FOOD COACTIONS 



115 



teaching of the young to fly and hunt food is among the important 

 coactions of birds. 



The gregarious habit so common among the larger mammals in 

 tundra, grassland, and savannah affords protection from enemies, 

 especially for the young, and constitutes a simple form of cooperation, 

 as in the case of the musk ox (Fig. 28). Social coactions in food 

 getting are exemplified by the wolves, which aggregate in packs for 

 community hunting in the winter and follow more or less regular 



WOLFITRAILS AND DENS 





Sfiganaga ^\ % 



Wolf Trails 



• Dens 



^^■^^ National Forest Boundary 

 I— I— I— I Main Travelled Wolf Trails 



Fig. 29. — Wolf pack routes in the Suporior-Quctico area. The long axis of 

 ellipse A is approximately 55 miles (89 kilometers), B is 95 miles (153 kilo- 

 meters), and C is 60 miles (97 kilometers). (After Olson, 1938, a, b.) 



routes that bear a close relation to dens or homes (Fig. 29). These 

 gregarious habits tend to make both reaction and coaction intensive 

 in some areas and consequently irregular in pattern. The detailed 

 descriptions of aggregation and herding in both small and large ani- 

 mals are easily available in the well-known treatise by Allee and 

 hence do not require further discussion. 



FOOD COACTIONS 



Elton (1927:56) employs the term "food chain" for a sequence of 

 such coactions and refers to all the food chains in a community as 

 the "food cycle." In view of the specialized use of the term cycle, 

 food nexe {nexus, tie, bond) appears preferable for the interwoven 



