to secure the most favorable amount of sunlight and at the same time successfully resist 

 unfavorable climatic conditions and enemies. The question of plant survival often hinges 

 upon the most effective methods of securing cross-pollination and seed distribution. In 

 regard to animals success in the struggle for existence may depend upon rapidity of develop- 

 ment, acute senses, strength of limb and fieetness, favorable coloration, ability to adjust them- 

 selves fully to climatic conditions, parental care, effective weapons of offense and defense, 

 mental power, etc. The result of the operation of principles one, two and three is the 

 "elimination of the unfit" and the "survival of the fittest," so far as the plants and animals 

 of a single generation are concerned. 



4. PRINCIPLE FOUR. There is a tendency to transmit by heredity to the next generation 

 those characteristics (with others as well) that have enabled the organism to attain success in 

 this life and death struggle. This is admitted to be true by all, providing these favorable 

 characteristics were themselves inherited. In case these characteristics were acquired during 

 the life of the individual, biologists are not agreed in regard to the possibility of their trans- 

 mission. Use and disuse of organs by individual plants and animals may greatly affect their 

 state of development. If continued through a series of generations it seems to the writer 

 that such characteristics will have a tendency to become fixed and transmissible. L,uther 

 Burbank has stated that all characteristics that are now inhenled must have been at some time 

 acquired. Through the operation of the entire four principles w r e may account more or less 

 satisfactorily for the remarkable adaptation of plants and animals to their environment. Il- 

 lustration of the application of these principles will be taken up in class. 



5. ARTIFICIAL SELECTION. Making use of the above described principles man steps 

 in and by eliminating the struggle and doing the selecting himself, induces Nature to produce 

 modifications that she would not otherwise make. The principles made use of are, first the 

 tendency towards variation, which may even be increased by man, and the transmi>sion of 

 inherited characteristics. The wonderful productions of Luther Burbank, such as the i horn- 

 less cactus, have been produced by careful selection, intelligent cross-pollination and the most 

 skillful treatment of the plants and their descendants. From a weed growing along the shores 

 of the Baltic (Brassica'} there has been produced the turnip, kohl rabi, cabbage, Brussels' 

 sprouts, cauliflower, etc., depending upon the storage of plant substance in the root, stem, 

 leaf or flower stalks. Beginning back in prehistoric time the domestication of animals and 

 their selection for special purposes began and is still in progress. Thus have originated our 

 various breeds of horses, cattle, sheep, dogs, cats, fowls, etc. How could man produce a blue 

 rose, a gold-fish or a white robin? 



E. Evidences of Development. There remains to be presented some of the strongest 

 evidences that the groups of plants and animals living to-day have been produced from the 

 slow modification of related groups that lived in the Ceuozoic era, rather than that they were 

 produced by the method of special creation. These ancestral groups were in their turn 

 derived from still more primitive ones owing to the slow, progressive change in the environ- 

 ment. This method is what scientists understand by development, or evolution, which is sim- 

 ply the gradual unrolling, or unfolding of a magnificaut scheme of creation which compre- 

 hends the earth itself and all that it contains. There are certain evidences that are best ex- 

 plained by assuming that the CREATOR used this method in getting the present groups of 

 plants and animals upon the earth. Taken together they have the force of a positive 

 demonstration. 



i. EVIDENCE FROM STRUCTURE. Microscopically plants and animals show a striking 

 similarity in structure, consisting of single cells, or aggregations of cells and products produced 

 thereby. Within the various groups there is strong similarity in the general plan of each 

 organism and in the more detailed plan of the various parts. A good illustration is furnished 

 by the fore limbs of the great group of vertebrates, consisting of fishes, amphibians, reptiles, 

 birds and mammals. This similarity in coarse and microscopic structure strongly suggests 

 blood relationship, the derivation of one group directly from another. It is like finding strong 

 similarity in the alphabet, words and grammar of two languages which is accepted as positive 

 evidence of direct relationship. These facts of similarity may be reconciled with the special 

 creation theory by assuming that the CREATOR simply desired to use the same plan through- 

 out his great groups, regardless of the environment that they were to occupy. This, however, 



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