As an alternative to the precept that natural selection produces adaptation, there will be presented here a summary of “The Four Principles of Adaptation” (Hulburt, 2002). The merit of the approach in this study is that adaptation is considered to be the present adjustedness of biota to their environment and to each other – and, as well, the present lack of adjustedness of biota to their environment and to each other. For it would be naïve in the extreme to expect only adaptedness, adjustedness, everywhere always. Moreover, the precept of natural selection is ambiguous with respect to adaptation. Thus from Stern (1970) we have 1): “whatever has been produced by selection is to be designated as better adapted” has the contrapositive; 2): whatever is not to be designated as better adapted has not been produced by selection. 1) and 2) together form a logical whole. But equally well 1) can be elaborated into a logical whole without negation as 3): whatever has been produced by selection is to be designated as better adapted and whatever is to be designated as better adapted has been produced by selection, so that the selected is equivalent to the better adapted. In 2) a badly adapted component of nature is suggested to occur and in 3) no badly adapted component of nature is allowed. In what follows both 2) and 3) will be of concern, in the sense that nature does have both well adapted and badly adapted components in some cases and only well adapted components in other cases.

But to see the options of these cases a wholly different approach will be taken. The approach will be that a factual, observational basis must exist and adaptation must be inferred from it. To this end the four principles of adaptation of Hulburt (2002) will be presented and these will be seen to emerge from the factual situations that accompany the principles.

The First Principle
The first principle is that if two quite different entities occur under the same condition, then one is adapted and the other is not adapted to this condition. Thus the warm-blooded vertebrate is adapted to year-round temperature in temperate regions because it is behaviorally active year-round (except hibernators), whereas the cold-blooded vertebrate is not adapted to year-round temperature because it is not active year-round (plus hibernators).

Put in logically valid form, this is as follows: if x is in a year-round active animal (a squirrel), then x is in an adapted animal, one that has adaptedness to year-round temperature – equivalent to: if x is in a not-adapted animal (a toad), one which does not have adaptedness to year-round temperature, then x is in a not year-round active animal. The x is single from one adapted animal to the other unadapted animal, each kind integrated by the single property of adaptedness or by the single property of unadaptedness. The single x integrates the two opposing kinds (the squirrel kind and the toad kind).

The Second Principle
The second principle is that if one entity occurs under two quite different conditions, then it is adapted to one condition but is not adapted to the other condition. Thus the North American forest is adapted to moist conditions in the east and west but is not adapted to the non-moist conditions of the semi-arid southwest U.S.A. Put in logically valid form this is as follows: no matter what y is chosen, if the forest is adapted to y then y is a moist condition – equivalent to: for any y if y is not a moist condition then the forest is not adapted to y. Briefly: the forest is adapted only to moist conditions if and only it is not adapted to non-moist conditions. In part the forest is composed of tall densely packed trees, whether in the diverse, deciduous forest of Appalachia, or in the spruce forest of northeastern Canada, or the varied evergreen forest of the Rocky Mountains and Pacific northwest – all moist regions – and in part the forest is composed of depauperate, spaced-apart pinon pine and creosote trees of the semi-arid southwest U.S.A. It is the view here that the depauperate forest of the southwest is a mute spokesman of the contrast between the unadaptedness that it exhibits with the adaptedness that the tall densely packed forest exhibits. It is the same forest in both places, its contrasting characteristics being spatially and thus non-contradictorially separated – just as the same tree species is tall and well-formed away from the coast but short and gnarled on the windswept coast.

The Third Principle
The third principle is that if one entity is adapted to a second, then the second is adapted to the first. Thus the white spruce was adapted to an expanding locale between 12000 and 9000 years ago in the mid-west of North America, and this locale was adapted to the spruce. For the sake of logical validity and for driving the point home, we have: if the white spruce was adapted to its expanding locale, then this locale was adapted to the white spruce, and if this locale was adapted to the white spruce, then the white spruce was adapted to it – equivalent to: spruce was adapted to locale if and only if locale was adapted to spruce. But of course, the smallest plant is adapted to the spot where it stands and this spot, this habitat, is adapted to it. The habitat must be adapted to the plant, otherwise the plant would not be there. Likewise, the locale must be adapted to the species, otherwise the species would not be there. This is the most crucial feature of ecology.

The Fourth Principle
The fourth principle is that if two quite different entities occur under two quite different conditions, then one is adapted to its condition and the other is adapted to its condition. For example, and in logically valid structure: there is diapause or there is non-diapause in insects; if there is diapause (an insect in an overwintering larvae stage) then there is winter adaptedness, and if there is non-diapause (the same insect is in a winged stage) then there is summer adaptedness; so there is winter adaptedness or summer adaptedness. We have two mutually exclusive and jointly exhaustive stages – as we do in leafless and leafy trees, in below ground and above ground parts of perennial plants, in seeds and plants of annual plants. And paleontologically and evolutionarily we have a tendency (an entity) toward many boned toes of paddle limbs of aquatic vertebrates and this is an adaptation to swimming, and there is a tendency toward two or three toes instead of five in land vertebrates and this is an adaptation to running (Fig. 1). And all of these pairs can be put in the logically valid structure of the insect example, for this structure is as much a part of reality as the biota that make up its content.

So this presentation distinguishes between cases where adaptedness and non-adaptedness pertain in the first and second principles, and cases where only adaptedness pertains, in the third and fourth principles.

The first principle is elaborated in Hulburt (1992), the third principle is part of the structure of Hulburt (1996, 2000) and the fourth principle is exemplified by cases in Hulburt (1998).

References
Carroll, R. L., 1988. Vertebrate Paleontology and Evolution. W. H. Freeman and Company, New York, p. 698.

Hulburt, E. M., 1992. Equivalence and the adaptationist program. Ecol. Model. 64, 305-329.

Hulburt, E. M., 1996. The symmetry of adaptation in predominantly asymmetrical contexts. Ecol. Model. 85, 173-185.

Hulburt, E. M., 1998. Theory of adaptation: application of symbolic logic. Ecol. Model. 107, 35-50.

Hulburt, E. M., 2001. Non-interference and reciprocal adaptation. Ecol. Model. 2001, 1-13.

Hulburt E. M., 2002. The four principles of adaptation. Ecol. Model. 156, 61-84.

Stern, J. T., 1970. The meaning of ‘adaptation’ and its relation to the phenomenon of natural selection. Evol. Bio. 4, 39-66.

Figure 1. Uppermost figure: The plesiosaur Hydrothecrosaurus, Jurassic, 12 m. long. Next to the top figure: the icthyosaur Shonisaurus, Upper Triassic, 15 m. long. Middle figure: the mosasaur Plotosaurus, Upper Cretaceous, 10 m. long. Bottom figure: left pair, the artiodactyls Proebrotherium and Protoceras, Oligocene; right pair, the perissodactyls Hyracotherium (left) and Tetraclaenodon (right), Lower Eocene (from Carroll, 1988, pp. 248, 256, 234, 515, and 529).