JournalofCosmology.com, May, 2010
Panspermia, Genetics, Microbes, and
Viral Visitors From the StarsRhawn Joseph, Ph.D.1, and Rudolf Schild, Ph.D.2,
1Emeritus, Brain Research Laboratory, Northern California,
2Center for Astrophysics, Harvard-Smithsonian, Cambridge, MA
Keywords: Origin of life, Astrobiology, Extraterrestrial Life, Panspermia, Abiogenesis, Colliding Galaxies, Nebula, Nebular Clouds, DNA, Comets, Viruses, Archae, Bacteria, Horizontal Gene Transfer, Evolution.
1. Origins: Life Began in A Nebular Cloud
There is a growing body of evidence demonstrating that life did not begin on this planet but began billions of years before Earth was formed (Anisimov 2010; Gibson and Wickramasinghe 2010; Goertzel and Combs, 2010; González-Díaz, 2010; Jose et al., 2010; Joseph 2009a; Joseph and Schild 2010; Line 2010; Poccia et al., 2010; Sharov 2009, 2010). There is also considerable evidence that the evolution of life on Earth has been directly impacted by viral and microbial genes which were acquired from life forms living on other planets (Joseph 2000, 2009b,c).
As detailed by Joseph and Schild (2010), life could not have begun on this planet for the following reasons: A)Complex life was present on Earth almost from the beginning with evidence of biological activity dated to between 4.2 to 3.8 billion years ago (Nemchin et al. 2008; O'Neil et al. 2008; Mojzsis, et al., 1996; Pflug, 1978; Rosing, 1999, Rosing and Frei, 2004). B) Statistically, there was not enough time to create a complex self-replicating organism on this planet (Crick 1981; Horgan, 1991; Hoyle, 1974, 1982; Yockey 1977). C) DNA and complex organic molecules would have been destroyed by the environment of the early Earth (Crick 1981; Ehrenfreund and Sephton 2006). D) All the essential ingredients for creating life were missing on the new Earth, including, and especially oxygen, sugar, and phosphorus (Crick 1981). E) Even proto-organisms would not have been able to surive on Earth. F) The reproductive strategies of Viruses which require a living host, proves an Earthly "RNA World" is imaginary and could not have created life on Earth (Joseph 2000).
By contrast, analysis of the eukaryotic and prokaryote genome has led a number of scientists to conclude that life in this galaxy may have begun over 10 billion years ago in an extra-stellar environment (Anisimov 2010; Jose et al., 2010; Sharov 2009, 2010). Based on a detailed analysis of genetics, astrobiology, and astrophysics, Joseph and Schild (2010) concluded that nebula are cradles of life, and life began in a nebular cloud--a view which is concordant with the views of Hoyle and Wickramasinghe (Burbidge, Burbidge, Fowler and Hoyle, 1953; Hoyle and Wickramasinghe 1978). All the essential ingredients may be available in nebular clouds which are produced by supernova (Burbidge, Burbidge, Fowler and Hoyle, 1953; Joseph and Schild 2010). As the Milky Way galaxy, with its estimated 4 billion stars, has an age of 13.6 billion years (Pasquini et al., 2005), and since supernova were more common during the early stages of galaxy formation, thereby creating billions of bio-chemically complex nebular clouds, life had billions of locations and billions of years to evolve from chemicals, gasses and metals, to organic compounds, to self-replicating nano-proto-cells, to simple cells equipped with DNA (Joseph and Schild 2010). However, life only need to have been established once, and its descendants could have easily spread across the cosmos. And yet, in the vastness of the cosmos, it may be that life developed independently at least twice and maybe even multiple times in completely different environments.
2. The "Universal Genetic Code" vs Multiple Origins of Life?
At present, three domains of life are recognized: Archae, Bacteria, and Eukaryotes. There is considerable debate about the nature of Nanobacteria (Ciftcioglu et al., 2006; Martel and Young 2008) and controversy over evidence suggestive of a Nanobacteria DNA genome (Miller et al., 2004). However, if alive, Nanobacteria would expand the domains of life to four. Viruses are not considered to be alive, but if they were, their inclusion could expand the domains of life to five or more, i.e. Viruses with RNA genomes, Viruses with DNA genomes, endogenous retroViruses, and so on. What other domains of life are yet to be discovered?
Is the "Universal Genetic Code" a prerequisite for life?
Be it a universe which began with a Big Bang, or an infinite, eternal universe with infinite time, it could well be that through endocytosis, phagocytosis, and genetic mechanisms involving gene transfer, that extreme variations in genetic coding were eventually averaged out, or that one code won out due to natural selection as it was the superior code. Thus, even if "non-DNA" life forms were to emerge they would acquire a genome upon encountering DNA-based life which successfully inserts its genes thereby giving rise to a universal genetic code which is common to all life. Just as there is evidence that Archae, Viruses and Bacteria may have mixed and combined their genes to fashion the first multi-cellular Eukaryotes (Joseph 2009b,c), non-DNA life forms or those with inferior genetic codes may have acquired a "universal" DNA-based genome following the transfer, insertion, and mixing of genes, such that one genetic code became universal. If these propositions are true, then different domains of life and of quasi-life, could have arisen in completely different environments and localized conditions, e.g. nebular clouds, the interior of comets, on different planets, or in the case of Viruses within RNA-worlds.
The first steps toward life began with all the chemicals necessary for life, and nebular clouds are the most likely environment where they may accumulate (Burbidge, Burbidge, Fowler and Hoyle, 1953; Joseph and Schild 2010). Further, the unique environment of nebula is ideal for synthesizing and promoting the evolution of these molecules. For example, hydrogen, oxygen, carbon, calcium, sulfur, nitrogen and phosphorus are continually irradiated by ions (Osterbrock and Ferland 2005), which can generate small organic molecules which evolve into larger complex organic molecules thereby resulting in the formation of amino acids and other compounds. Furthermore, polarized radiation induces asymmetric photochemistry leading to homochirality and the induction of chiral asymmetry which can produce an excess of L-amino acids (Bailey, et al., 1998; Fukue et al. 2010; Sidharth, 2009; Troop and Baily 2009; Wirström et al., 2007), and thus the formation of proteins, nucleobases and then DNA. For example, the combination of hydrogen, carbon, oxygen, nitrogen, cyanide and several other elements, could create adenine, which is a DNA base, whereas oxygen and phosphorus could ladder DNA base pairs together. Further, glycine has been identified in the interstellar medium (Kuan, et al., 2003). Hence, the building blocks for DNA could have been generated or combined within interstellar clouds and DNA would become part of this molecular-protein-amino acid complex (Joseph and Schild 2010).
Be it a nebular clouds, comet, or some other source, once a nanoparticle with attributes identical to a Nanobacteria was fashioned, it could easily provide a hollow core where phosphates interact with sugars similar to glycerol, to produce acids. Lipid-like structures would result. As is well known, lipids can self-assemble and form bilayers, vesicles and hollow cellular-like membranes held together by non-covalent interactions. Therefore, even in the absence of DNA, nano-particles fashioned in a nebular cloud or comet, could grow in size and complexity, self-replicate, and utilizing chemicals and compounds freely available in its environment, develop a semi-permeable proto-membrane. An interior or exterior permeable membrane would allow for ion and nutrient transport, storage, the absorption and generation of energy, and then synthesis even in the absence of enzyme-catalyzed reactions. Moreover, the presence of hydrocarbons (catalyzed by stellar radiation), once incorporated, could be employed for polymerization and the additional creation and assembly of the necessary elements and macromolecules essential for life. Further, in the presence of multiple sources and types of energy, radiation, and hydrogen gasses, and through natural selection, the nano-particle membrane would evolve capacitance. A metabolically energized semi-permeable membrane would then promote the creation of peptides, with plasma hydrogen or other hydrogen gasses acting as an energy source.
It must be stressed that the model presented above is an extremely simplified schemata of the immensely complex interactions which would be required and presupposes conditions where all the necessary elements were available. Moreover, the steps leading from the random mixing of chemicals to the first nano-particle would likely require hundreds of millions and even billions of years before the first self-replicating molecular compound was fashioned. Moreover, even after billions of years, the first replicon may not have possessed DNA.
These steps leading from self-replicating chemical compound to the complexity of a DNA-equipped organism, could not have taken place on Earth as all the essential ingredients were missing and there was simply not enough time. Phosphorus, for example, is rare in this solar system and may have been non-existent on the early Earth, and phosphorus is essential for the manufacture of DNA.
By contrast, it is highly likely that all the ingredients and conditions necessary for building complex molecular organic structures, amino acids and proteins are present in nebular clouds, including phosphorus, calcium, water, carbon, and oxygen which when mixed together and irradiated might easily produce self-replicating nano-crystal-particles. It has been reported that "CaCO3 precipitates prepared in vitro are remarkably similar to purported Nanobacteria in terms of their uniformly sized, membrane-delineated vesicular shapes, with cellular division-like formations and aggregations in the form of colonies" (Martel and Young 2008). Calcium is a metal and reacts to water and hydrogen. Calcium is also produced by stellar nucleosynthesis (Arnett 1996; Hansen et al., 2004; Mezzacappa and Fuller, 2006), and is thus injected into nebular clouds, along with hydrogen, (calcium), carbon, and oxygen; i.e. H,Ca,C,O. Although CaCO3precipitates are not alive and cannot be considered a proto-organism, these essential ingredients are present in nebular clouds. Thus it can be predicted that due to turbulence, supernova, stellar ignition, and other forces, that these and other complex organic molecules were combined within nebular clouds to create life-related structures, which eventually resulted in a self-replicating nano-particle with a semi-permeable membrane.
Given that energy and all the necessary life-sustaining molecules were also present, once equipped with DNA, even if consisting only of 4 base pairs, this complex molecular proto-cellular structure would have begun evolving. With every replication its genome would have expanded, and coupled with natural selection, it would have become more variable and more complex.
Further, these combinations would be buffeted by cosmic shock waves from additional supernova thereby providing these coalescing organic molecules and strands of DNA with heat and additional sources of energy. Eventually this energized DNA-membranous-protein complex would have begun to function as a proto-organism or proto-viral replicon with all its needs provided by the chemically enriched nebular environment. The next steps would lead to microbial life. Once the first microbe was fashioned, it immediately began replicating and creating billions and then trillions of variable copies of itself and its DNA.
4. Born in Space. Archae, Bacteria and Viral Visitors from the Stars
Archae form one of the three recognized domains of life. Many species of Archae commonly inhabit extreme environments, a behavioral life style they share with some species of Bacteria (Kimura et al, 2006, 2007; Leininger et al., 2006; Robertson et al., 2005). However, they are completely distinct from Bacteria, particularly in regard to the size of their genomes, preferred environments, and cell membranes. For example, Archae genomes are relatively smaller and more compact and less variable in size ranging from 0.5 Mb to 5.5 Mb (Maeder et al., 2006; Waters et al., 2003). Bacterial genomes can vary by two orders of magnitude, from 180 kb in an intracellular symbiont, Carsonella (Nakabachi et al., 2006), to 13 Mb in Sorangium cellulosum which dwells in soil (Schneiker et al., 2007). In addition, Archaean membranes are made of ether lipids whereas Bacterial cell membranes are created from phosphoglycerides with ester bonds (De Rosa et al., 1986).
It is the significant differences in their cell membranes and the environments they prefer which may give a clue to their differential origins. Bacteria are usually the most common form of life in the soil whereas Archae are the most common form of life in the ocean dominating ecosystems below 150 m in depth (Karner et al., 2001; Robertson et al., 2005). Might this suggest that the ancestry of Archae leads to a watery environment, such as a comet, whereas Bacterial origins lead to a proto-planet enshrouded in a nebular cloud? Might the Archae preference for extreme environments provide yet another clue? Unfortunately, at present there is insufficient evidence to even speculate beyond the simple fact that the Archae and Bacteria of Earth have an ancient genetic pedigree which leads to an other-worldly environment; i.e. interstellar space (Joseph 2000, 2009b,c).
Microbes born on this planet are already pre-adapted for journeying through space, living in space (Burchell et al. 2004; Burchella et al. 2001; Horneck et al. 1994, 2001a,b; Mastrapaa et al. 2001), and not just surviving but flourishing under incredibly toxic and deadly conditions (Delgado-Iribarren et al. 1987; Jaffe et al. 1985; Gerdes et al. 1986; Herrero et al. 2008; Hiraga et al. 1986; Hayes 2003; Martinez & Perez-Diaz 1990). Many species of microbes thrive in radioactive environments where they are continually exposed to radiation by ions similar to what might be encountered in a nebular cloud.
In 1958, physicists discovered clouds of Bacteria, ranging from two million Bacteria per cm3 and over 1 billion per quart, thriving in pools of radioactive waste directly exposed to ionizing radiation and radiation levels millions of times greater than could have ever before been experienced on this planet (Nasim and James, 1978). The world's first artificial nuclear reactor was not even built until 1942. Prior to 1945, poisonous pools of radioactive waste did not even exist on Earth. And yet, over a dozen different species of microbe have inherited the genes which enable them to survive conditions which for the previous 4.6 billion years could have only been experienced in space. These radiation-loving microbes include Deinococcus radiodurans, D. proteolyticus, D. radiopugnans, D. radiophilus, D. grandis, D. indicus, D. frigens, D. saxicola, D. marmola, D. geothermalis, D. murrayi.
Many types of Viruses are also radiation resistant (Fekete et al., 2005; Gibbs et al., 1978; Hijnen et al., 2006; Jung et al., 2009). Moreover, freezing temperatures will increase the radiation resistance of various species of Virus (Jung et al., 2009). Thus, Viruses, Bacteria, Bacterial spores, protozoon, lichens, fungi and algae, are radiation resistant (Hijnen et al., 2006; Lovett 2006; Sancho et al. 2005) and they could have only acquired this resistance through the inheritance of genes passed on through natural selection following exposure in a radioactive environment other than Earth.
Like Bacteria, Viruses have been shown to survive simulated extraterrestrial conditions (Fekete et al., 2004; Walker, 1970). For example, in one set of experiments, bacteriophage T7 and isolated bacteriophage T7 DNA were exposed to space conditions in the international space station including vacuum and UV radiation and temperatures of 0°C. It was determined that DNA lesions will accumulate but the amount of damage is inversely proportional to the thickness of shielding and layers (Fekete et al., 2005). With increased shielding, such as might be expected if encased in a meteor, asteroid, or comet, the damage is minimal. Further, following simulated space conditions including prolonged radiation, up to 60% of T7 phages remained active and were able to infect Bacterial host cells, and those phages suffering damage were able to fully recover (Fekete et al., 2004).
Viruses, including those with double-stranded DNA genomes have also been shown to survive in the most extreme of environments (Pagaling, et al., 2007; Prangishvili et al., 2006; Rice et al., 2004; Romancer et al., 2007; Walker,1970) including extremely acidic hot springs with temperatures up to 93°C, and pH 4.5 (Häring et al., 2005; Rice et al., 2001, 2004), in hypersaline water at saturation (Porter et al., 2007), a well as in deserts, soda lakes, deep sea thermal vents, and under incredible hydrostatic pressures (Romancer et al., 2007). Likewise, wild type filamentous phage M13 retained their nucleic acid integrity and protein structure despite high pressure and even simulated silicification (Hall et al., 2003).
Archae viruses, and other prokaryotic extremophiles, are able to flourish under these same life-neutralizing conditions (Pagaling, et al., 2007; Porter et al., 2007; Prangishvili et al., 2006; Rice et al., 2004; Romancer et al., 2007).
5. DNA From Space: Prokaryotes and Viral-Genetic-Storehouses
Archae and Bacteria are distinguished by the company they keep, i.e. Viruses. There are Viruses which selectively target Eukaryotes, others which prefer Bacteria, and those which are found in association with Archae. Moreover, just as Archae and Bacteria significantly differ, so too do Viruses which target Archae vs Bacteria (Hendrix, 2004; Pagaling, et al., 2007; Prangishvili et al., 2006; Rice et al., 2004). Although the tailed phages of Archae and Bacteria share many features which could argue for shared ancestry (Newcomb et al, 2001; Rice et al., 2004), sequence analysis of the circular double-stranded DNA Archae-viral genome shows it shares little similarity to other known genes in Viruses (Prangishvili et al., 2006). In fact, all Archaeal Viruses discovered so far have DNA genomes (Ackermann, 2007; Prangishvili et al., 2006; Rice et al., 2004) whereas the genomes of Bacterial Viruses are either RNA or DNA.
If some Viruses evolved into Bacteria and others into Archae, if they coevolved from simpler proto-cells which originated in different environments, of if Viruses are manufactured by the Bacterial and Archae genome and then ejected as packet of plasmid-DNA, is unknown. However, considerable evidence has been marshaled which demonstrates that Viruses are utilized by Bacteria as vast storehouses of genes and DNA, which may be transferred from Viruses to Bacteria, and then back again, depending on environmental and other conditions which impact Bacterial needs and requirements (Joseph 2009b,c).
Viruses store vast amounts of genetic information and hundreds of genes which provide no direct benefit to the Virus. The Virus serves the host by storing genes which can be selectively acquired depending on need, and thus freeing up genetic space in the host's genetic machinery which need only maintain those genes necessary for its survival and functional integrity. Thus, Viruses act as gene conservatories and can increase the gene pool within the genome of a host when necessitated by changing environmental conditions (Sullivan et al., 2006; Zeidner et al., 2005).
It is likely that Viruses found in association with Archae provide a similar genetic-satellite function, orbiting in close proximity and acting as a store house for genes which may be required by Archae when confronted with life-threatening challenges.
Giant double-stranded DNA Viruses (such as Acanthamoeba polyphaga, MimiVirus), with particle sizes of 0.2 to 0.6 microm, genomes of 300 kbp to 1,200 kbp, and commensurate complex gene pools (Claverie 2005) contain incredible genomic capacity and an extensive gene library which was likely obtained via horizontal gene transfer from a host to the Virus. These giant double-stranded DNA Viruses, such as Poxviridaem also have double-stranded linear DNA genomes which are larger than most Bacteria.
Figure 20. Cyanobacteria.
As first proposed, theorized and detailed by Joseph (2000), as Bacteria and Viruses journeyed from planet to planet and solar system to solar system, they exchanged DNA via horizontal gene transfer, with the denizens of these worlds, thus making their survival on these planets possible through the immediate acquisition of the necessary genes. Genes not necessary for survival were then placed in genetic storage, i.e. within a Virus. However, when these microbes and their viral luggage are transported to yet other worlds, these genes, when activated in response to specific environmental triggers, allow these microbes to colonize different environments be they radioactive, poisonous, or toxic (Joseph 2009b,c). Thus, Viruses and the prokaryotic (Bacteria and Archae) genome contain genes which enable them to survive, flourish and proliferate in, and adapt to the most extreme of toxic and poisonous environments (Jaffe et al. 1985; Gerdes et al. 1986; Hiraga et al. 1986; Hayes 2003; Pagaling et al., 2007; Prangishvili et al., 2006; Romancer et al., 2007; Walker,1970), be it extremely acidic hot springs, soda lakes, deep sea thermal vents, hypersaline water at saturation and under incredible hydrostatic pressures (Häring et al., 2005; Porter et al., 2007; Rice et al., 2001; Romancer et al., 2007). Likewise, Bacteria (and their viral associates) flourish in pools of radioactive waste, and at subzero temperatures, within boiling hot springs, or miles beneath Earth or at the bottom of the sea (Boone et al. 1995; Fekete et al., 2004, 2005; Gilichinsky 2002a,b; Nicholson et al. 2000; Setter 2002).
If we accept the basic premise of "natural selection" then the existence, inheritance, and preservation of these genes indicates these genes existed prior to exposure on Earth (Joseph 2000, 2009b,c). Therefore, the ancestors of these species were exposed to these substances and environments prior to arriving on Earth.
Microbes and Viruses act as interplanetary genetic messengers.
Therefore, microbial creatures, and their DNA, are perfectly adapted for traveling from planet to planet and from solar system to solar system, and have acquired and inherited the genes which enable them to survive in almost any environment such as might be encountered on other worlds. They also acquired eukaryotic genes coding for complex physical organs, features, characteristics, and traits (Joseph 2000, 2009b,c). Nearly 4.6 billion years ago, these microbes, which were accompanied by Viruses and their vast genetic libraries, arrived on this planet, and this is how life on Earth began. And then this life began to terraform the Earth, and to evolve.
6. Spores from Space
It can be predicted that as life flows throughout the cosmos, that an infinite number of microbes would have died as they journeyed through space. Hoyle and Wickramasinghe (2000) in fact discovered evidence of mass microbial death; i.e. clouds of cosmic dust comprised of dead desiccated Bacteria (Allen and Wickramasinghe, 1981). Additional evidence of desiccated Bacterial dust was provided by telescope observations of the galactic centre infrared source GC-IRS7 (Allen and Wickramasinghe, 1981) and of fluorescence phenomenon and extended red emissions in nebula and extragalactic systems, i.e. biological chromophores (pigments), including chloroplasts and phytochrome.
However, millions of trillions would have lived. When subjected to life neutralizing conditions, or if the environment becomes incredibly hot, cold, or devoid of water, oxygen, or other life sustaining necessities, the microbial cell body will lose water and quickly shrink in size and form a highly mineralized core enclosed in heat and cold shock proteins which wrap around and protect them creating an almost impermeable shield. Bacteria accomplish this, in part, by secreting an additional protective membrane inside the outer membrane, and by shrinking as it loses water to the size of a microscopic spore. They will also saturate their DNA with acid soluable proteins which alters the enzymatic and chemical reactivity of its genome making it nearly invulnerable to harm (Marquis and Shin 2006; Setlow and Setlow 1995).
Bacteria can in fact sense a life-threatening event even before it occurs and will undergo a sequence of developmental changes to protect itself from death--often with the aid of a Virus which immediately transfers spore-triggering genes into the Bacterial genome. These microbes immediately begin to transform, secreting protective gels, shrinking to the size of spores, and generating heat and cold-shock proteins which wrap around and protect them. The resulting spore then becomes dormant (Marquis and Shin 2006; Setlow and Setlow 1995). "In the dormant stage a spore has no metabolism and resists cycles of extreme heat and cold, extreme desiccation including vacuuum, UV and ionizing radiation, oxyidzing agents and corrosive chemicals (Nicholson et al. 2000).
In fact, space experiments have shown that Bacteria and fungal spores can easily survive the vacuum and constant exposure to solar, UV, and cosmic radiation with just minimal protection (Horneck 1993; Horneck, et al., 1995). In the Long Duation Exposure Facility Mission, spores of B. subtilis were exposed to the the vacuum of space, UV radiation and cosmic rays for nearly 6 years. In each sample, thousands of spores survived (Horneck et al., 1994). However, survival rates increase significantly from 30% to 70% if coated with dust, or embedded in salt or sugar crystals (Horneck et al., 1994). In fact, Bacterial spores embedded in salt crystals have survived and have been brought back to life even after hundreds of millions of years (Dombrowski, 1963 Vreeland, et al., 2000).
Vreeland and colleagues (2000) discovered Bacteria spores which had been embedded in salt crytals buried 569 meters beneath the earth, and dating back 250 million years. These dormant spores, Bacillus permians, also came back to life and began to multiply. In 1963, H. Dombrowski also brought back to life Bacteria which had been embedded in salt deposits from the Middle Devonian, the Silurian, and the Precambrian (Dombrowski, 1963). Some of these Bacterial spores manged to survive for over 600 million years.
Thus it can be predicted that Bacteria spores could journey across the cosmos for up to 600 million years. And once they fell upon a suitable planet, they could go forth and multiply. Moreover, due to bolide impact which would cast debris into space, microbes such as Archae, living deep within that debris, need not become spores and could easily survive.
7. Panspermia: Distribution of Life in the Galaxy.
Viruses and microbes are preadapted for traveling through space and it can be assumed they would not have evolved these capabilities if their entire ancestral and genetic history had been confined to Earth and the conditions of this world. These genes could have only been inherited from Viruses and microbes who were born in or who lived in space. Thus, because of these genes, even Earthly microbes and Viruses are perfectly adapted for journeying from planet to planet, from solar system to solar system, and even from galaxy to galaxy.
Although a variety of mechanisms have been advanced for planet and star formation, most scientists agree that planets and stars originate in nebula clouds or proto-planetary discs which form in nebular clouds. Therefore, life in a nebular cloud could easily proliferate and spread from planet to planet during even the earliest stages of planet formation.
However, even if we were to confine the origin of life to a single comet, nebular cloud, or planet, the descendants of that life would inevitably be distributed to other planets and solar systems.
For example, a microbe ejected from a planet orbiting the star Alpha Centauri could reach Earth in 9,000 years (Arrhenius, 2009). There are 29 other stars within 12 ly of Earth and which are similar enough to the sun to possibly sustain life on orbiting planets. A single microbe could be ejected from any one of them and reach our planet in 25,000 years. Even stars 250 ly (and 515,000 years) away could deliver Viruses and living spores to Earth and other planets. In fact, only a single microbe needs to survive to repopulate and cover a suitable planet with microbial life (Joseph 2000, 2009a).
Any planet with oceans, atmosphere, and surface dwelling organisms will inevitably seed surrounding moons and planets with microbes and possibly eukaryotic life (Joseph 2000, 2009a). Microbial organisms from a single source may even come to be distributed on a galaxy-wide scale, some of which would come into contact and exchange DNA with microbes expelled from other living worlds (Joseph 2000, 2009b).
The mechanisms of dispersal are many and include A) Solar winds, B) Bolide Impact, C) Comets, D) Ejection of living planets prior to supernova which are then captured by a newly forming solar system, E) Galactic collisions and following the exchange of stars between galaxies.
8. Solar Winds.
A living planet with an atmosphere, orbiting within the habitable zone of a sun-like star, will be subjected to that star's solar winds. In the case of Earth, the powerful magnetic field protects the planet from these winds. Howevever, these winds will periodically increase significantly in strength and eject air-born microbes into space and distribute them not just to neighboring planets, but outside the solar system where they may come to contaminate collections of "Oort cloud" stellar objects and passing comets. After hundreds of millions of years survivors may fall upon a planet orbiting a distant star.
Air is an ideal transport mechanism and serves as a major pathway for the dispersal of Bacteria, Virus particles, algae, protozoa, lichens, and fungi including those which dwell in soil and water. Distinct species of over 1,8000 different types of Bacteria and other microbes thrive and flourish within the troposphere, the first layer of the Earth's atmosphere (Brodie et al. 2007). Microorganisms and spores have been recovered even at heights of 130,000 feet (Soffen 1965).
During the Monsoon season of tropical storms, microbes circulating in the troposphere and even those residing on the surface of the oceans and earth would easily be lofted into the stratosphere which sits just above the troposphere and extends from 8 km (5 miles) to 50 km (31 miles) in altitude. The monsoon is one of the most powerful atmospheric circulation systems on Earth and commonly funnels air, dust, water, gases, and pollutants from the lower layers of the atmosphere to deep within the stratosphere where they stay aloft and circulate the globe for years (Randel et al., 2010). Further, there is a normal pattern of seasonal upwelling where water, methane, and other gases are transported to the stratosphere in the subtropics and polar regions, by semiannual oscillations in weather, climate, and other factors related to the changing seasons (Randel et al., 1998). Thus, it can be readily assumed that microbes not only flourish in the troposphere, but are commonly lofted into the stratosphere.
Normally, such creatures might be too heavy to be ejected into space. However, when the CME struck on Sept. 24, 1998, the pressure of the solar wind jumped to 10 nanopascals whereas normally the pressure is around 2 or 3 nanopascals. Naturally airborne microbes living in the upper atmosphere would have also been cast into space (Joseph 2009a).
Therefore, it can be predicted that these solar events are not uncommon and must take place on innumerable habitable planets orbiting within a habitable distance from their sun.
Once lofted into space, microbes and spores might easily survive. Microbes and spores are so small that even when bombarded with photons and deadly gamma and UV rays the likelihood they would be struck is infestimally minute. Even if struck, the radiation dose would be minimal and the damage might not be fatal. If the organism's DNA is damaged, it can be rebuilt when the spore germinates. Some species of microbe, such as Deinococcus radiodurans, can quickly rebuild their genome even if shattered by UV or gamma rays (Lovett, 2006), and the same is true of yeast (Scheifele and Boeke 2008).
Many species of microbe can withstand X-rays and atomic radiation, and are radiation resistant. Therefore, even microbes which are lofted into space by powerful solar winds would likely survive unscathed.
However, not just microbes, but dust and debris would also be cast into space by powerful solar winds. Innumerable microbes could hitch a ride and attach themselves to dust particles. Dust particles are too small to be hit by photons but are the perfect size to reach escape velocity. Although many microbes would die, most might easily survive the conditions of space, protected from radiation by dust and debris (Clayton, 2002; Flanner et al., 1980; Herbst and Klemperer 1973; Nishi et al., 1991; Prasad, and Tarafdar 1983). These microbes need only form spores to survive under these conditions.
If the solar wind was produced by a dying star, interstellar space would be thick with dust which would begin to accumulate in a growing nebular cloud. Once these space-journeying microbes become part of the growing nebular debris field, those deposited in the inner layers of the cloud would be protected against deadly gamma and cosmic rays.
9. Bolide Impact and the Dispersal of Life
Bolide impact is yet another means for life to be dispersed from a single source to other planets, including those in other solar systems.
One need only gaze at the cratered surface of the moon to recognize we live in the midst of a cosmic shooting gallery. Earth has been struck repeatedly by meteors, asteroids and comets (Cellino and Dell'Oro 2009; Elewa and Joseph 2009; Napier 2009; Radice 2009), some with such force that numerous species were wiped out and became extinct (Alvarez 2008; Firestone, 2009; Hagstrum 2009).
Most of these asteroids and meteors have struck the ocean, leaving no physical trace of their impact. However, be it ocean or land mass, bolide impact would ricochet earth and millions of gallons of water into space, along with the creatures living inside, encased, or attached to this debris.
It has been estimated that material from Earth, ranging in weight from a few kilogrammes up to a tonne, and which likely contains living organisms, are dispersed throughout this solar system and beyond (Wallis & Wickramasinghe, 2003). Approximately 150 kg of Earth ejecta are believed to strike Mars each year. This ejecta would necessarily contain microbes and Viruses. Even if most microbes were to die, it has been estimated that at a minimum 7% might survive the journey to another planet (Gladman et al. 1996; Mileikowsky et al. 2000b). Just a few meters of meteorite, asteroid, or comet offers more than sufficient protection for those buried deep inside.
Studies have shown that microbes buried within debris, and as the overlying thickness increases beyond 30 cm, the dose rate and lethal effects of heavy ions, including secondary radiation, depreciates significantly. Even after 25 million years in space, a substantial number of spores would survive if shielded by 2 meters of meteorite (Horneck et al., 2002).
Further, Bacteria and microbes form colonies which serve protective functions. If cast into space, deep inside a mound of earth and stone, those on the outer layers of the colony, if killed, create a protective crust, blocking out and protecting those in the inner layers from radiation or other hazards associated with space travel. Therefore, be they buried within rock, ice, or some other stellar material, and regardless of the depth, colonies of living microbes would provide their own protection with those who die ensuring the survival of those at the center of the colony. In fact, the fossilized remnants of Bacterial colonies have been discovered in a number of meteors, including the Orgeuil, Murchison, and Efremovka meteorites (Hoover 1997; Pflug 1984; Zhmur and Gerasimenko 1999).
Experiments have shown that microbes can easily survive the shock waves of a violent impact and the jerk and sudden accelerations of ejection into space such as might be caused by a meteor strike which ricochets planetary material into the void (Burchell et al. 2004; Burchella et al. 2001; Mastrapaa et al. 2001). A substantial number could also easily survive the descent to the surface of a planet (Burchella et al. 2001; Horneck et al. 2002).
When meteors strike the atmosphere, they are subjected to extremely high temperatures for only a few seconds. If of sufficient size, the interior of the meteor will stay relatively cool, with the surface material acting as a heat shield. Thus the heat does not effect the material uniformly. The interior may never be heated above 100°C (Horneck et al., 2002), whereas spores can survive post shock temperatures of over 250°C. However, as demonstrated by impact studies, if attached to small particles they would gently decellerate when they strike the upper atmosphere and then slowly fall to Earth (Anders 1989). They would not just survive, but begin to multiply.
These same events must occur on terrestrial planets in every solar system in the galaxy. And not just rock and soil, but vast amounts of ocean water would have been been splashed into space, along with all manner of living organisms, all of which would have been instantly frozen. Although multi-cellular Eukaryotes would be killed instantly, numerous species of microbe could form spores. And once this ejecta falls onto other planets, these microbes could go forth and begin exchanging DNA with the denizens of these worlds.
10. Comets
Hoyle and Wickramasinghe (2000), were the first to recognize that comets serves as an ideal stellar mechanisms for the dispersal of life throughout the cosmos (Wickramasinghe et al., 2009). Analysis of spectra has confirmed the presence of organic dust in the tails of comets (Wickramasinghe, 1974; Vanysek and Wickramasinghe, 1975) including dust from Halley’s comet (Wickramasinghe and Allen 1986). In 2006, NASA’s Stardust spacecraft cometary collector, captured particles and cometary gasses from the cometary coma of comet 81P/Wild 2. A wide variety of organic compounds were discovered including amines and amino acids such as glycine (Elsila et al., 2009; Glavin et al. 2008; Sandford et al. 2006). Although a large diversity among comets has been observed, it nevertheless appears that comets, collectively, contain many of the elements and chemical necessary for the creation of life (Wickramasinghe, et al., 2009).
Some comets may have originated as ejecta, that is, from asteroids striking a water world and splashing oceans of water in space. Necessarily, if those oceans contained life, although much of that life would die, a billion trillion microbes and Viruses would survive. Likewise, when comets collide with life-laden planets some fraction of ejected living material would be transfered to other planets and solar systems (Wickramasinghe, et al., 2009). And if these comets contained life, these alien life-forms would then infect that planet with alien life.
11. Rogue Planets and Dying Solar Systems
Prior to supernova, or collapse into a white dwarf, stars will lose between 40% to 80% of their mass during the Red Giant phase (Kalirai, et al. 2007; Liebert et al. 2005; Wachter et al. 2008), with mass both consumed in the star's interior and expelled by increasingly powerful solar winds. Planets and the star they orbit exert gravitational effects on one another (Gladman 2005). Therefore as the star loses mass gravitational influences would be lessened and its planets would significantly increase their orbital distances (Joseph 2009a; Schroder and Smith 2008).
The kinetic energy of an orbiting planet is half the energy of its escape velocity. Planets orbiting a star that loses mass not only increase orbital distance, but may be expelled from the solar system (Joseph 2009a; Schroder and Smith 2008). This suggests that even if the star were to undergo supernova, not all of its planets would be atomized.
In our own solar system the fate of Earth is uncertain. It may increase orbital distance only to be consumed during the Red Giant phase of the sun's death. Or, it may be ejected intact. Naturally, most of the non-microbial life would die. However, life has been discovered miles beneath the earth and below the subfloor of the ocean (Biddle et al., 2008; Chivian et al., 2008; Doerfert et al., 2009; Moser et al., 2005; Gohn et al., 2008; Hinrichs et al., 2006; Sahl et al., 2008). Much of microbial life dwelling deep beneath the surface, would continue to thrive under conditions little different from before ejection; either that, or they would form spores and remain dormant for hundreds of millions of years. Even as the surface of the planet freezes solid, conditions deep beneath the surface would be unchanged, and life would go on as before.
Consider, for example, the bactrium, Desulforudis audaxviator, which lives 2.8-kilometers (1.74 miles) beneath the earth. A genomic analysis of this bacterium revealed that it is "capable of an independent life-style well suited to long-term isolation from the photosphere deep within Earth's crust and offers an example of a natural ecosystem that appears to have its biological component entirely encoded within a single genome (Chivian et al., 2008). If Earth were ejected from this solar system, microbes such as D. audaxviator could easily survive. Indeed, its genome indicates it has never been exposed to sunlight, obtains its nourishment from non-biological sources, and can form spores (Chivian et al., 2008).
Rogue planets that had orbited within the habitable zones of a dying star, could continue to harbor spores, microbes, Viruses, Bacteria, lichens, yeast, and algae even after it is cast from its solar system. These rogue planets might also congregate within the growing nebular clouds formed by the dust and debris ejected by the dying sun's increasingly powerful solar winds. These same winds would have also blown living biomass into space prior to supernova and planetary expulsion. Thus, microbes that had dwelled upon a planet which was later consumed during the Red Giant phase, would have also been blown into the growing nebular cloud. Therefore, rogue planets would not only provide safe harbor for living creatures dwelling deep beneath the surface, but may come to be contaminated by life forms that had been cast into these nebular clouds, including microbes which had been stripped from its own surface.
Eventually, some of these rogue planets would begin to circle proto-stars forming within these nebula, and then become part of these newly forming solar systems (Joseph 2009a; Joseph and Schild 2010). Thus, as new solar systems are formed they acquire planets which do not grow by accretion from particles of dust (Joseph and Schild 2010), but which may already harbored life, and which then grow as debris slams into them. Thus, Earth may have been a rogue planet which had harbored microbes deep beneath its surface even before it became part of this solar system (Joseph 2009a); and this would explain the presence of microbes living nearly 2 miles beneath the surface and whose genomes show no evidence of having been exposed to this sun.
Consider, again, the bacterium, Desulforudis audaxviator, which was discovered 2.8-kilometers (1.74 miles) beneath the surface. A genomic analysis of its 2,157 protein-coding genes indicates this species "is capable of an independent life-style well suited to long-term isolation from the photosphere deep within Earth's crust and offers an example of a natural ecosystem that appears to have its biological component entirely encoded within a single genome" (Chivian et al., 2008).
Rogue planets cast from dying solar systems not only serve to preserve life, but to transfer life, and its genetic heritage, to newly forming solar systems.
If Earth is a remnant of a planet which had been cast from the dying solar system of the parent star which gave birth to our own, is unknown. What is known is Earth was bombarded by mountains of debris for over 700 million years after this solar system began to form. Much of that debris likely contained life (Joseph 2000, 2009a). However, despite the havoc taking place on the surface of Earth during the early stages of solar system formation, life forms living deep beneath the surface would likely survive even as they are subsequently covered by debris. The presence of species miles beneath the surface of our planet suggests they were either deposited there, encased in planetary debris, as the Earth was formed, or they had lived beneath the surface of a rogue planet that was captured by this solar system and which then became Earth.
Therefore, the core of every planet in our solar system may be comprised of the remains of rogue or shattered planets which had been expelled from the solar system of dying stars. These rogue planets, even if shattered, could have harbored spores, microbes, Viruses, Bacteria, lichens, yeast, and algae.
However, only one microbe had to survive, and once on Earth or an Earth-like world, could cover the planet in Bacterial offspring within a few months.
12. Transfer of Life Between Colliding Galaxies: Life is Everywhere
The number of galaxies in the known, Hubble length universe, is frankly unknowable. though if we were to venture a guess, it might be a trillion sextillion. Each of these galaxies contain hundreds of billions to trillions of stars, each of which was presumably fashioned in a nebular cloud (Hartmann et al., 2009; Huff and Stahler, 2006; Muench, et al., 2008; O'Dell et al., 2008). For example, a single galaxy, such as Andromeda, may contain over a trillion stars (Mould, et al., 2008) whereas the Milky Way may have over 4 billion stars. Each of these stars were likely created in nebular clouds which contained all the necessary chemicals and agents for the creation of life (Belloche, 2009; Fraser, 2002; Jura, 2005; Osterbrock and Ferland 2005; Williams, 1998; Zelic, 2002).
Therefore, given a trillion sextillion galaxies with stars which are even more numerous, then chance combinations of all the necessary chemicals to form life, could have taken place in each of these nebular clouds over billions of years of time, such that self-replicating molecules were repeatedly fashioned (Joseph and Schild 2010). However, this does not mean that all would have achieved life. Nevertheless, given even the odds of 1 in a trillion, it can be predicted that life could have arisen in multiple galaxies through chance combinations of the necessary ingredients in the womb of nebular clouds.
Numerous galaxies have been determined to be over 13 billion years old (Pace and Pasquini, 2004; Pasquini et al., 2005). The Milky Way is believed to be 13.6 billion years in age (Pasquini et al., 2005). The life time of a galaxy is unknown, though it is believed they evolve from small dwarf galaxies to spiral or eliptical galaxies over billions of years of time. Fully formed galaxies over 13 billion light years from Earth have been detected In January of 2010, after prolonged observation of Ultra Deep space using the Hubble Wide Field Camera, fully formed galaxies, at distances, from Earth of approximately 13.1 billion light years were reported (American Astronomical Society 2010). If distance is related to time, then these distant galaxies must have been billions of years in age, 13 billion years ago, thus indicating they are well over 15 billion years in age. There are galaxies which are likely even older, which in turn pushes back the ultimate ancestry for life.
Galaxies exchange stars. In fact, some of the stars from the Sagittarius Dwarf Elliptical Galaxy (SDG), which is in a polar orbit around the Milky Way, may have been captured by the Milky Way billions of years ago (Chou, et al., 2009; Majewski et al., 2003). SDG is currently less than 50,000 light years from the central core of this galaxy (Ibata et al., 1997). The Canis Major Dwarf Galaxy (CDG) is even closer (Martin et al., 2004). SDG and CDG are both older galaxies and the Milky Way likely stripped millions of stars from them (Chou, et al., 2009; Martin,et al., 2004; Majewski et al., 2003.
If colliding, merging, and interacting galaxies and their stars and solar systems harbored life, then not just stars, but living organisms would have also been transferred between galaxies. Therefore, even if life had been fashioned only once, in some ancient galaxy which predates our own, the descendants of this life form could have easily journeyed from planet to planet, from solar system to solar system, and from galaxy to galaxy. And if these planets, stars, and galaxies already harbored life, then just as they do on Earth, these life forms would have exchanged DNA and then evolved into sentient animals including those similar to woman and man (Joseph 2000, 2009b,c; Joseph and Schild, 2010).
13. Horizontal Gene Transfer, Viruses, & Evolution From Space
The theory of the "Big Bang" creation event is rife with problems and inconsistencies (Eastman 2010; Joseph 2010; Lerner 1991; Ratcliffe 2010; Van Flandern 2002). Moreover, since first proposed by a Catholic Priest (Lemaître 1927, 1931a,b), the "Big Bang" birth date has been steadily moved backward in time from 2 billion to 8 billion to 13.8 billion year ago (Lerner 1991; Van Flandern 2002). As the ability to detect distant galaxies increases, it can be expected that the acolytes of the Big Bang will continue to move this hypothetical creation event back, back, and further back in time.
The fact is: the age of the universe is unknown, though numerous theories abound. It is the position of this author that the universe is infinite and eternal, and has no beginning, and, no end (Joseph, 2000, 2010). In an infinite universe there is no creator, no god, and life has had infinite time to achieve life and to evolve.
However, let us ignore for the moment, the reality of an infinite universe and the likelihood that life can hitchhike from galaxy to galaxy, and instead restrict the origin of life to a single source in this galaxy and explore the implications. If life began its journey toward life, 13.6 bya with the establishment of the Milky Way, and by 10 bya the variable descendants of that life had taken up residence on at least some habitable planets orbiting in the habitable zone, it can be predicted that life, and its genome, would have evolved, and genes would have been transferred between variable life forms--just as they are on Earth. Using our planet as an example, these life forms would have also biologically altered their environments as they consumed minerals, metals, gasses, and chemicals and synthesized and excreted byproducts. Therefore, just as Earth evolved secondary to biological activity (Joseph 2009b,c), the atmospheres and oceans of other planets would have also been altered. And just as the altered environment acts on gene selection, expression, and inhibition (Joseph 2000, 2009b,c) thereby modulating the evolution of increasingly complex species on this planet, the same gene-environmental interactions would be expected to take place on other worlds.
Further, using Earth as an example, just as microbes and Eukaryotes have synthesized and secreted all manner of byproducts, including oxygen and calcium, which in turn acted on gene selection, promoting the evolution of oxygen-breathing creatures equipped with bones and brains (Joseph 2009b), we can predict that on Earth-like planets, life with bones and brain would have also evolved.
Initially, soon after life was first formed evolution on other planets might have been shaped by means of "natural selection" and random environmental-genetic interactions. For example, bacteria, archae, and viruses may have mutually exchanged genes, thereby fashioning a Eukaryote with a genome of active and silent genes. As the environment changes secondary to biological activity and natural forces, some of these silent genes might have been expressed giving rise to new species. It can also be predicted that initially a variety of genetic experiments in evolutiontook place, on thousands, millions, and maybe billions of Earth-like planets, long before the birth of our solar system. Therefore, subsequent extra-terrestrial experiments in evolution would have also been shaped by the acquisition of new genes subsequently inserted by Viruses, Archae, and Bacteria periodically deposited on those planets via mechanisms of panspermia. Some of these genes would be passed down vertically, and then expressed randomly or secondary to environmental or genetic triggers. Due to natural selection alone, increasingly complex and intelligent species would evolve and inferior competitors would become extinct.
If we ignore the reality of an infinite universe, and pick a hypothetical birth date of 13.6 bya for the beginning of life, and using the evolution of life on Earth as an example, then it could also be predicted that sentient, intelligent life would have evolved on numerous Earth-life planets by 9 bya. This could mean that the genetic template for the evolution of all manner of life, including those similar to humans, would have been established almost 5 billion years before Earth became Earth.
In an infinite universe, these initial experiments in evolution would have taken place infinite times and infinitely long ago. Even if we accept a hypothetical Big Bang creation event, and given that the birth date is merely conjecture, then these initial evolutionary experiments could have taken place 15 bya, 20 bya, 100 bya, and so on.
Be it an infinite universe of a Big Bang, as microbes and Viruses were cast from world to world, they would not merely carry genes, but would have exchanged genes with the denizens of these other planets including their fellow travelers. Genes would be exchanged via horizontal gene transfer utilizing the same genetic mechanisms of exchange which are common among the microbes and Viruses of Earth. These space-journeying microbes and Viruses would have also exchanged and obtained genes from Eukaryotes on innumerable planets and would have continued to build up vast genetic libraries of genes coding for advanced and complex characteristics, and those shaped by natural selection.
Eventually these microbes, Viruses, and their vast genetic libraries, fell to new Earth. And the genetic libraries maintained in the genomes of these Viruses and prokaryotes, made it possible to not only immediately adapt to every conceivable environment, but to biologically modify and terraform new Earth, and in so doing, they began to promote the evolution and replication of species which had evolved on other worlds (Joseph 2000, 2009b,c).
Almost all scientists will agree that modern day life can trace its genetic ancestry to the first life forms to appear on Earth. These first Earthlings (Archae, Bacteria, and their viral genetic luggage) contained the genes and genetic information for altering the environment, the "evolution" of multicellular Eukaryotes, and the metamorphosis of all subsequent species (Joseph 2009b,c).
Genes transferred to the eukaryotic genome by prokaryotes and Viruses, include exons, introns, transposable elements, informational and operational genes, RNA, ribozomes, mitochondria, and the core genetic machinery for translating, expressing, and repeatedly duplicating genes and the entire genome (Charlebois and Doolittle 2004; Dehal and Boore 2005; Harris et al. 2003; Koonin et al. 2004; Koonin and Wolf 2008; Lynch and Conery 2000; Lynch et al. 2001; McLysaght et al. 2002). Archae, Bacteria, and Viruses, provided Eukaryotes with the regulatory elements which control gene expression and which have repeatedly duplicated individual genes and the entire genome thereby enabling the Eukaryote gene pool to grow in size and leading to evolutionary innovation and the generation of new species.
Viruses maintain a large reservoir of excess genes, and viral bacteriophages commonly invade Bacteria and transfer genes which improve the functioning of the host (Sullivan et al., 2006; Williamson et al., 2008). Yet others provide genes to Eukaryotes (López-Sánchez et al., 2005; Romano et al., 2007). Thus, the eukaryotic genome, including that of humans, not only contains DNA inserted by prokaryotes, but genes inserted by Viruses (Conley et al., 1998; López-Sánchez et al., 2005; Romano et al., 2007). Viruses have directly impacted eukaryotic evolution. Moreover, once these viral genes are incorporated into the host genome, they can be transmitted, in "silent" non-acted form, to daughter cells, only to be expressed in response to specific environmental signals (Ackermann et al., 1987; Brussow et al., 2004).
Viruses, as well as Bacteria and Archae, can store their genes within the eukaryotic genome (Conley et al., 1998; López-Sánchez et al., 2005; Romano et al., 2007). In fact 8% of the human genome consists of around 200,000 endogenous retroviruses (IHGSC 2001; Medstrand et al., 2002), and 3 million retro elements (Medstrand et al., 2002), and some of these retroviruses are still active (Conley et al., 1998; Medstrand and Mager, 1998).
When a Virus invades a single celled organism, it may donate its genes which become incorporated into the genome of the host. In some instances, when Viruses invade Eukaryotes, they may sicken the host and the Virus eventually dies. In many respects, it could be said that these Viruses introduce errors into the genetic hardware of the host. Yet other Viruses (endogenous retro-Viruses) provide substantial benefits to the host and are often subverted by the host for its benefit (Lorenc and Makalowski. 2003; Miller et al., 1999; Parseval and Heidmann 2005). For example, endogenous retro-viruses (ERVs) are responsible for the generation of proteins involved in the formation of placenta (Mi et al., 2000; Blond et al., 2000). ERVs promote cell fusion (Mi et al. 2000, Blaise et al. 2003) and provide a protective function, allowing for nutrients to pass from mother to fetus while simultaneously protecting the fetus against infection or rejection by the mother's immune system (Ponferrada et al., 2003; Prudhomme et al., 2005). ERVs are also highly expressed in many human fetal tissues including heart, liver, adrenal cortex, kidney, the central nervous system, and human brain (Anderson et al., 2002; Patzke et al., 2002 ; Wang-Johanning et al., 2001, 2003). Viral genes play a significant role in the generation and metabolism of nerve tissues and the developing brain (Andersson et al., 2002; Conley et al., 2008; Seifarth et al., 2005).
ERVs are very active in the human genome (Lower et al., 1993; Medstrand P, Mager DL. 1998). They regulate human gene expression (Jordan et al., 2003; van de Lagemaat et al., 2003) and contribute promoter sequences that can initiate transcription of adjacent human genes (Conley et al., 2008). Endogenous retroViruses, therefore, can alter host gene function and genome structure and thus the evolution of eukaryotic hosts including humans. Thus we see for example, that human evolution has been shaped by successive waves of viral invasion (Sverdlov, 2000).
However, because Viruses target specific hosts, innumerable Viruses cannot inject their genes into that host until after that host evolves. Or genes inserted into the germline only become activated after that host evolves. For example, the genomes of specific endogenous retroviruses were inserted into the primate genome tens of millions of years ago, and then activated or silenced at key points of evolutionary divergence, such as the split between new world and old world monkeys, and the split between hominids and chimpanzees (López-Sánchez et al., 2005; Romano et al., 2007). Presumably, these viral genes triggered species divergence and promoted the evolutionary progression leading to humans.
Retroelements encompass 42.2% of the human genome and almost half of the mammalian genome (Deininger and Batzer 2002; van de Lagemaat et al. 2003). The human genome contains 200,000 copies of endogenous retroviruses grouped in three classes (Lander et al. 2001), which have been introduced through at least 31 infection events (Belshaw et al. 2005); each infection event however, required that the host first evolve, and previous infectious events are associated with the evolution of a host which was then targeted by other Viruses. Thus, viral genes have accumulated in those genomes leading to humans. Coupled with the 158,000 mammalian retrotransposons inherited from common ancestors, ERVs make up 8% of the human genome (IHGSC 2001). Retroviral sequences encode tens-of-thousands of active promoters and thus regulate human transcription on a large scale (Conley et al., 2008). However, these percentages are only gross underestimates.
Therefore, Viruses not only provide prokaryotes with genes but Eukaryotes with genes, and this genetic endowment had directly impacted evolution leading to the metamorphosis of humans and the human genome.
14. The Evolution and Metamorphosis of Life From Other Planets
The defining feature of Viruses including retroviruses, is they precisely target specific species and host cells. Further, the viral RNA genome is actually a template for DNA which must have been copied from another source of DNA. This explains why the Virus acts purposefully, targeting and inserting its RNA or DNA into specific hosts where there is a perfect genetic match, and why errors are introduced if the match is not perfect. The ease at insertion and integration, the fact that the viral gene-host genome are a perfect fit, indicates that the original viral source for this RNA/DNA template of DNA was the DNA of an extra-terrestrial host genetically identical to the targeted host which evolved on Earth. As these viral agents must have existed prior to the evolution of their Earthly hosts, then they must have obtained these RNA DNA-templates from identical hosts which must have existed on other planets. This would explain not just the perfect Virus-host match and the ease of viral DNA insertion into specific hosts after they evolve, but the fact that these inserted genes often interact smoothly with a network of host genes, often to benefit the host, and act to purposefully increase and promote speciation and evolution.
However, although over 40% of the human genome consists of genes inserted by Viruses, including genes coding for the human brain, much of the remainder of the human genome can be traced to genes inserted by Archae and Bacteria (Joseph 2009b,c). Thus, evolution leading to humans, has been guided by genes inserted by microbes and Viruses whose own ancestry can be traced to life forms which journeyed here from other planets. This indicates that similar genetic interactions leading to similar evolutionary progressions must have taken place on other planets.
An analysis of the microbe, viral, and eukaryotic genome and the evolutionary progression which has taken place on this biologically engineered planet leads to this conclusion: The first viruses and life forms to arrive on Earth contained the genetic instructions for creating all of life, and some of these genes were transferred to or gave rise to the eukaryotic genome. Just as an apple seed contains the genetic instructions for the development of an apple tree, these genetic seeds of life contained the genetic instructions for the tree of life, and for every creature which has walked, crawled, swam, or slithered across the Earth. Genes act on the environment, and the biologically altered environment acts on gene selection, thereby expressing traits which had been encoded into genes acquired from life on other planets.
Evolution on Earth could be likened to metamorphosis and embryology. Metamorphosis is genetically regulated. All aspects of development are guided and controlled by genetic-environmental interactions. Embryogenesis is under genetic control. Why should evolution be any different? However, rather than 9 months, or a single season, it takes billions of years to grow a human from a single cell.
What has been called "evolution" is under genetic regulatory control, in coordination with the biological activity of innumerable life forms which genetically engineer the environment. Genes act on genes, genes act on the environment, and the altered environment acts on gene selection, thereby giving rise to an evolutionary progression from simple cell to sentient intelligent being, each evolving into a world which has been genetically prepared for them. What has taken place on Earth represents not a random evolution, but the metamorphosis and replication of living creatures which long ago lived on other planets.
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