified as bacteria and blue-green algae (cyanobacteria).
Since the Earth is about 4.6 billion (4.6 x 10^9) years old, this suggests that the origin of life must have occurred within a few 100 million years of that time. The fossil record, in any complete sense, goes back only 645 million (645 x 10^6) years.
Earth in Hadean eon (from 4.6 to 3.8 billion years ago)
In the layers of sedimentary rock known by geological methods and by radioactive dating to be that old, most of the major groups of invertebrates appear for the first time. All these organisms appear adapted to life in the water, and there was no sign yet of organisms adapted to land. For this reason, and because of a rough similarity between the salt contents of blood and of seawater, it is believed that early forms of life developed in oceans or pools.
In Precambrian times, solar ultraviolet radiation, particularly destructive to nucleic acids, may have penetrated to the surface of the earth, rather than being totally absorbed in the upper atmosphere by ozone (O3) as it is today. In the absence of ozone, the ultraviolet solar flux is so high that a lethal dose for most organisms would be delivered in less than an hour.
Life near the Earth’s surface would have been impossible. As the amount of atmospheric oxygen and ozone increased, mostly due to plant photosynthesis, life increasingly close to the Earth’s surface would have been possible. It has been suggested that the colonisation of the land, about 425 million (425 x 10^6) years ago, was possible only because enough ozone was then produced to shield the surface from ultraviolet light for the first time.
According to Vernadsky, life then had insinuated itself between the Sun and the Earth. It diverted solar energy to its own uses and contrived more and more ways of exploiting more and more environments. Some ‘experiments’ were less successful and the lines became extinct; others were more successful and the lines filled the Earth. He concluded that evolution through natural selection directed the proliferation of a growing array of life forms throughout the biosphere.
As we see, modern science of the end of the late twentieth, early twenty-first century has adopted – and adapted – some of Vernadsky’s ideas expounded by him decades ago.
Cosmic Ancestry is a new theory pertaining to evolution and the origin of life on Earth. It holds that life on Earth was seeded from space, and that life’s evolution to higher forms depends on genetic programs that come from space. (It accepts the Darwinian account of evolution that does not require new genetic programs) It is a wholly scientific, testable theory for which evidence is accumulating.
The first point, which deals with the origin of life on Earth, is known as Panspermia (also called 'directed Panspermia'), literally, 'seeds (sperm) everywhere'. Its earliest recorded advocate was the Greek philosopher Anaxagoras (500-428 BC), who influenced Socrates (470-399 BC). However, Aristotle’s theory of spontaneous generation came to be preferred by science for more than two thousand years.
Then on April 9, 1864, French chemist Louis Pasteur (1822-1895) announced his great experiment disproving spontaneous generation as it was then held to occur.
In the 1870s, Lord Kelvin (1824-1907) and Hermann von Helmholtz (1821-1894) reinforced Pasteur and argued that life could come from space. Moreover, in the first decade of the 1900s, Arrhenius (1859-1927) theorised that bacterial spores propelled through space by light pressure were the seeds of life on Earth.
According to Isaac Asimov (1920-1992), Toward the end of the nineteenth century some theorists went to the other extreme and made life eternal. The most popular theory was advanced by Arrhenius (the chemist who had developed the concept of ionisation).
In 1907, he published a book, entitled Worlds in the Making, picturing a universe in which life had always existed and migrated across space, continually colonising new planets. Life travelled in the form of spores that escaped from the atmosphere of a planet by random movement and then were driven through space by the pressure of light from the sun. (Isaac Asimov, New Guide to Science, 1984)
However, in the 1920s, Alexander Oparin (1894-1990) and JBS Haldane (1892-1964), writing independently, revived the doctrine of spontaneous generation in a more sophisticated form. In the new version, the spontaneous generation of life no longer happens on Earth, takes too long to observe in a laboratory, and has left no clues about its occurrence.
Supporting this theory, in 1953, Stanley Miller (1930- ) and Harold Urey (1893-1981) showed that some amino acids could be chemically produced from ammonia and methane. That experiment is now famous, and the Oparin-Haldane paradigm still prevails today.
Starting in the 1970s, Fred Hoyle (1915-2001) and Chandra Wickramasinghe (1939- ) rekindled interest in Panspermia. By careful spectroscopic observation and analysis of light from distant stars, they found new evidence, traces of life, in the intervening dust. They also proposed that comets, which are largely made of ice water, carry bacterial life across galaxies and protect it from radiation damage along the way.
One aspect of this research program, that interstellar dust and comets contain organic compounds, has been pursued by others as well. It is now accepted by some scientists that space contains the 'ingredients' of life. This development could be the first hint of a huge paradigm shift. Nevertheless, mainstream science has not accepted the hard core of modern Panspermia, that whole cells seeded life on Earth.
Hoyle and Wickramasinghe also broadened or generalised Panspermia to include a new understanding of evolution. While accepting the fact that life on Earth evolved over the course of about 4.6 billion (4.6 x 10^9) years, they say that the genetic programs for higher evolution cannot be explained by random mutation and recombination among genes for single-celled organisms, even in that long a time: the programs (software) must come from somewhere beyond Earth.
Hoyle, the originator of the steady state universe theory (which he later abandoned), after spending several years writing science fiction books, wrote a book with Wickramasinghe in 1979, called Lifecloud: the Origin of Life in the Universe. In the book, they first list solid evidence why it would be impossible for life to begin here on earth, and then they present their theory that life originated in living creatures feeding, breeding, and multiplying (in comets) which managed to arrive here! Science fiction writers make good evolutionary theorists. In fact, you can hardly tell the two apart when you pick up their books.
Hoyle has also come up with a theory on the origin of life which says that life on earth was seeded by colliding comets. In a book review of Hoyle and Wickramasinghe’s book, Lifecloud: the Origin of the Universe, Colin Pillinger (1943- ) accuses the authors of selecting their evidence and elevating speculation to fact.
For a time, Hoyle and Wickramasinghe held to this comet origin of life seeds. Their view was that, since it is impossible for life to form on earth; it must have formed in the tails of comets and gas clouds in the sky! The near absolute zero temperatures (absolute zero = -273.15 degrees centigrade) in hydrogen clouds might, it was theorised; provide better conditions for the formation of life than sand, seawater, and lightning bolts on earth.
Another theory of Hoyle’s was developed two years later: life forms continually reach the earth directly from outer space. How do they get here They ride light beams! As fast as one theory is shot down, another ‘pops up’. Hoyle and Wickramasinghe explained the light-beam theory in their 1981 book, Evolution from Space. George F Howe discusses their conjectures:
“Like their counterpart in life science, Dr Francis C Crick of DNA fame, Hoyle and Wickramasinghe seriously suggest that packets of genetic material continually enter our atmosphere from outer space, riding the pressure of light between stars. These may be mere specks of genetic code stuff (in their view), entire bacteria, or even insect eggs. Some source out there, they believe, is benevolently broadcasting these materials widely and is thus providing pre-designed systems that any forms of life may need to adapt for whatever environmental niches they may be encountering on particular planets. Where successes occur, they envision completely new blocks of genes entering the cell and producing new functions about the way a computer can be rapidly 'upgraded'.”
“Like the Darwinism that Hoyle and Wickramasinghe’s model is supposed to replace, cosmic evolution suffers at precisely the same points: lack of any adequate mechanism and absence of experimental supporting data. They are obviously unable to show the reader strong evidence of such genetic packages in astronomical debris entering our atmosphere. It seems this (and this alone) is the key evidence required to put this interesting origins model on some sort of scientific basis.”
Pasteur’s work discouraged many scientists from discussing the origin of life at all. Moreover, they were anxious not to offend religious feeling by probing too deeply into the subject. Although Charles Darwin (1809-1882) would not commit himself on the origin of life, others subscribed to the fourth hypothesis (abiogenesis) more resolutely, notably TH Huxley (1825-1895), and John Tyndall (1820-1893) in his ‘Belfast Address’ of 1874.
Although Huxley and Tyndall asserted that life could be generated from inorganic chemicals, they had extremely vague ideas about how this might be accomplished. The very phrase 'organic molecule' implies that there exists a special class of chemicals uniquely of biological origin, despite the fact that organic molecules have been routinely produced from inorganic chemicals since 1828.
Briefly, Huxley and Tyndall’s theory holds that all of life comes from space. It incorporates the original Panspermia in the same way that General Relativity incorporates Special Relativity. Their expanded theory can well be termed 'strong' Panspermia. It means, simply, that we might all be aliens.
It is an idea that has been around longer than Christianity, but which still struggles to gain strong support among most scientists.
However, two recent discoveries are breathing new life into the theory:
- One study, reported in the October 27, 2000 issue of the journal Science, shows that a space rock could successfully transport life between planets.
- Another group of researchers, reporting in the October 19, 2000 issue of Nature, claims to have found and revived bacteria on Earth that were dormant, in the form of spores, hiding in New Mexican salt crystals for 250 million years. Scientists called the implications of this second discovery profound, suggesting that if further study bears out the findings, it could mean bacterial spores are nearly immortal.
Moreover, if you are immortal, then what are a few billion years of interstellar travel “Until recently, Panspermia was not even regarded as a scientific hypothesis,” says Chandra Wickramasinghe, the concept’s leading proponent. “Now that has changed.”
Francis Crick (1916- ) fills the first half of his 1981 book, Life Itself, with reasons why life could not originate on our planet – and then he proceeds to suggest that it came from outer space on rockets!
“Crick proposed that life began somewhere else in the universe and evolved to a much higher technical level than is now present on earth. He next suggests these life forms are now sending rockets containing primitive life forms (perhaps bacteria or blue-green algae) throughout the universe, spreading the seeds of life hither and yonder. Crick even describes the rocket’s design and postulates the conditions necessary for successful re-entry into our atmosphere.” (Richard Tkachuck, in a book review in Origins, Vol. 10, No. 2, 1983)
"The Monolith" of Arthur C. Clarke's novels.
In Life Itself, Crick embraces an origins view called ‘Directed Panspermia', in which it is assumed that life was originally sent to earth from outer space! According to Crick, life evolved from non-life on some other planet, starting with the spontaneous generation of bacteria, and proceeding all the way to highly intelligent beings.
Cosmic Ancestry implies that life can only descend from ancestors at least as highly evolved as itself. And it means we believe that there can be no origin of life from nonliving matter in the past.
As the romantics maintain, we are stardust, or more practically, we are nuclear waste. At least our bodies (hardware) are. It seems that every physical thing in the universe was created at one place and then transported, or blown, to another; we are space travellers, and who knows where we are from However, where are our souls (software) from?
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