The theory of evolution in the light of facts, by Karl Frank, S.J. with a chapter on ant guests and termite guests by P.E. Wasmann. Translated from the German by Charles T. Druery...with 48 illustrations.

EVOLUTIONacquainted with this dreaded animal.A single picture is there indicated with the name of 'The Wolf ' beneath it, and yet it is expected that the child will recognize by this single picture all wolves which it might ever see in any zoological garden.Similar animals, but not wolves, are the Dogs, wild and tame, and the Foxes.The make of the paws, the toes, the entire habit and mode of life (Carnivora) are very similar ; on the other hand they differ entirely in all these characters from the Sheep, Goats, etc.On the strength, therefore, of the said similarities the wolf, dog, fox, etc., are placed in a higher systematic unit, viz. in the dog family of the Canidse.Particularly in the shape of the jaw (carnivorous jaw) all dog-like animals resemble the Bears, the Marten, and others ; all these animals can therefore be united to a further group, viz.that of the land Carnivora {Carnivora fissipedia).According to the similarities which even then remain between many groups, the allocation of animals to higher units progresses, which naturally then become ever more and more general and comprehensive.The land Carnivora are united with the aquatic Carnivora (Pinnipedia) to form the order of Carnivora ; then with all sucking animals to form the class of Mammalia ; and finally with all animals which possess a skeleton formed of jointed vertebrae, to form the tribe of Vertebrates.It is now a question whether this graduated division, which renders it possible for us to unite all animals and plants into a few tribes and classes, is only the expression of a general plan which, the Creator wished once and for all to realize, or whether this similarity rests really upon actual relationship (blood-relationship).We can easily come to the latter conclusion, since in point of fact we observe that the greater the resem- blance between definite individuals so much the closer is the true blood-relationship.Children, as is often said, resemble the parent like ' their very image,' and brothers and sisters are, as between themselves, of the greatest similarity.Negroes, Indians, Chinese are also ' true ' men and resemble the Europeans, but the reason of their perfect racial resemblance, which is shown by the Negro, we seek and find again in their descent from black parents, in their close or more distant blood- relationship.Ought we or must we therefore also, in order to explain that Europeans, Negroes, Indians, etc., are all men, accept a common descent for all and therefore an actual blood-relationship, even though it be a cousinship 1000 or 10,000 degrees removed ?The same question can also be raised in view of the similarity of the systematic hierarchy established for animals and plants.Is every resemblance, be it ever so trifling-as, for instance, the possession of a vertebral column -^the expression of an actual blood-relationship,or-what is the same thing-the descent from common progenitors in the dim and distant past ?The question cannot obviously be determined a 'priori nor even by the direct observation of the animal and plant forms of the present day.We observe, indeed, that blood-relationship (descent from the same B 2 ' species.'Compare Wasmann : Die Moderne Biologie und die Entmcklungs- theorie, chap.x.' The man of evil luck's remains likewise from out the ground Have now been dug, and for it many reasons have been found.'(p.66, Translation.)This ' man of evil luck ' (' a disturbed skeleton of an old sinner ') even- tually proved to be the skeleton of a gigantic Salamander (now in Haarlem).' catastropliic ' and ' creation ' theories do not afford the most natural explanation of the history of life upon the earth.Another hypothesis was, however, still impossible so long as the absolute unchangeability of the organisms was adhered to.Already, in Cuvier's lifetime for the first time, serious attacks began to be made on the ' constancy ' theory in order to permit the possibility of another signification being given to palseontological facts, and particu- larly to establish an actual connection between the present and fossil organisms.Lamarck and GeoffroySt. Hilaire had already, decades before the appearance of d'Orbigny's ' Cours elementaire,' put forward theories on quite new and unheard-of lines.But their ideas found no proper response among their contemporaries.It was reserved for Charles Darwin to obtain for the new doctrine a general acceptance ; in what sense that should be properly understood we shall speedily see.All agreed that the living and fossil animal and plant forms are connected genetically, i.e. by descent.Thus the many new creations became superfluous.These were, indeed, only insisted upon because that connection was denied.The difference established by palaeontology of offspring between themselves and from their ancestors finds its explanation in the variability of the organisms, which, in the sharpest contradiction to the ' constancy theory,' became re- garded as a fundamental quality of all living things.Since palaeontology furthermore presented some evidence that the difference of form of the progeny was ' catastrophic ' theory would also be superfluous, and despite it a so thorough transformation of the organisms should not be accepted as established, since experience now appears to contradict it.Next there should be remembered the words of d'Orbigny regarding the ' complete ' divergence of the earlier forms from those of to-day, which were not shaken even by some examples of striking constancy within very narrow limits of relationship, which have continued from the oldest periods to the present.How the unchangeability of living organisms is to be regarded we shall consider later on.For the rest it is inexphc- able how precisely those differently formed animals and plants in the strata accessible to us have been ' From the older strata of the Jura and from the Trias (which come next into consideration) we know practically nothing of small, long-legged reptiles of such a habit as the Archseopteryx demands as ancestor.'Deperet- Wegner : Die Umbildung der Tierwelt, p. 231 : ' The Archseopteryx is, however, a true bird in its entire construction, and possesses beyond doubt a long line of ancestors which at present eludes our knowledge.'

Topic: Evolution and Science Education
Subfield: History and Philosophy of Science
Field: Arts and Humanities
Domain: Social Sciences