SCIENCE 



FRIDAY, AUGUST 12, H 



WHAT AMERICAN ZOOLOGISTS HAVE DONE FOR 

 EVOLUTION.' 



Ladies and Gentlemen, — Eleven years ago I had the honor 

 of reading before this association an address in which an attempt 

 was made to show what American zoologists had done for evolu- 

 tion. My reasons for selecting this subject were, first, that no 

 general review of this nature had been made ; and, second, that 

 many of the oft-repeated examples in support of the derivative 

 theory were from European sources, and did not carry the weight 

 of equally important facts the records of which were concealed in 

 our own scientific journals. Darwin was pleased to write to 

 me that most of the facts I had mentioned were familiar to him, 

 but, to use his own words, he was amazed at their number and im- 

 portance when brought together in this manner. The encourage- 

 ment of his recognition has led me to select a continuation of this 

 theme as a subject for the customary presidential address, — a task 

 which is at best a thankless if not a profitless one. Had I faintly 

 realized, however, the increasing number and importance of the 

 contributions made by our students on this subject, I should cer- 

 tainly have chosen a different theme. 



Incomplete as is this record of ten years' work, I am compelled 

 to present it. In the Buffalo address two marked periods in the 

 work of the zoologists in this country are recognized : the one period 

 embracing the work of the topographers, the field-surveyors in the 

 science ; the other period dating from the advent of Agassiz, with 

 the wonderful impulse he imparted to the study by his enthusiasm 

 and devotion. A third period in American zoological science, and 

 by far the most important awakening, dates from the publication 

 of Darwin's ' Origin of Species.' Its effect on zoological literature 

 was striking. The papers were first tinged with the new doctrine, 

 then saturated, and now, without reference to the theory, derivation 

 is taken for granted. 



As zoologists, we are indebted to Darwin for the wide-spread 

 public interest in our work. Before Darwin, the importance of our 

 special studies was far outweighed by the practical value placed 

 upon science, in the application of which an immediate material 

 gain was assured. Chemistr)', physics, geology, were important 

 only because a practical application of these sciences was capable 

 of showing an immediate material return. 



Agassiz, in his appeal to the State for appropriations for the great 

 museum at Cambridge, insisted that there were higher dividends 

 than money ones to be looked for in endowments for zoological 

 museums, and these were intellectual dividends. While the force 

 of this appeal will always remain true, the transcendent importance 

 of the naturalist's studies from the standpoint of Darwin is widely 

 recognized. Man now becomes an object of rigid scientific scrutiny, 

 from the new position which has shed such a flood of light upon 

 the animals below him. 'His habits, behavior, the physical in- 

 fluences of his environment and their effects upon him, transmission 

 of peculiarities, through the laws of heredity, — all these factors are 

 directly implicated in the burning questions and problems which 

 agitate him to-day. Questions of labor, temperance, prison-reform, 

 distribution of charities, religious agitations, are questions immedi- 

 ately concerning the mammal man, and are now to be seriously 

 studied from the solid standpoint of observation and experiment, 

 and not from the emotional and often incongruous attitude of the 

 Church. To a naturalist it may seem well-nigh profitless to discuss 

 the question of evolution, since the battle has been won ; and, if 

 there be any discussion, it is as to the relative merits and force of 



1 Abridged from the address to the American Association for the Advancement of 

 Science, at New York, Aug. lo, 1S87, by Prof. E. W. Morse of Salem, Mass., the 

 retiring president of the association. 



the various factors involved. The public, however, are greatly in- 

 terested in the matter, as may be seen by a renewal of the fight in 

 the English reviews; and the agitation is still kept up by well- 

 meaning though ignorant advisers, who insist that science has not 

 yet accepted the doctrine ; and great church organizations meet to 

 condemn and expel their teachers of science from certain schools of 

 learning because their teachings are imbued with the heresy. 



Dr. Asa Gray, in his discriminating biographical memoir of Dar- 

 win, says in regard to the ' doctrine of descent,' " It is an advance 

 from which it is evidently impossible to recede ; as has been said of 

 the theory of the conservation of energy, so in this the proof of 

 this great generalization, like that of all other great generalizations, 

 lies mainly in the fact that the evidence in its favor is continually 

 augmenting, while that against it is continually diminishing as the 

 progress of science reveals to us more and more the workings of 

 the universe." Let us examine, then, the evidences, trivial as well 

 as important, that have been recorded by American zoologists with- 

 in the past ten years in support of the derivative theory. 



Without further apology for the very imperfect character of this 

 survey, let me at once begin by calling attention first to the testi- 

 mony regarding the variation in habits, and evidences of reasoning- 

 power, in animals. The establishmerit of individual variation in 

 mental powers, change in habits, etc., lies at the foundation of Dar- 

 winism as furnishing material for selective action. There is no 

 group of animals which exceeds the birds in varied and suggestive 

 material for the evolutionist. It is a significant fact that the birds, 

 which appeared to Cuvier and his contemporaries a closed type, — 

 a group that seemed to fulfil the ideal conception of a class arche- 

 type as compared to other groups which had their open as well as 

 obscure relationships, — should be, of all groups, the one that first 

 yielded its exclusive characteristics. In fact, there is no group in 

 which the barriers have been so completely demolished as in this 

 apparently distinct and isolated class. An attentive and patient 

 study of the birds has established almost every point defined by 

 Darwin in his theory of natural selection. One has only to recall 

 the marked reptilian affinities as shown in their embryological and 

 paleontological history. Besides all these structural relationships, 

 the birds possess, as a group, remarkable and striking illustrations 

 of variation in color, size, marking, nesting, albinism, melanism, 

 moulting, migration, song, geographical variation, sexual selection, 

 secondary sexual characters, protective coloring ; and in their habits 

 show surprising mechanical cunning and ingenuity, curious and in- 

 explicable freaks, parental affection, hybridity : indeed, the student 

 need go no further than the birds to establish every principle of the 

 derivative theory. 



The many observations on the nesting habits of birds would 

 form a curious chapter as illustrating the individual peculiarities of 

 these creatures. 



Mr. J. A. Allen, in writing on the inadequate theory of bird's- 

 nests, shows grave and important exceptions to Wallace's theory, 

 though he subscribes heartily to his philosophy of bird's-nests. 

 He expresses surprise that closely allied species of birds should 

 oftentimes build divers kinds of nests, overlooking the fact that 

 even closely allied varieties of man build entirely unlike houses. 



The behavior of wild birds when kept in confinement, and the 

 attempts made in domesticating them, has always furnished an in- 

 teresting field for study. The curious freaks and impulses which 

 they often betray, the changes they show under the new conditions, 

 indicate in some measure the plasticity of their organization. 



Hon. John D. Caton, in an interesting paper on unnatural attach- 

 ments among animals, records a curious fondness shown by a crane 

 for a number of pigs ; and in another paper on the wild turkey 

 and its domestication, this writer has made some valuable records 



