134 ANIMAL BEHAVIOUR 



We can only illustrate these statements by summary considera- 

 tion of some elementary behaviouristic activities : 



Locomotion. There are the patterns — Quadrupedal and bipedal 

 walking, running, leaping as exhibited in the movements of 

 mammals ; Hopping in birds ; Saltatory motions of many crusta- 

 ceans ; Crawling in such different ways as the motions of a 

 millipede, or those of an Echinoderm (such as a starfish) ; Burrow- 

 ing in the soil by rabbits, moles, earthworms, etc. ; Swimming 

 in such diverse ways as by means of cilia (in protozoa), by the 

 swimmerets in a micro-crustacean, or by the fins of a fish ; Writh- 

 ing as in the locomotion of a snail or limpet (where wave-like 

 contractions of a muscular organ, or " foot " effect the loco- 

 motion) ; Rocket-propulsion as in the squid ; Gliding and flying 

 as in fishes, insects, birds and bats. And so on. 



Killing. Biting with jaws and teeth ; Biting that involves the 

 injection of poison (snakes, etc.) ; Striking with claws and 

 other bodily weapons ; Goring as in cattle and sword-fishes ; 

 Crushing as by pythons, bears and cuttle-fishes ; Stinging as in 

 the cases of bees, wasps, etc. And so on. 



We may regard behaviour in general as expressed by combina- 

 tions of the elements : locomotion with its variants ; killing ; 

 feeding, fabrication of nests and shelters ; vocalization ; the 

 specialized motions of the external genital organs in copulation 

 and so on. A certain number of such elementary activities are 

 the equipment of all animals. In the well- differentiated categories 

 of animals the patterns of the elements are different — as we 

 have indicated above. The elements are combined or integrated 

 into the behaviouristic activity that the particular occasion demands : 

 thus the activity, whatever it may be, is, as a rule, unique in each 

 higher animal, varying from example to example with the environ- 

 mental circumstances and the animals' experience. 



The patterns of the elements correspond roughly with the 

 structure. Obviously flight is impossible to a dog, stinging to a 

 butterfly and vocalization to most fishes. The evolution of the 

 structure of the body must largely restrict the bodily activities 

 and even render some impossible in particular cases. 



47^. The Versatility of Behaviour. But while structure 

 imposes such obvious limitations on what an animal may do, it 

 is not always possible to deduce the pattern of behaviour from 

 the structure. In simple cases the " behaviour " of a machine 



