ROLE OF ETHOLOGY 245 



We do not yet know why or how these congregations take place 

 with any single marine animal, in the same sure kind of way that 

 we have this knowledge of some land animals. 



Now, a man can go from one end of a street to the other in 

 many ways. He can be pushed or pulled, run, skip, leap, or dance 

 down it ; he can be blown down it by wind or blast or carried down 

 by flood; his motives in going down it may be due to attraction, 

 repulsion, or compulsion; if these motives are powerful enough, as 

 in battle, he may exert sufficient effort in this act of passage to go 

 to his death; and lastly, if he is a whole man the sensory factors 

 guiding him down the street will be very different from those he 

 would use if he were blind or deaf. 



Out of this very small catalogue of causes, some are clearly 

 beyond his control, others are partly within his control, and 

 others are the result of his own choice, operated through a per- 

 ceptual field. Normally, his journeys down the street wull be the 

 latter, and the others would have no real bearing, or if they had, 

 could be analyzed and assessed. 



There is no reason why it should not be the same with animals 

 in the sea. At certain stages, or for some transient physical reason, 

 animals whether adult or larval may be forced from place to 

 place by forces beyond their control ; but for the most part the 

 movements of importance to them are directive (not necessarily 

 "goal-seeking" as some ethologists would have it), the result of 

 attraction, repulsion, or compulsion, occasioned and maintained 

 by perceptual data. The study of these factors, whether instinctive 

 or learned, is part of ethology. 



It is wasteful at this stage of the development of the science of 

 oceanography to continue to formulate hypotheses of an ecological 

 nature without first establishing their ethological basis. Dr. Verwey 

 (1959) gave close consideration to some of these factors and sum- 

 marized present knowledge of both passi^•e transportation and 

 active displacement of marine animals, relating his obser\ations 

 to behavioral data, so far as they are available. He dealt with a 

 wide range of organisms and with some of the hypotheses about 

 those migrations which contribute toward the congregation of 

 animals in certain places and in certain ways. But he did not deal 

 with one of the most striking aspects of these and that is the char- 



