. Evolution and animal life; an elementary discussion of facts, processes, laws and theories relating to the life and evolution of animals . ver goon shore; but in thespring they return tothe northward, find-ing the little islandshidden in the arcticfogs, often landing onthe very spot from which they were driven by the ice six months before, andtheir arrival timed from year to year almost to the sameday. The perfection of this homing instinct is vital to theirlife. If defective in any individual, he would be lost to theherd and would leave no descendants. Those who return be-come parents of th
. Evolution and animal life; an elementary discussion of facts, processes, laws and theories relating to the life and evolution of animals . ver goon shore; but in thespring they return tothe northward, find-ing the little islandshidden in the arcticfogs, often landing onthe very spot from which they were driven by the ice six months before, andtheir arrival timed from year to year almost to the sameday. The perfection of this homing instinct is vital to theirlife. If defective in any individual, he would be lost to theherd and would leave no descendants. Those who return be-come parents of the herd. As to the others the rough seatells no tales. We know that of those that set forth a largepercentage never come back. To those that return the hominginstinct has proved adequate. This must be so long as the raceexists. The failure of instinct would mean the extinction ofthe species. The instincts of animals may be roughly classified as to theirrelation to the individual into egoistic and altruistic instincts. Egoistic instincts are those which concern chiefly the in-dividual animal itself. To this class belong the instincts of. FIG. 266.—A pointer dog in the act of point-ing, a specialized instinct. (Permission of G. , publisher of Recreation.) 432 EVOLUTION AND ANIMAL LIFE L feeding, those of self-defense and of strife, the instincts of play,the climatic instincts, and environmental instincts, those whichdirect the animals mode of life. Altruistic instincts are those which relate to parenthood and those which are concernedwith the mass of individuals ofthe same species. The lattermay be called the social the former class, with the in-stincts of parenthood, may be in-cluded the instincts of courtship,reproduction, home-making, nest-building, and care for the young. The instincts of feeding areprimitively simple, growing com-plex through complex protozoan absorbs smallercreatures which contain nutri-ment. The sea anemone closesits t
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