If the genome of any species is an expression of the ecosystem it needs, then there must be specific ways in which aspects of the ecosystem that that species has experienced during its evolution gets expressed within genetic structure, which consists both of the substance of the chemicals and their form (their specific shapes). This marriage of substance and form in structure expresses internally the aspects of the external world needed by the organism. For instance, hemoglobin is, in part, the internal expression of oxygen-in fact oxygen must physically fit into the structure of the hemoglobin protein molecule. The fit is so good that, at typical lung air pressure, hemoglobin is 98 percent saturated with oxygen. For a large variety of animals, the part of the genetic structure that produces hemoglobin can therefore be viewed as one expression of the oxygen component of the ecosystem. That same genetic structure also expresses carbon dioxide, which hemoglobin transports out of the body via the lungs, as well as nitric oxide, which regulates blood pressure.

We might also consider the correspondence between the genetic structure of chloroplasts and mitochondria, which are internal to cells, and the carbon dioxide and oxygen in the atmosphere.

Chloroplasts, which have their own DNA, are the reducing agents in plant cells that convert sunshine, carbon dioxide, and water to carbohydrates and oxygen. Mitochondria, with a DNA structure similar to chloroplasts,14 perform the reverse function by oxidizing carbohydrates to yield energy, water, and carbon dioxide. Were there no genetic structure within chloroplasts and mitochondria that allowed for recognition of carbon dioxide and oxygen, the overall oxygen and carbon cycles in Nature that are needed to sustain life simply could not exist.

At another level, we might consider internal cellular differentiation, which occurs mainly through the differential expression of genes that are present in every cell. The sequence, rate, and entire environmental context, from the intra-cellular to the ecosystem level, in which genes are turned on and off determine the specific outcome of the cellular developmental process. In view of this, geneticist D. J. Pritchard has noted that gene expression can be viewed as an incorporation of the environment into the living being:

"Gene expression is controlled directly or indirectly by the intra- and extra-cellular environments to which the DNA in which the genes are encoded is exposed, while components of the environment become incorporated into bodily structure as a feature of expression of the genes. Phenotype at all levels is thus the product of interaction between the genome and the environment and either can be limiting."

That there is no simple one-to-one relationship between function, ecosystem feature and genetic structure is obvious from the simple example of a single protein, hemoglobin, that fulfills many functions that interact with the functions of other genes (in maintaining and changing blood pressure for instance). As another example, the color of the jaguar's coat not only plays a role in camouflage, but also in the rates at which its body absorbs and radiates heat. Other aspects of its coat, texture and thickness, also play a role in its heat balance.

There are also many potential ways in which genes express a specific aspect of the environment, so that there is no necessary "best" answer to the problem of survival for living beings in a specific ecosystem. There is also considerable evidence of redundancy of function in genetic structure, indicating that the ecosystem of the organism is expressed in many ways within that organism even for single functions. Finally, if there are multiple potential genetic expressions of ecological realities, a profusion of species and subspecies becomes more understandable.

Evidently, the internal expression of the ecosystem in us is not a point-to-point map. Far from it. The same physical conditions have produced a large variety of organisms corresponding to them, as biologists Richard Levins and Richard Lewontin have observed. One can understand this from an informational standpoint. For instance, much of the prey's specific internal structure is irrelevant to the predator. This allows a variety of insects to be expressed in the same internal biology of the predator, since, for the predator, the essence of the prey is its catchability and its digestibility. The crocodile needs to sense that the insect is edible and flies. This raises the possibility that there may be many different genotypes that could make use of essentially the same external phenomena to grasp the insect as food. And, indeed, there are-birds and crocodiles, for example.

Further, in complex living beings, organs are the internal expression of a living being's ecosystem beyond the level of single cells or gene-protein relationships. Both excorporation and incorporation occur via the organs, which are the internal biological instruments of the genome-ecosystem where the instinctual grasping actually takes place. More than that, organs are also among the principal locations of non-genetic adaptation to the environment that necessarily occurs in the process of living.

Non-genetic adaptation, which is one aspect of what one might call need-learning, results in non-genetic need-knowledge, and is as fundamental to survival as genetic adaptation. The incomplete representation of the essence of the external by integration of a set of phenomena not only produces vulnerabilities, for instance, to parasites, but also enables a variety of external phenomena within broad parameters to be represented in the same way. Many different insects can be represented internally in the same way as food, without much special regard to the differences between various species. This property allows specific species to adapt to new environments (within limits) without genetic change. The individual crocodile in a new location will learn to recognize the different species of insects that are present. This plasticity of response does not arise from genetic change, but from the fact that the relationship of an individual's genetic structure to the external is mediated by internal systems (organs) that are themselves adaptive.

Order, Information, and Need

Physicist Erwin Schrödinger, in his essay What is Life?, noted that the process of living was the reproduction of "order based on order"-ordered genetic structures reproducing themselves by the process of living. The creation of order is a reduction of entropy and is understood as such in the second law of thermodynamics in both its thermodynamic and informational interpretations. The maintenance of low entropy-that is a high degree of order-using energy mainly from the sun is a central physical characteristic of the reproduction of ecosystems by living beings. Some of the defining aspects of the low-entropy state that characterize living beings are in genome-ecosystem relationships, which depend on internal structures, like brains and bladders, needed to establish them, as well as physical phenomena like sound waves and chemicals like pheromones, that mediate them. The crocodile needs far less information about the insect than the mate of the insect-and mates can gather more information about each other because their genetic structures are very close. In this way, the expressions of genetic structure serve, in part, as differential filters for information according to need. Is the need, for instance, for a mate or a meal? Of course, there are also non-genetic aspects of information filtering.

Complex beings also adapt by changing behavior. The brain seems to have evolved in them as an organ that expresses both the external ecosystem structure as well as internal biology. It mediates and regulates relations between the two. In this view, the brain is a specific internal biological expression of external survival needs, which necessarily have social, including behavioral, aspects. While change in behavior involves internal changes, in what is remembered, for instance, it may or may not involve development of organs. In other words, behavior provides an additional level of plasticity-that is, the capability for behavioral adaptation to new phenomena without concomitant genetic change. Developmental and behavioral factors mean that genetic structure is, within limits, shielded from many kinds of environmental change. However, at any time different species are shielded in different ways and to different extents, with the result that adaptation by species at all levels is occurring simultaneously within an evolving ecosystem as a matter of course.

We may deduce from the above that the genome of a species does not represent a "snapshot" of the external environment as it exists at any time. First of all, genetic change is not instantaneous. Secondly, as we have noted above, it does not need to be, since there is substantial non-genetic adaptability in organisms. Our muscles and livers and brains can and do change in response to developmental and environmental factors without corresponding genetic change. As a corollary we may postulate that the collection of species that exists at any time is not genetically contemporaneous with the external environment. This has some implications for the reproduction of ecosystems and for evolution.

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Endnotes

¹Campbell 1996, p. 846.

^{2 Both have a closed circle DNA structure. For illustrations, Kimball 2000.
^{3 Childs 1996. For a philosophical discussion of mitochondria and humans, see Thomas 1974.
^{4 Pritchard 1990, p. 151.
^{5 See Strohman 1997 for a discussion of the role of many genes in single functions. The one-gene, one-protein model is, in any case, being discarded, partly due to indications that there may be far fewer genes in the human genome than previously thought and that this number is only about a factor of two greater than the number of genes in a roundworm's genome. See Gould 2001.
^{6 Levins and Lewontin note that "[t]he consequence of the interaction of gene, environment, and developmental noise is a many-to-many relationship between gene and organism. The same genotype gives rise to many different organisms, and the same organism can correspond to many different genotypes." Levins and Lewontin 1985, p. 94. See also Lewontin 2000, pp. 53-68.
^{7 As a speculative corollary of this line of thought, one might ask whether the folded structures that characterize genetic and protein structure may be the result of convolution processes by which the external environment becomes expressed in internal living structures.
^{8 Edward Goldsmith has called living beings "intelligent" in this sense of adaptation. See Goldsmith 1998, Chapter 32. However, as in the case of biological knowledge, biological adaptive learning should be distinguished from the processes by which human society creates printing presses and books. There is ample evidence that adaptive learning and the consequent adaptive, non-genetic, need-knowledge exists in non-human species. Consider, for instance, the capuchine monkeys of Venezuela who, during peak mosquito season, know how to find and apply mosquito repellent. They collect a species of millipede rich in benzoquinones, which are powerful mosquito repellents. They crush the chemicals out of the millipedes and apply them to their bodies. The monkeys don't have knowledge of benzoquinones in the Cartesian intellectual sense that the researcher who studied them does, but they nonetheless grasp the essentials instinctually, and with fine enough timing to be able to ward off mosquitoes effectively at the peak of the mosquito season. Angier 2000, p. D5.
^{9 Schrödinger, 1967 edition, p. 68 and Chapter 5, more generally.
^{10 For a discussion of orderliness, disorderliness, and entropy that includes the environment of the organism, see Turner 2000, pp. 11-25 and pp. 116-119.

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