Natural Co-ordination as evinced in Organic Evolution. A Paper read by William Fraser, M. D., before the British Association for the Advancement of Science at its Montreal Meeting, September 1, 1884. New Glasgow, Nova Scotia: George W. Chisholm.
It it would be too much to say that Dr. Fraser, in this philosophical essay, has solved the supreme question of the nature of that governing power by which an evolving universe works out its highest results, it is not too much to say that he has made a reasonable and a valuable contribution toward such a solution. We can not here give his closely knit argument, but must be content with indicating the ground taken. He begins by remarking that "matter and force constitute the present scientific basis of the natural universe; but as unco-ordinated entities they might remain forever inoperative." This idea is so illustrated and enforced as to bring out the necessity of affirming a presiding directive and co-ordinating principle as a part of the order and constitution of Nature, and without which development is a wholly inexplicable process. Dr. Eraser's statement of the case of evolution as against special creation, and in the variety of its proofs, is thus admirably summarized:
From studying the question under other aspects, some observers have been induced to adopt an opposite view, and to conclude that all actual diversities were potentially Inherent in matter and energy at their original creation and disposition, and have been spontaneously evolved through natural causes, without any supernatural interference.
Having learned the apparent potency of natural means and methods in producing all past physical changes, they feel constrained to recognize these as fully adequate to sustain tho whole sum of terrestrial activity, including the processes and products of organization; deeming it more credible that the total system of development, in common with all other material objects and events, should form an essential and interdependent part of the more comprehensive scheme of Nature, than that each distinct species should have its source in a miraculous act of creation.
Observing, under varying artificial conditions, tho occasional production of several acknowledged varieties from a common stock, and the perpetuation of such only as can provisionally conform with the conventional requirements of their situations, they infer that species originated and have been transmitted in a similar way, but carried further and established more firmly, either in consequence of more powerful impulses or of greater time and opportunities afforded.
They also find that all the species of the same genus, inhabiting adjacent and intercommunicable areas, have closer structural relationships than those of more remote and mutually isolated regions, and that any differences which exist in the former case are superficial, as if the later divergences had rarely and but slightly affected their fundamental characters.
Fossils also are generally found more nearly allied to the fauna and flora of their own particular territory than to those of distant provinces; and in the later deposits more so than in those of earlier strata.
Paleontological arrangements likewise Indicate a gradual advance from generalized to specialized forms, from the simple earliest structures up to the relatively complex types of the present age.
Embryological development also shows a general progress from the indefinite to the definite; all organic germs at their origin being scarcely distinguishable from one another; the earlier foetal stages of many different classes of animals being almost parallel; and in the higher orders, their later phases being attended by a gradually decreasing number of companions, till man, the highest vertebrate, at length alone acquires distinctively human features. Besides, underneath certain diversities of surface, which constitute specific morphological distinctions, there is often a fundamental unity; the arms of a man. the flippers of a whale, the fore-legs of a horse, and the wings of a bird being constructed on essentially tho same general pattern, though differing greatly in special details, as if a common ancestral organ had become differently modified in each particular case, in subordination to, and in conformity with, correlated conditions.
Rudimentary structures often show the potency of heredity in preserving parts long after they have ceased to be serviceable; and occasionally they represent the transition to some more complete and permanent advantageous acquirement.
In general, the more invariable and radical organic structures are diffused among much larger aggregates than are less permanent and less important ones.
The spinal column, which pertains to the whole vertebrate sub-kingdom, holds tolerably constant specific characteristics within the same class, whereas the dermal appendages not only manifest much diversity in different species, but often display considerable difference even in members of the same variety.
All these complex and diversified relations are considered indicative of community of origin, with subsequent adaptive modifications.
Certainly geographical distribution, geological
