682 A CENTURY OF PROGRESS IN THE NATURAL SCIENCES 



reports, emphasis was placed on the distribution of species, but much new material 

 on habits was included. The detailed studies currently being conducted on the 

 larger mammals are noteworthy. Federal and state funds have been made available 

 for these researches. In 1949, thirty-four states were engaged in deer research 

 alone. While duplication of effort is inevitable in such widespread investigations, 

 the end results may well justify these many studies. 



Many notable contributions have been made on the life history of a single 

 species, but in the present brief summary, mention can be made of only a few. 

 Paul Errington's muskrat studies are of major import. His principal objective 

 has been to fathom the rules of order governing the distribution and maintenance 

 of populations in different types of habitat. The studies of Lee R. Dice, of the 

 University of Michigan, and his students, notably W. Frank Blair, on speciation 

 in Peromyscus indicate the value of long-time research on a single genus. The 

 laboratory studies of Dice support the keen taxonomic judgment of the late Wil- 

 fred Osgood, whose revision of the genus is an unparalleled systematic study. 



The present trend is not so much an effort to catalogue the details of a par- 

 ticular species, but rather to attempt interpretations in the light of relationships. 

 We must now inquire into the "why" rather than solely occupying ourselves with 

 observed facts. A classic account of field observation has been the documentation 

 of the behavior of the red deer (Darling, 1937). This report should be studied by 

 all naturalists. The publication of Charles Elton's Animal Ecology in 1927 lent 

 great impetus to the study of population dynamics. Presently a score of American 

 investigators are following his leadership in this important field. The development 

 of banding or marking animals so that they might be recognized when recaptured 

 has been of inestimable value in determining many biological features. This sub- 

 ject, together with territorialism, was first studied among the birds by H. E. 

 Howard. The initial studies on mammals in this field were made by W. H. Burt, 

 of the University of Michigan. 



Systematic mammalogy has undergone a marked change in the century under 

 review. Earlier taxonomists were content to describe a new species in a few 

 hundred words, expressing little concern for the relationships that existed between 

 the new form and its close relatives. The concept of modern taxonomy rests in an 

 expression of relationship, based on the study of large series and firsthand knowl- 

 edge of the habitat in which the species lives. An excellent example is the recent 

 study of the harvest mice by Hooper (1952) . 



The American Society of Mammalogists 



The early interest in ornithology and entomology may, in a measure, be at- 

 tributed to several factors. Their subjects attract the eye, they are everywhere to 

 be seen, and their great variety and the relative ease of collecting them attracts 

 the young naturalist. The making of collections and the exchange of specimens 

 has had a stimulating effect on the development of natural history in North 

 America. We have seen how the development of the snap-back trap had a salu- 

 tary effect on the growth of mammalogy. The time was ripe for the organization 

 of a society, the function of which would be to encourage interest in mammals and 

 provide a means for the publication of original research. Botanical, entomo- 

 logical, and ornithological societies were flourishing in the early years of the 



