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Live and the Living beyond space and time

2009 г.

Rey L.

One day, Life was born…
   No other notion, maybe no other concept, looks more familiar to our eyes than Life. Universal, unique in its nature, but polymorphous in its representations, essentially fluid, but at the same time quite stable, Life is altogether identity and diversity, stability and evolution. In the middle of a physical universe of frozen structures on man’s scale, the living world displays a fascinating show, continuously renewed, of independent beings, nevertheless united within a coherent and binding system where predetermined rules do not exclude free enterprise and where all things evolve continuously by a constant adaptation to environmental constraints as well as in function of their own internal evolutionary thrusts.
   Indeed, this long conquest of the “mineral” by the “organic” is a very slow process which has taken place in the course of the 3 billion years during which the biosphere did build up out of the imprecise mists where, one day, appeared this little star with a cold skin which bears our destiny in the vast expanses of the cosmos.
   Life, for long, remained hidden in the realm of micro-organisms, itself enshrined in the protective cradle of the oceans. However, under this primitive envelope, it already showed its fantastic capacities of resistance and adaptation. Reproducing themselves from generation to generation in the strict respect of their hereditary patrimony, the first living beings remained, nevertheless, under the continuous pressure of selective forces which, by a long sequence of adapted mutations, gave rise to given genetic combinations demonstrating better chances of survival and development. Thus, progressively, the original genome, did evolve by successive touches, thanks to the hazards of lucky genetic recombinations or else by incorporation of foreign genes transferred by viruses, building a new world of infinite potentialities. On the common matrix of nucleo-proteins, life has built its glittering arabesques since millions of years and up to the most recent times of our human adventure, nothing has ever been able to alter its fecundity.
   Out of this subtle game between living beings and their environment, and all along the geological times, appeared hundreds of thousand, then millions of different species of rising complexity in which, isolated cells, autonomous at the start, grouped together in organic structures with wide interconnections, spreading from the bottom of the seas to the whole world : a stunning and fascinating history, made out of hazard and necessity, of individuality and diversity, of free enterprise and of hierarchy. Life, a common matrix for all living beings, life which is always transferred and never created from nil, life is the most intriguing of all the mysteries of our world, a unique enterprise which nothing could ever forecast and which blooms in one single shot or else does not exist.

   Active Life – Latent Life
   How, then, could we avoid to question ourselves upon these mysterious lands which sever and nevertheless unite, actual life, latent life or suspended animation from these forbidden areas which, beyond terminal states, drive us to the frontiers of death ?
   Life is action but we, equally, know, since a long time, that, in the vegetal realm, we can find periods of deep physiological rest which are basically needed for the preservation and dissemination of the species. Then, as spores, pollen or seeds, the living matter manages to place itself outside of the time-scale and the dehydrated cells may remain for centuries, even millennia, without any noticeable metabolic activity.
   This phenomenon is not specific to the vegetal reign and we have observed, since Leeuwenhoek, 250 years ago, that certain small animals can remain “out of time” for decennias after dehydration. Deprived of their driving force, water, they can challenge centuries such as the rotifers present in the collections of the “Museum of National History” in Paris.
   Are we allowed to deduct from these observations that, within these dehydrated organisms, all life has disappeared ? Actually, no, since, even when almost completely dry, these living beings do show a very small metabolic activity, definitely at the limit of our experimental tools, but, nevertheless real. No, also, because, if we add back the water which has been extracted, these organisms are able to recover almost immediately their former dynamics. We should admit, therefore, that they were placed under ’suspended animation’ and it might very well be that it is under that form that Life appeared on Earth.

   Extra-Terrestrial Life and Lithopanspermia
   Our planet moves at high speed in space together with a multitude of celestial bodies among which, some of them, of small size, are from time to time entering the earth gravity field and, eventually, penetrate the atmosphere. They become incandescent and, generally, end up their course into the depths of the oceans or hit the continents digging sometimes enormous craters. These are the so-called meteorites that we can witness as luminous tracks in the dark sky of our summer nights.
   Most of them, of course, disappear totally, lost within oceanic expanses or spread out on continental lands but there are, nevertheless, some privileged areas where they might be recovered. This is the case of sub-tropical desertic lands and, essentially, of the 11.000.000 km2 of the icy Antarctic dome. In this last place, some of them, sometimes only of a mm size, penetrate the snow cover, embed themselves into ice and remain there, intact for millennia. They are, definitely, the only recoverable samples of the 50.000 tons of spatial dust which are believed to fall on earth each year.
   Recent analyses done in the light of the advanced knowledge acquired through space research, seem to demonstrate that some of these “celestial stones” come from the planets of our solar system, most essentially from the Moon and from Mars. Indeed, the lunar origin of sample ALHA 81005 has been confirmed with certitude, as well as for six out of nine meteorites discovered in Mounts Yamato in Antarctica. It even looks quite certain that sample ALH 84001 is coming from Mars. The conditions under which these stones have been “extracted” from their respective planets are well understood : a brutal expulsion in outer space from the planet ground subsequent to the fall of a large meteorite, opening a vast crater ; this is particularly true for the Moon which is not protected by an atmosphere. Indeed, the meteorite impact on the planet is so violent that fragments of rock are shot away at speeds high enough to escape the local gravity field, 2.4 km/sec. and 5 km/sec. for Mars. Then, in the vast outer space of our galaxy, these “sampled-stones” are bound to travel at very high speeds for thousands, hundreds of thousand and most probably millions of years! until one day, they come close to the earth, are captured by the gravity field and eventually fall to the surface at speeds close to 10 – 30 km/sec. becoming incandescent bullets when they hit the ground.
   On another side, a detailed survey of Mars has shown, without any doubt, that we can still find there large amounts of water, sometimes deep inside or as vast polar ice-domes. Moreover,the chemical composition of the ground rocks, as well as the gas contents of the Martian atmosphere, drive us to think that, million years ago, life could have been present on Mars. Furthermore, the microscopic examination of the Martian meteorites found in Antarctica, shows structures which are very similar to those of terrestrial micro organisms. This leads us to believe, that at the onset of earthly geological times, its sterile spaces might have been seeded from planetary dust coming from outer space which might, thus, be considered as an infinite storage area of potential life in suspended animation. This is the theoretical basis of lithopanspermie.
   However, even if we admit the existence of these “mobile space life germs”, is it still reasonable to agree that they still have the power to generate life after such a long holding time in outer space and having been submitted to such a formidable mechanical and thermal stress during their penetration of the earth atmosphere ?
   Curiously enough, it is, at a hundred year interval, that we have been able to answer these two questions and both answers are positive.
   In 1880, the US Army Medical Corps Surgeon Lagarde did spread revolver bullets with Bacillus anthracis and did show that, when the bug was under its sporulated form, it could withstand the fire of a Colt 38 surviving both a temperature over 100°C at the outlet of the barrel and the shock of the bullet on a steel plate positioned only 4 meters away. Almost identical experiments done in 1885 in Bern, Switzerland, by physicist Nadeschda Pustoschkin, did confirm that micro organisms could resist being fired from a gun.
   It is also pretty clear that, should sporulated micro-organisms under suspended animation, be present within the meteorites, the penetration of the earth atmosphere might not be as drastic as we could expect. The rocks crossing the air mass at high speed will only be heated on their periphery and might not be destroyed at impact if they fall in the ocean. However, can we assume that, after such a long travel in outer space, these micro-organisms are still susceptible to seed life? On a pure theoretical standpoint, the answer is yes because it is quite certain that, in the high vacuum of outer space, these micro-organisms are definitely under the freeze-dried / lyophilized form. We know quite well that this particular process is used precisely to store for very long periods delicate biologicals and living viruses and bacterias. Moreover, the micro-organisms which are inside the meteorite are also, in outer space, protected from the dangerous u.v. solar radiations.
   However, can we equally consider that they do keep their life potential for such long periods of time?
   The answer, once more again, is yes and a rather recent communication made in SCIENCE in 1995 by Cano and Borucki shows that bacterial spores sampled in a piece of amber, 40 million years old, could be “resuscitated”, grown on conventional media and identified. We can, then, deduct that it is not unthinkable that life has been spread out in the solar system by freeze-dried micro organisms, travelling on “rocks-back”, soon after the individualisation of the planets. Even more, some present research work done in Lausanne University, let us believe that Earth has not been the first site to be “colonized” by life. Indeed, the oldest samples of micro-organisms we can find in the earth geological layers are photosynthetic cyanobacterias, actually rather advanced prokaryotes, the ancestors of which should have been in existence for at least 10 billion years if we agree that the mutagenesis rate has remained constant. Since it is known that the solidification of the earth crust did occur only some 3.9 to 4 billion years ago, life could have been brought there, roughly 1 billion years later, by seeding from outer space with bacterias coming from more advanced planets!
   It is, thus, reasonable to consider that lithopanspermia is not a mere theoretical dream. It can even foster more audacious thinking: outer space becoming a repository of living matter, pushed away in the galaxy by the solar wind, stratospheric clouds and the comets turned into cosmic fermenters! Quite sincerely, there is a provocative dimension in all these considerations but we have learned to know that we need to be very cautious before eradicating new ideas since we do have many examples of recent developments which were considered as pure fancy a century ago and which, today, are well established on hard solid grounds. Is this not true for genetic engineering?

   Life, Cold and Time
   If the mechanisms which govern suspended animation of dehydrated organisms are rather clear, it is quite another issue when water is extracted by low temperature freezing. Experimental work carried in that direction in the mid 50’s has, indeed, shown that it is possible to cool down living cells to the lowest temperatures that can offer cryogeny without destroying their life potential. In our laboratory we discovered in 1956 that a chick embryo heart could be frozen hard to -196°C (liquid nitrogen) after prior treatment with glycerol, kept frozen for months and that it could recover its original physiological beats after rewarming. Since that period, this type of research has been extended to endocrine glands, epithelia and even whole embryos, laying the basis of the well known organ and tissue banks.
   Is it still possible to speak of “suspended animation” in those frozen tissues? It looks as if we should answer no since, this time, even the more sophisticated investigation techniques cannot detect any sign of metabolic activity in those vitrified tissues. At first look, all trace of life has disappeared. Actually, how could it be otherwise when, in the process of freezing, all the cellular equilibria are ruptured and physiological mechanisms progressively blocked into organised rigid structures. Evolution turns into stability, reticular rigidity replaces plastic movements: life crystallizes out into inert flakes! Sure, within this petrified universe we can still detect those physical turbulences which run throughout the mineral world: atomic oscillations, molecular vibrations are present into the hardened tissues and contribute to the primitive conscience which imbues mineral solids. However, when we reach the vicinity of the absolute zero the solid itself enters a state of complete inertia in which the frozen living matter may remain unchanged for times immemorial.
   We meet, here, new concepts which are quite outside our conventional thinking : Immutability and the Indefinite..
   Immutability represents a “permanent” state: a state which remains identical to itself as time flows by. As such, it is almost impossible for our brain to understand what it means since any intellectual perception implies a participation of our mind to the evolution of the material under investigation. Indeed,we cannot sever any object from its time frame!
   Even more difficult to conceptualize is the notion of ‘ indefinite’. Indeed, a living being, a structure, might appear motionless during the time of our observation, however, as soon as we speed up time, the masked movements appear and nothing escapes that rule. Mountains and continents, at geological time scale, surge or disappear deploying a gigantic foam on the earth crust. Similarly, at the sidereal scale, planets and galaxies enter into an infernal maelström where new worlds burst apart whilst only a lonely, icy light still recalls the existence of isolated stars which fade away millions of years ago.
   At the absolute zero, to the contrary, entropy is nil. Everything lies in permanent order: it looks as if the “matter” itself is dead and cannot do otherwise than remain as such, indefinitely. Time has lost its power to make it evolve and, under those conditions, the living systems, turned into crystalline bodies, escape the normal fate of the Cosmos and enter into some kind of eternity. Is it still conceivable, then, to speak of “suspended animation” since the frozen tissues are, indeed, lying ‘out of time’? Is it still possible to speak of “life” since, in that particular state, the absolute zero, the “mineralised” cells do not “exist” any more but are a mere condensation of inert matter unable to be analysed ? Actually, we are in a situation which is close to the famous ‘uncertainties’ described by Heisenberg. As it is not possible to get, simultaneously with the same precision, the position and the cinetic energy of a particle, any attempt to examine the frozen tissues at the absolute zero is bound to be impossible, since their observation would bring enough energy to drag them out of their permanent state and make them again time sensitive.
   Immutable and eternal, the frozen living matter at the absolute zero appears mysterious. It “is” but does not “exist”. Inside, the former life has been brought to a permanent neutral state ’out of time’: it is a mere phantomatic material which, at that state, has lost the dignity of existence but, nevertheless, has kept all its potentialities. Indeed, should we change the thermal conditions and start rewarming the frozen tissues, we can observe anew the dynamics which drive the living organisms and they start to “be” again. At the end of this prolonged period of anabiosis, life flows back into the melting solid. This is an unbelievable situation since we do not know how life has been able to “survive” in these hardened bodies. By which mechanisms had this essentially moving entity been able to remain intact into this petrified matter? Can we assume that, when “life” severed itself from “the living”, in the course of freezing, it left into the material a powerful imprint which bears its signature? Is it some kind of an “a priori living form” as it could have been said by Emmanuel Kant? Can it be compared to memory which does remain recorded within the neurons of the intricate network of our cortex and “survives” the flash of thinking? Do we really have, in the frozen tissues a “potential life” which bears the heritage of a former “existential life”?
   This is, definitely, a challenging issue since we are compelled to admit that not only the delicate dynamism of the living has vanished but that, maybe, life itself has really disappeared and merely left in the frozen cells the stern inert imprint of its former driving force ! An inert state, yes, but how powerful since by simple rewarming it can “”regenerate” active life again.
   We can, thus, assume that, under those circumstances, what we witness, during the heating period, is not a mere restoration of life but, maybe, the genesis of a new life ! Then, in the course of this rewarming phase, we might be able to observe, within a limited temperature span of 200°C, the flow-sheet of this long phylogenic evolution which, for billions of years, has seen the biosphere bloom out of the mineral world. Every individual step in this process has thus its own significance and presents an ontological character, this whole evolution being, in fact, a condensed spectrum of the apparition of life itself on earth.
   When we deal with mammalian cells and organs, should we not consider, then, that, under the powerful move which “sublimes” the mineral world, we can follow the progressive development of this “biological sheet” which, according Teilhard de Chardin, lines, point by point, the material fabrics of the Universe?
   Could we not imagine further that, thanks to the controlled use of very low temperatures, we might be able to see, one day, how mind and soul progressively sweep into the moving matrix of the living and unveil, there, the supreme immaterial principle of all things: the presence of God?

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