Man lives on the earth, and although his Kingdom is not of this world, this seems insufficient reason to neglect our relation with our foster planet, which has been, and probably will remain, the sole abode of mankind. As Henderson (1913) pointed out in his masterly essay The Fitness of the Environment,1 current opinion, up to the birth of natural sciences was that the earth was created as our playground, our property, and that all conditions on earth, physical, chemical and biological, were such as to create the best possible of recreation parks of Homo sapiens. If this were so, we have cut a rather sorry figure in maintaining this park. Vandals, rotten and wasted, rather than stewards and managers we have been, dissipating this part of our divine heritage at an ever increasing rate.
The dawn of our understanding of geobiology, the relation of living things to the earth, is therefore merely anthropocentric and this is not to be wondered at, as the old religion books, such as Genesis, were conceived and inspired when man already began to shape the face of the earth when the anthropic epoch had as a toy set in.2 And this ancient, pre-scientific mode of thinking is still paramount in many people, in folklore not only, but still in living thought. We divide the hood-fungi into “toadstool” (poisonous) and “mushroom” (edible), we speak of “noxious” and “useful” animals, of “weeds”, “herbs” and “flowers”. An organism should have a “virtue”, apart from its bare existence!
I have not been able to cull from the Greek philosophers’ dicta about matters geobiological, but remember the saying of Aristotle, “Man is, by fate, the best-known animal”. The best known [animal] of Aristotle is the unknown [animal] of Carrel (1935)!3 The best known in its taboos, in its nicknames, in its head, in its greed. The unknown [animal] influences however, the unexploited force to their good!
When man began to look around and to recognise objects, it was already late in the day, let us say 17th or 18th century. About 1542 we find Van Helmont,4 who proved that a willow tree forms itself chiefly out of water and air, then, in the 18th [century] we find Linné who recognised the biological lime deposits (omne calx ex vivo!),5 and later, in 1779, Jan Ingenhousz published his Experiments Upon Vegetables in which he proved that green plants, under the influence of sunlight, “improve” the quality of the atmosphere, or as he said “dephlogistonate”.6 Lyell expressed his actuality principles in geology.7 And the concept of evolution increasingly occupied the mind, foregoing a lasting link between geology and biology. Then, by the genius of Pasteur, the universal distribution of microbes through the air was recognised (1860).8 The sciences of microbiology, grown and tended by Pasteur’s loving hands, developed to a great science under his followers Winogradsky and Beijerinck.9 “L’influence des êtres infiniment petits paraît infiniment grande”, says Pasteur. Physiology of plants and of animals, biochemistry and genetics define the position of living things in the general scheme of this world.
Now, in the nineties, there stand recorded an experiment of Martinus Willem Beijerinck, which gave the clue and the key to a great biological problem, that of distribution and that of dispersal. Already in 1842 Goodsir had observed, in the stomach of a person suffering from gastric ulcer, a so called packet bacterium Sarcina, which he called Sarcinaventriculi. Beijerinck isolated the same Sarcina, more than fifty years later from ditch water. This on itself is not so remarkable as the method of thought underlying this experiment. Beijerinck created, one by one, in his culture vessel, the conditions, the “milieu factors” characteristic of a mammalian stomach, to writ 1) anaerobic, 2) high acidity, 3) 37 °C, 4) high concentration of organic substrata.
Beijerinck has asked a definite question. Which organism resonates with the given environment? Which organism, amongst the thousands of various latent spores and germs, will show itself and multiply as a counter world of the culture solution provided. In this experiment, like in a huge number of other isolations performed by this great biologist, these are underlying thoughts, as I said, of the greatest importance. The first is the conviction that all species of microbes occur everywhere and the second is that, although these microbes are everywhere a specific milieu will select a specific organism from the large mass of latent life. These rules, to which I have given the name of Beijerinck’s rules, may be briefly (although not quite correctly) summarised as “Everything is everywhere and the milieu selects”.10
Let us name another experiment of Beijerinck. A slice of white bread is put under the steady trickle of a tap, not directly under the tap, but so that the “splash” wets the bread. After a week or so at room temperature a beautiful violet bacterium, B. violaceum develops (Derx, oral communication).11 Still another example; a mineral agar is prepared and poured into a plate. Care is taken to omit nitrogen compounds. The plate is inoculated with garden soil suspension and placed in the light. Bluegreen algae develop, that need light for development, but are able to fix atmospheric nitrogen! The numbers of examples are legion. The whole process of enrichment cultures is based upon Beijerinck’s rules (see also Stockhausen).12
The universal dispersal of organisms is of the greatest importance to geochemistry, a fact already recognised by Charles Darwin. Geobiology deals with the interplay of forces; animate and inanimate. Strictly speaking, it should include the history of mankind as well, as far as it is concerned with the shaping of the earth. It is difficult, in the drama of geobiology, to separate the stage from the actors. Still more difficult it is to tell the hero from the villain. Maybe there are no heroes and no villains. The stage of the drama we shall call the milieu, and the actors, the living beings, are driven by their environment and by their inner; say, by nurture and by nature, by “nourriture et nature”. Their environment is part animate and part inanimate. In order to evaluate their influences, a great many data were needed. Geochemistry as a separate discipline came into being in this century (Vernadsky, Day, Clarke, Goldschmidt).13 The concept of milieu, initiated by Yves Delage14 and by Claude Bernard,15 has been much more clearly defined in the last decades. The mutual relation of organisms has been better understood since the discovery and ever increasing knowledge of vitamins, hormones and other ergones.16 Geology, almost grudgingly is given an increasing amount of room in the textbooks to topics biological (outside Foraminifera and other fossils), although, even in recent books, one meets many biological heresies.
The role of the atmosphere in the dispersal of living matter, already recognised by Pasteur, has been, in recent years, repeatedly investigated. Water analysis, since the publication of the data of geochemistry, has founded new paths. We are justified in saying that it seems not too premature to endeavour to link up the data obtained from several fields and try to form a synthetic picture, which we might call geobiology. As this geobiology is written by a biologist, there is a decided bias to the biological side. The author offers no apology for this tendency. The discipline described here as the crossroad leading to a great many sciences, and although many seductive paths lead into one or the other realm, it seemed safer to keep to the biological highway. And when the writer has strayed, it was to return to this highway with the conviction that the key to geobiology lies in biology itself.
[Ecology] literally the knowledge of the oikos, of the house. The house being the earth. Actually, it describes the relation of land organisms to this environment. Ecology in the broadest sense embraces at least eight sub-divisions (Table 1.1), to wit:
1.2.1.a Ecology in the strictest sense
Ecology. [Ecology] deals with terrestrial organisms (Elton, Clements, MacDougall, Cooper).17 It is concerned with the adaptation to certain environments, with the character of vegetation and forma in these environments, without further query into their causes. In the botanical ecology we recognise for instance hydrophytes, plants growing in a humid atmosphere and their opposites xerophytes, plants growing in a dry environment. Then there is the great group halophytes, salt-loving or salt-tolerant plants, also the rheophytes, plants growing on very steep inclines. Finally, epiphytes, plants growing upon other plants. In animal ecology we might create a similar series.
This section should of course be very much extended. Having for the epiphytes the recent monograph of Went,18 for the halophytes Ruhland and Montfort,19 for the xerophytes Walter20 for the hydrophytes Glück, Troll, Shelford.21
Synecology, vegetation types and groups. Schools of Blytt-Sernander22 and of Braun-Blanquet.23 Plants and animals occurring together have formed the object of much literature which is, as far as I can see, chiefly nomenclatorial. As long as this branch of ecology remains in that state many of us seem to be totally unimpressed to it. A word for instance is Carpinion-Betuletum, but neither Carpinus nor Betula need to occur there.24 Synecology when viewed from the point of view of symbiosis (Funke) may be very useful,25 but that facts and experiments should take the place of mere verbosity. It appears that Braun-Blanquet from Montpellier goes the furthest in thorough division of vegetation types.
Biogeography. Apart from its use in distribution the “area” concept has been developed, usually in combination with geological speculation (Wegener, Vening Meinesz, Holmes).26 Biogeography has been of great service in phylogeny, in geomorphology and in the part of ecology that deals with the distribution of organisms. Alexander von Humboldt initiated this science in the beginning of the 19th century.27 It has been part of ecology from the very beginning, especially after the appearance of the treatises by Schimper28 and by Warming.29 The original concept of the relation between climate and vegetation type, a purely ecological concept, is certainly von Humboldt’s.
1.2.1.b Soil science s.l. [in the broadest sense]
(Russell, Waksman, Tolman).30 Soil is facies of weathered, often sedimentary rock with specific chemical and physical properties, which make it fit for the rock milieu of terrestrial plants.
Microclimatology. Ecologically the atmosphere in contact with the soil belongs to soil science. As official meteorology starts at the 6 ft level, the intricate, microclimatological changes are lost to meteorologists. Microclimatology deals with the climate in very small areas, with inclusion evaporation, wind velocity, temperature, humidity etc. and their gradients in and near the soil (Pinkhof).31 Here we find heterogeneity and extreme values, but values of primary importance to the vegetation. The same cannot be said of the official weather report data.
Pedogenesis.32 This is part of ecology (Correns, 1939) but for the organic part;33 the humus. The origin of humus (Waksman) is one of the most important parts of pedogenesis. We mention, furthermore, such problems as poor exchange, grain size and its distribution, pedolisation and lateralisation.34 By description of these phenomena a natural classification of soils results. The problem of synthetic soil has as far as I am aware not been sufficiently attacked. The author can find no word to describe the biological counterpart of this purely non-biological microclimatology and petrogenesis.
Agrogeology is certainly not right, because he (= Correns, 1939) wants to embrace all types of soils. The bacteriology and geobiology of plant and animal should be dealt with here. It seems a wonderful chance for somebody to systematise the enormous mass of data on the subject already existent.
(Founded by Forel, the classic is named “Le Leman”).35 The biological part we shall call hydrobiology, the environmental part limnology, occurring in water in ecological classes. The biological part first classifies types of organisms:
a. Higher aquatic, floating, or rooted in the soil. In the latter case we meet with the problem of oxygen transport (Roodenburg for Nymphaea, Van Raalte for Oryza).36 Glück has given a biological description of higher plants.37
b. Plankton. The more or less floating microscopic animals and plants, show a world of special biological characteristics. They influence the water to a high degree, they are influenced by the water equally markedly, diversity, light transmission and the physical factors play a large role here. Plankton, in many cases may also enrich water with certain (not all minimum) compounds (Wesenberg-Lund, Atkins, Shelford, Ward, Whipple, Ringer, Juday, Ruttner, Thienemann).38
c. Nekton floats on the surface. It suggests its special problems, especially of what the author called “planonts”, beings living in the extreme surface layer and only to be studied by special methods.39 From ducks to mosquito larvae, and from mosquito larvae down to bacteria. Often, we meet with epidermitis, the causes of which are often imperfectly understood (See however v. Heusden),40…., Diatomea, Peridinium, Chlamydomonas or bluegreens, “waterblow”. This is especially important for waterworks and swimming pools.
d. At the bottom we findBenthos, chiefly animal in nature and living from the planktonic and nektonic debris roaming clones continually. Here we find animals with haemoglobin, detritus eaters as rotifers. Here we often find the curious community attracted by, or able to withstand hydrogen sulphide. Benthic organisms form some very good soil, maybe they also form the mother-like substance in the genesis of oil (epibiosis).
e. Further E[va]porites, that grow upon rocks, bridges or other organisms.41 Some of them make a current of water; others need living water (rheobionts as Hydromus). In small bodies of water nearly all of the organisms may belong to this group among which we mention bacteria, protozoa (Vorticella ….) diatoms, bluegreen and green algae etc.
f. Special communities. Special environments yield special communities. Hot springs, brackish waters and brines, acid waters or volcanic lakes all harbour special biocoenoses. The similarity between the several extreme communities is often striking. It seems that one meets the same actors at the exposed places. Naturally hydrobiology should take into account the bacteriological changes in its waters and in its sediments.
g. Sediments. However, the bacteriology of the mud shows the “gyttja” is still in its infancy.42
[Limnology] is the physical, chemical and geological counterpart of hydrobiology. It is, in the first place, concerned with the properties of water and how these properties show themselves in rivers, ponds, lakes and springs. In the latter part of the 19th century water analysis gave us knowledge of the:
a. Chemistry of natural waters. The data obtained admit of certain interesting generalisations. It appears that there are a limited number of types of natural freshwaters and that other types, chemically equally probable, or not seem to occur.
b. The physical properties of water, of course exert a great influence upon the living beings in the water. Some of these properties, like the absorption of radiation, have been studied chiefly under the influence of hydrobiology (Atkins). Others, of purely academic intent may become important later.
c. Physics and chemistry of large bodies of water. The maximum density of freshwater at about 4 °C causes intricate and entirely vertical currents to occur in deep masses of water. This is an example of the application of a physical principle. Chemical changes as well may be traced (Birge and Juday, 1926).43 They are, usually of biological origin.
d. Configuration of the bottom sediments. Lakes and pond deposits, chalybeate,44 lime or marl, or chiefly organic [substances], are an important part of limnology, not interesting only to the geologist, but to the agronomist and the bacteriologist as well. Here we often meet with periodic phenomena, and so called “varve” formation.45 We know;
e. Eutrophic waters, of an acidity and further chemical composition that enables copious development of different groups of inhabitants. Chemical factors are usually at the minimum for a very short time.
f. In oligotrophic waters, however, the nutrient salt contents as different and minimum phenomena may become chronic. Rheophilics often may hold out longest (mountain streams).46 These are:
g. Dystrophic environments, where high acidity, high alkalinity, high temperature or hydrogen sulphide or the lack of oxygen causes a diminution of the less hardy. Amongst these we mention:
h. Saline environment, a very specific milieu, widespread and hydrobiologically most interesting, as it challenges our cherished so called fundamental laws of physiology. The weird living circumstances of the strong brines is described in Section 3.13.5; 4.3.9 and 5.2.4, also:
i. Hot springs deserve special mention as here we find communities very similar to those in the brines. Out of a great many further limnological problems we arbitrarily select:
k. The origin of waters. Really, we should have started with this question, as there is no life and no hydrobiology without water. There is: vadose from the soil, juvenile from deep in the earth, meteoric from the atmosphere, metabolic from the decomposition of organic matter (see Section 3.5.18).
1.2.3 Marine biology and oceanography
There is of course a close relation with hydrobiology, of which both parts are, apparently not quite aware. All that has been said under hydrobiology pertains, apart from the fact that, although seawater covers 2/3 of the surface of our globe. The chemistry of seawater and physics of seawater are remarkably constant, so enduring we nowhere find a set of conditions on the whole earth. Our scope is, at the other hand, greater, for the expanse is vast. Pressure effects and light penetrations we may study from the depth of 10000 metres. Oceanographers have paid attention to influence of terrigenous material.47 This is, especially at the estuaries of rivers, of great importance. Frozen rivers, glaciers, may also carry enormous amounts of material. The whole problem of the charge river-sea enters here into play. More typical and even more important, is the configuration of the bottom, a study of which has in the last decades (Meteor, Wattenberg; Snellius, van Riel),48 yielded very important results. Part of the sedimentation problem enters here. The chief problem for the oceanography lies in the vertical and horizontal.
Current Bjerknes theorem,49 salinity and temperature being measurable entities fit to calculate the movement of the water. Oceanic currents are, at the other hand, a counterpart of the planetary rotation (precipitation, monsoons), which will be mentioned elsewhere. One of the chief shapers of brine depositions, has been studied extensively. It covers reef formation, foraminifera ooze,50 cocoa lithosphere.51 Also the silica, the iron, the phosphate and the manganese deposition enter into play.
The problem of tides and waves although of great interest, rather lies outside the scope of modern oceanography. In marine biology it is again the plankton, which are of paramount importance, especially for the fisheries. The role of the evaporites is much less great, although the fouling of ships and dolphins takes place under their influence.52 High sea or pelagic forms are contrasted with neritic, which stay in the neighbourhood of the land. Nekton is much richer than in freshwater, due to participating molluscs, worms and other animals. The same can be said of benthos, which especially in the neritic zone, is of marine biology. Life cycles of fishes (eel; Joh. Schmidt),53 as it is connected with the intricate habits of the organism as well as with the multiple complexity of the milieu (Gulf Stream, floating of freshwater on brine). The distribution of organisms in oceans is a special science. It is interesting to see that certain groups preponderate while others are virtually or almost absent (Amphibia, Molluscs). The origin of the ocean much speculation exists. It may not be a mere solution of primitive rock, probably deep going biological influences have played a role here. According to some we carry, in our blood serum, some “primitive ocean water”.54
1.2.4 Aerobiology and metereology
Leeuwenhoek ±1700 and later Pasteur ±1860,55 recognised that the air carries life in the form of spores of aeroplankton, as it was called by H. Molisch,56 Miquel, and later Lindbergh and Miss A. van Overeem who have made a careful study of this group of organisms. There are fully developed aphids, beetles and flies at 15,000 ft elevation, there are plenty bacteria moulds, especially at cloud bases. At our laboratory we raised a fern (Athyrium filix femina) from a spore caught at 4,500 ft elevation!57 Mosses are also very common. These organisms are carried by air currents, and the distance they may travel this way is subject to certain laws (Humphreys, 1920; Correns, 1939).58 Horizontal currents occur both cyclonal and semi-cyclonal. They distribute soil and volcanic ash over tremendous distances, often within a few months traveling across the entire globe. The organisms are brought at sometimes almost stratospheric elevation by vertical currents, cumulus formation, with willing whirlwinds or ascending air over a volcano. Modern meteorology helps us to trace the amount of air studied. The ecology of the air, also in view of the pollution problem, is hardly studied (Jacq).59
1.2.5 Summary and conclusions
What is common to the disciplines mentioned above? We have, apparently, gathered an impressive amount of data on the counter mould, or the “oikos” of life. Cataloguing and classifying we have discovered that the environment fits the organism (Henderson, 1913). We think this the best of all possible results for the terrestrial organisms that we know. This point of view pertains as long as we do not supplement our observation by experiments, as long as we do not study the possibilities of an organism in the laboratory. This of course, is not an easy thing to do, but taking into account most of the sources of blunders already made, we shall see that the pollution of the organism exceeds that of the natural milieu in many instances. We shall see further that there is resonance between specific environment and specific organisms. And it shall also appear that the organism exerts a profound influence on the morphology and on the metabolism of the earth’s crust.
1.3 Innenwelt and Umwelt
Von Uexküll has created in animal ecology, these terms [Innenwelt and Umwelt] which, in a sense cover our concepts of “milieu interne” and “milieu externe”.60 However, there are differences. While Von Uexküll includes in the “Umwelt” also the “psychical picture” the animal forms of its environment, we shall exclude this factor, in so far it has no material influence upon the environment. Study of “Innenwelt” and “Umwelt” is greatly hampered by the fact that in biology, even more as in physics, the problem of “non-interference” enters in. When we observe an organism, we are in most cases, already interfering. And we are interfering grossly when we experiment with it, when we tear it out of its milieu, culture it by itself on a sort of synthetic food, place it on a microscope slide (the milieu of which may be toxic), or on a jelly-like agar which it never dreamed of. Even if we observe from upon, we interfere. Therefore, for biology, as well as for medicine, the dictum applies “experimentia fallax” [deceptive experiment].
From a lot of circus animals, we cannot learn much about the “Umwelt” of the lion. We may learn something about the lion (inclusive the thorn on his tail),61 but the lion in its completeness we never meet in the circus. An animal or a plant as they actually live, we never meet in the laboratory. There will be a time when we know more about milieu, when we shall be able to perform this feat. The inner world of the organism holds a predestined element in the genome, in the chromosome garniture. It is predestined in as far as on the pattern of the genome the chances of the environment play. We know the most classical way in which Johannsen has derived the law of frequency and amount of variability as induced by the ambient world.62 If A, B, C and D etc. are factors beneficial to the growth of an organ, let’s say a leaf and a, b, c, d etc. factors harmful to such growth (sun or shade, rain or drought, cold or heat etc.), and these factors occurred in random combination we might expect, for 5 factors expectations which, when evaluated as +) for A, B, C, D and as -) for a, b, c, d to be the terms of the binomial (1+1)5. If the number of factors be infinite, we obtain, as a limit, the probability curve,
𝜎 being the “mean error” or “standard deviation”.
(See, however the extension given by Kapteyn, 1916).63
Now, is there outside the genome more to the “Innenwelt”? Is the ontogeny entirely predestined? Or is there another, innate, statistical variability independent of the milieu? This fact has never been tackled experimentally as far as the author is aware (Baas Becking, 1946b).64
Apart from the genetics, we have the factual milieu interne, which is a counterpart of environment, in as far as the organism has not created its own environment. In the warm blooded animal we meet with an organism in which the regulatory functions change in the outer environment! And not only may this milieu interne be kept constant. Man is, moreover, capable to create a fairly constant, artificial, outer environment. Umwelt und Innenwelt of man is one of the most interesting objects of study, but one of the most dangerous objects! For the student will be soon aware that man is trying to subdue the entire outer environment, and that a great imminent conflict lies at our door! However, most organisms do not cause this difficulty. Their regulatory functions are limited and they do not, for if they do, to a very limited extent regulate the outer environment. Barcroft may be very enthusiastic about a worm that digs a burrow and is able to live in it because of the wonderful properties of its haemoglobin, but this worm has not regulated its environment, it has become its counterpart, just as its tube is the mould of its body.65 It is unable to alter it except, may be, for digging another burrow into it. For the rest it is a slave of its environment.
General J. Smuts, a keen biological observer, has written a remarkable treatise in which he announces the concept of holism.66 Holism is no novel claim; it wants to understand “the organism as a whole”, as an entity, as a thing perfect in itself. After what was said in the preceding section it will be clear that an organism “out of its environment” is no longer “the organism”. This is not meant in a mystical way. No metaphysics is necessary to see the advantage of the holistic attitude. We shall see later, for example, that the entire living nature is connected, like a large texture, a large web. By this is meant not a blood relation, but a mutualistic exchange of substances, a sort of super-symbiosis (Section 7). This web of life is made up of nearly all of the known organisms. There are precious few that are able to live on, independently. But by the increasing recognition of this fact by the discovery of more nutrilites (organic substances necessary for the life of an organism and active in very small quantity),67 we come to the inevitable conclusion that in biology we have been just spelling words, not yet making sentences and much less; making sentences that make sense! Of course, this material exchange appeals to the chemist, but it is only an exposition of the mutual dependences of the organisms, which orders much more than chemistry alone! Umwelt, when free may be a vast area, covering the milieu of a number of organisms. When we take organisms as an oak tree, or a cow, we are dealing, biologically, with classes of organisms, grouped in their mutual dependence, around Bos Taurus L. or Quercus robur L., but the web continues, it covers more than we yet understand. O, the holistic concept is better than the bare organisational concept, as we are able to isolate the complex from its greatest connections, and to which it is joined by many links!
1.5 Definition of Milieu68
In the beginning of this section, the word milieu has been used to designate environment. It might be well to analyse this matter somewhat further. Milieu is the integration of the objective environmental factors. The milieu of a certain organism is not thought as an instantaneous picture but as the integration of the environmental conditions during a definite homogeneous vital stage of the organism. Milieu differs from Uexküll’s Umwelt in so far as the Umwelt contains, as already stated, unspecific elements. Redefinition of milieu, as given here, reminds one of Walther’s definition of facies in Geology.69 In Section 3 the concept will be further elaborated.
If the German school speaks of “Stoffwechsel”, exchange of substances, it means exchange between the external milieu, called “monde ambiant” by Bernard (1878) and the internal milieu, the “milieu interne”.70 This milieu interne is the integration of all the influences emanating from the organism itself and dictated by its genetic plan. If we therefore consider the earth in its exchange, and its “Stoffwechsel”, with the organisms, we shall find an expression of the “milieu externe”, chiefly in the organism, an expression of the “milieu interne”, chiefly in terrestrial changes. We might well say, therefore that, due to the biosphere, the earth has its own metabolism.
In brines just the biological factor has been sorely underestimated. We must apply caution not to overestimate these factors, however. At various places in this essay, we shall meet with instances where it appeared possible to select between a chemical and a biological agent, as the cause of a certain phenomenon. This treatise will deal chiefly with the relation of organisms with the external milieu. Only at a few places relations between internal and external environment shall be further analysed. It will be seen that the earth often does not provide the milieu optimal for a certain organism.
1.6 Statement of the Problem
There is a contrast between biology and the other sciences. Mathematics, since it soared away from Euclid, is, in a way, extraterrestrial. Physics has left the earth to become astrophysics; the chemistry of the distant universe becomes increasingly known. The geologist, even, considers the morphology and the lithology of the moon. Biology, however, is still earthbound. It seems at present, sterile to consider a non-Ptolomeo biology, a Copernican biology so to say, where we cannot observe other celestial bodies accurately enough to even indulge in speculation.71
There are two moments however, that strengthen our forces in the existence of a non-terrestrial biology. In the first place, where subatomic, atomic, as well as molecular states of matter seem to be inevitably connected with external circumstances, the living state of matter may be, under suitable environmental conditions, equally inevitable. This consideration, which is wholly intuitional, needs not interfere with the problem of the generatio spontanea, as it presupposes only a cosmic (or at least interplanetary) transport of spores or cysts, as already stipulated by Svante Arrhenius.72 The second thought, which encourages us to consider a non-Ptolomeo biology, is the fact that the extension of our science may be approached experimentally. Astrophysics, for example, is partly a laboratory science. If we knew more about planet’s chemical conditions on, let us say, the surface of Jupiter, where, according to Russell, ammonia and methane are paramount in the atmosphere and in hydrosphere, it should be possible to perform experiments in liquid ammonia at a suitable temperature.
Leaving further speculation aside, it seems useful, however, to remember that most probably terrestrial biology is only one mode of life; one “phenomenal” side of an environment science, which we only perceive in part. Radiation and gravity are the determining forces of the type; the mode of the terrestrial biology and, of the two, radiation is the most important. Gravity determines the distribution of the elements in and on the earth - the composition of the lithosphere, hydrosphere and atmosphere. Radiation determines, under more, its temperature. This temperature, average ±15 °C (278.2 °K) is situated within the range of liquid water. The biosphere coincides with the region in which water, is, at least in certain seasons, in the liquid state. Our biology is a water biology and living things contain so much water that much science that appeared as biology, only proved to be a description of the properties of this very universal compound. Where Goethe said, “Blut ist ein sehr besonder Saft”,73 it should be countered by what Ant. St. Exupéry exclaimes in his Terre des Hommes, “Eau, tu n’as ni goût, ni couleur, tu n’es pas seulement nécessaire à la vie, tu es la vie”.74
The biosphere covers the earth as an extremely thin green film. It is of water and of sunlight made, it is bathed in a solution of the lithosphere (the hydrosphere) and it is profoundly influenced by it. It inhales the atmosphere. But its relations are mutual; there is give and take. This thin green film influences the earth, its chemical composition as well as its physical properties. It influences the earth more than its disproportionally small content should lead us to expect. There exists therefore, a close relation between living things and the earth, a mutual relation. This relation we shall call geobiology. Quite recently in geological history, one organism has arisen, an organism with power to change the face of the earth. Man, who claims the earth as his own, by divine right (Genesis 1, 30), has initiated a geobiological epoch, which may be called the anthropic epoch. Man is, geobiologically, one of the most important agents and his influence deserves special treatment. The influence of other organisms has been chronically underestimated. Until recently, there has been a tendency to delegate geochemical phenomenon to chemistry. Even the genesis of petroleum has been viewed from this point of view. This should not amaze us when we see that the concept of geobiology required, and presupposed, the development of a vast body of sciences such as geomorphology, mineralogy, plant physiology, general bacteriology, etc. Sciences that, moreover seemed, at the onset, unrelated and hardly even mastered by a single person. In this anthropic phase of our science, moreover, economics and sociology sneak in as well. They touch the so called Humaniores, realms of human endeavour infested with emotionalism, dogma and preconception. At the onset therefore, our task seems rather hopeless. The strength of science, as G.N. Lewis has aptly said, lies in its naivité,75 and if we, ignoring all the future obstacles which shall later hamper our progress, simply start on a simple task of organising what we have been able from our own and from extraneous experience, we have done all that may be expected from us. For every specialist that reads this book, there will appear a vast lacuna. But it seemed, particularly in these days, when man seems driven to destroy most of the remaining biosphere, not without its use to make an attempt to formulate the skeleton of a geobiology, even if the result be incomplete, erroneous and biased. Maybe the book is not written for a specialist but for those who are curious to link their laboratory experiences to the manifold imagery of the field work. For those who consider, with Sergei Winogradsky,76 the pre-culture bacterium more or less as a lion in a zoo. Maybe there are such that, after a lifetime of laboratory work, feel a certain nostalgia for their old hounds in the field.
G.Th. Fechner in his [Vergleichende] Anatomie der Engelen (1854?) [= 1825] actually describes our planet if it were living, if it had its own metabolism.77 This metabolism of the earth is partly geological and partly biological. There are chemical reactions in the newly extruding magma, there are radioactive processes, but also there is the influence of the living surface film of the earth upon the composition of the atmosphere, upon calcite deposition, upon sulphate reduction, upon formation of crust-biolithic. Geobiology goes further than the metabolism than the “Stoffwechsel” of the earth crust. It also deals with the “Formwechsel”, the geomorphological influences of the living beings. Orogenesis is the process geophysical and geochemical, but reef formation is a biological process. The clay soil on which we live in Holland, a subfossil excrement, in a sense a coprolite of the heart-shell and the mussel. Chemical as well as morphological processes come into play and apart from these there is a physical influence of the organism, on thermal equilibria in the atmosphere. For instance, that creates another category.
1.6.1 Cyclic processes
In geochemistry it is convenient to think of most processes as cyclic. So, oxidation and reduction connect an element M, its highest oxide MxO4 and its hydroxide MH2. There will be energy required for the reduction, liberated as oxidation, there will be exchange of electrons, there will be travels of the element in the lithosphere and hydrosphere, the atmosphere and the biosphere. These happenings are recurrent. The show is continuous and all acts are enacted simultaneously!
1.6.2 Disturbances of the cycle
A cycle, in a way represents a departure from a stationary state only in that there is a “shift” in the equilibrium, which is recurrent. If the recommence in this shift is incomplete, our phase in the cycle will become exhausted, one product will accumulate, like a factory artefact, manufactured on one endless belt. This may be due to a difference in velocity between the various links in the chain process. The acid medium, for instance, certain bacterial processes may be slowed down, here we may get accumulation of organic material that would not occur in alkaline medium. In this way, through a disturbed cycle, we may explain most biogenic accumulations in nature. Our oil, coal, and great deposits, saltpetre, guano and, to a certain extent, brine are all to be considered as “slugs” in the cycle of the carbon. Role of organisms (coal, oil, brine deposits).78
1.6.3 Contents of this book
This book deals with the organism and the earth. It will endeavour in a short scope, to describe the earth as an abode for life, the physical, the chemical and the biological factors of the milieu. Then it will deal with living matter in its longer aspect as far as distribution and metabolism is concerned. The third part deals with the influence of the environment upon the organism, and the relation of the organisms to a laboratory environment. The fourth part treats the influence of the organisms upon the atmosphere, the hydrosphere and upon the lithosphere. After that the mutual relation of organisms shall be described. Man, as maker of milieu, deserves a separate section. A few theses appear in this book, which ask for a separate amplification before starting. They are simple and obvious, yet they seem forgotten.
a. “Nothing in the world is single”,79 is more than a line written by a poet in love, it does not pertain to that form of symbiosis which we may call “gamosymbiosis” alone.80 Even the independent, autotrophic higher plants are, in their flower biology, connected with insects, in their host biology with fungi. Not only the classical cases of symbiosis, but nearly all synecological questions stipulate the dictum used by P.B. Shelley. In the accompanying figure some relations between six organisms are depicted. The relations vary from true symbiosis to parasitism and the food relation. Even within a multicellular organism, the individual cells and tissues live in mutual relation. Life, therefore, is a complicated web, spread over the earth. A magic web, of which not a single strand may exist without its own, elaborated strands (Fig. 1.1).
Geobiologically this thesis, which will be elaborated in Section 7, is of the utmost importance. It is, in the first place, hard to indicate a certain organism as the agent of a specific geochemical reaction. We have to know the whole complex of organisms centring around that particular point in the web of life. Furthermore, most of the relations indicated above are material relations. There is continuous exchange or rather interchange of chemical substances between organisms. This interchange is, of course, part of the “terrestrial metabolism”, and the shape of the milieu has to be the common denominator of the environments of all of the organisms, which cover this part of the web.
b. “Everything is everywhere”.
The founder of general microbiology, M.W. Beijerinck, has intuitively employed both principles, which are expressed above. In his masterly lecture for the Royal Academy of Sciences in 1913 he has outlined a method of approach of microbiology, which is founded on the fact that if one prepares a specific nutrient medium and maintains this medium under specific conditions, any infection material will yield an identical organism.82 So, Van Niel isolated in 1929 purple sulphur bacteria from almost any infection material by keeping pH, H2S pressure and mineral composition specific, while illuminating his cultures.83 Specific instances of the method are given in Section 3.1 of this treatise. The section on distribution will give the experimental indication that most microbes are cosmopolitan, and that, therefore the “milieu-laws” apply.
In the schematic representation, given below (Fig. 1.2), the organism, whose milieu is described by field A lives in freshwater, aerobically, in the dark. This is not a very specific milieu. Organism B however, lives anaerobically in the light in a salt solution. It is most probably a bluegreen alga or a Euglenoid, as these are the only photosynthesis capable of living anaerobically in brines. By preparing such milieu conditions one of the two last named would be the answer! The organism resonates with the milieu. The above theses have met some opposition. The criticisms of Dr. J. Heimans shall be dealt with in this essay.84