THE PURPOSES OF BEHAVIOUR 133 



etc., congregate in particular regions of shallow sea bottom to 

 spawn. And so on. (2) Nesting and sheltering. Here we may 

 note the nests of salmon, sticklebacks and other fishes ; the 

 burrows of many insects ; the hives of bees, wasps and ants ; 

 the nests of birds ; the burrows, warrens and lairs of many 

 mammals ; the cocoons of silkworms and hosts of marine in- 

 vertebrates ; the choice of hosts by parasitic animals ; the 

 deposition of eggs by the parents in host-animals. And so on. 

 (3) Courtship. The highly complex activities of birds and 

 mammals that involve song, gesture, etc., in the finding of mates ; 

 behaviour of bees and wasps, etc. (4) Nurture. Carrying the 

 young in brood-pouches, etc. ; suckling the young ; feeding 

 nestling birds, etc. ; deposition and attachment of the eggs ; 

 the provision of food materials — and a host of other curious 

 activities. 



47^. Manifestations of the Urge of Individual Self- 

 preservation. Such are flight from danger ; fighting in self- 

 defence ; concealment in natural cover, or by " smoke-screens " 

 (the "' ink " of the cuttle-fish), or by imitation, or by feigning 

 death by absolute immobility — and so on : there are a multi- 

 tude of adaptations all directed to self-defence. Racial preserva- 

 tion may be included here since the parental generation " leans 

 over the offspring." Again, a multitude of behaviour-activities 

 are included in the general category of parental defence of the 

 offspring. 



47^. The Elements and Patterns of Behaviour. A 

 behaviouristic activity that manifests an urge is, as a rule, a 

 complex train of bodily movements. Thus an animal hunting 

 for food becomes aware of the prey via the stimulation of the 

 distance-receptors (smell and vision). Adapted movements of 

 pursuit, etc., are the anticipatory parts of the train of movements, 

 which are finally consummated in the killing and eating of the 

 prey. Thus we decompose such a behaviouristic activity into 

 elements : locomotion of the body in running and leaping ; move- 

 ments of the claws, jaws and teeth in killing and finally the 

 laceration and mastication and swallowing of the food. The 

 activities, locomotion, calculated approach of the prey, rending 

 motions of the claws and teeth, etc., are the elements of the activity 

 and these elements have patterns which are largely dependent 

 on the structure of the animal considered. 



