590.9 193 



VI. 



ZoolooT since Darwin. 



WE younger men, whose scientific education begins under the 

 jurisdiction of Darwin, can reahse only with difficulty the ex- 

 citement which his work on the origin of species- caused almost 

 forty years ago in the realm of the natural sciences. It fell like a 

 thunderbolt during a period of calm descriptive work, a period which 

 had accustomed itself to regard the natural-philosophy ideas of the 

 beginning of the century as unproved and unprovable sports of fancy, 

 and which, therefore, mistrusting all speculation, clung anxiously to 

 the foundation of fact. What life the selection theory brought into 

 dry description, adding wings to the anatomist's knife, and opening 

 out an extensive horizon before the short-sighted eyes of the syste- 

 matist ! Round the mummies of species, well fenced-in from one 

 another by cleverly-composed Latin diagnoses, the bond of blood- 

 relationship was suddenly drawn. The fossil remains of extinct forms, 

 till then debarred from participation in existence, acquired flesh and 

 blood, and demanded to be classed with the present-day fauna and 

 flora in a single ancestral line representing the story of life on earth. 



It is universally known that the idea of a natural genealogical 

 descent of the present animal and vegetable world from the simplest 

 primordial being was suggested long before Darwin's time, and was 

 formulated in detail by Lamarck. 3 But the selection theory of the 

 celebrated Englishman, Darwin, first based the idea upon a scientific 

 foundation. The obvious phenomena of heredity and of variability 

 are the foundations of his bold system, the axles of life's mechanism ; 

 and the motive power of this mechanism is the struggle of all living 

 things for the preservation and procreation of life. The origin of the 

 millions of varieties with their different forms, all adapted to special 

 purposes, Darwin has made comprehensible by showing that the 

 preservation of the individual, as well as of the species, entails a 

 continual fight with life-conditions and with competing individuals — a 

 fight in which that only can survive v.'hich best corresponds to, and 



1 Lecture delivered by Ludwig von Graft" at his formal installation as Rector 

 Magnificus of the K. K. Karl-Franzens University in Graz, November 4, 1895. 



'^ " The Origin of Species." By Charles Darwin. Translated by J. V Carus 

 ■under the title, " Charles Darwin iiber die Entstehung der Arten." Stuttgart, 1859. 



" J. Lamarck, " Philosophic zoologique." Paris, 1809. Translated by A. Lang 

 under the title " Zoologische Philosophie von Jean Lamarck." Jena, 1876. 



P 



