Cooperative System Amongst Lower Animals 773 



to their living there for considerable periods in the dark, their 

 vision has become reduced in intensity over that of other 

 insects.* The intensified senses of smell and of touch are the 

 somewhat compensating advantages gained. 



Second: Though the nuptial flight is still made in the air, 

 ants as a group have ceased to cultivate an aerial or semi-aerial 

 life, which, while attended by many disadvantages and dangers, 

 yet would bring them into rapid contact with many environal 

 conditions. Thus had they constructed strong nests on the 

 higher branches of trees, and along with this have secreted 

 formic acid, as well as the firm chitinous skin that most now 

 possess, it seems likely that such would have secured wider 

 dominance. This is to some extent proved by the successful 

 adoption of such by certain social wasps and bees. 



Now, in line with the physical law of action and reaction 

 already accepted by the writer as true for organisms (p. 130), 

 we would consider that the high plane reached by bees, and 

 specially by ants, has been secured tlirough long continued 

 proenvironal responses to countless stimuli, dating from the 

 period of the cretaceous or even older. This has stimulated 

 the nervous system to ever-increasing formation of more com- 

 plex molecules, along which cogitic as well as the lower ener- 

 gies could travel. So for these insects as for man cooperative 

 effort, with its increasingly more complex interconnections, 

 has given rise to ever more varied and abundant stimuli, which, 

 acting on the highly complex nerve substance, has slowly 

 started and elaborated in this new additions in the form of 

 nerve cells, of conducing nerve fibers, and even of new brain 

 centers. The final outcome has been the large and very com- 

 plex ant brain, the weight of which, in comparison to that of 

 man, has already been cited (p. 553). 



Amongst the molluscs, as with animals in general that live 

 in water, cooperative effort is feeble or scarcely existent. 



Our very imperfect knowledge of the nervous actions of 

 fishes from the social standpoint prevents any detailed study 



* That subterranean life, as a means of defense and even of aggressive per- 

 sistence, has high advantages is proved in tlie present international war, and 

 in the trench life it has evolved. 



