666 General and Applied Biology 



a process of destroying one or more less experienced or weaker adver- 

 saries. Much is unknown about the communal life of animals, and the 

 reader is referred to additional references in this important field. After 

 Charles Darwin proposed his doctrine of the survival of the fittest, it 

 was maintained that all living animals and plants struggle for their exist- 

 ence. If this be true, then the success or failure of individuals or groups 

 may be influenced to a greater or lesser extent by their inherent abilities 

 of survival commensurate with the specific environmental factors present 

 in the area in which they live. Cooperation between individuals is ob- 

 served in the care of young by most mammals, the protection of wounded 

 and sick by many higher animals, the protection of the herd by the male 

 deer, the sharing of foods in such animals as apes and man, and the pro- 

 tection of members of a family against enemies, etc. 



V. PREDACIOUSNESS 



Predatism or predaciousness (pre -da' shus nes) (L. praeda, prey or 

 booty) is a condition in which one animal captures and preys on another 

 living organism, usually using it for food. Predatism is characteristic of 

 those animals which we term predatory which kill animals and devour 

 them for food. These predatory habits may be exhibited by a great num- 



Fig. 328. — Starfish attacking an oyster. Note the tube feet on the underside of 

 the starfish arms. (Courtesy of The American Museum of Natural History.) 



