The Evolution of Parental Care 43 



was brought about by the extension of care for eggs 

 to what comes out of the eggs. Little more than a 

 feeble beginning of such an extension occurs among 

 some of the arachnids to which we have already al- 

 luded. In most insects, although provision for the 

 eggs is common, the parents, with rare exceptions, 

 are utterly indifferent to their young. Among the 

 social insects, however, such as the ants and bees, the 

 young grubs are tended with scrupulous care. In 

 the solitary bees and in many of the more primitive 

 social species the eggs are laid with sufficient pro- 

 visions for the entire life of the larvae and then left 

 without further attention. The transition from this 

 condition to one in which food is brought to the cells 

 after the larvae are hatched is an easy and natural 

 development. And as we pass to the more highly 

 developed social groups such as the hive bees the 

 instincts for taking care of the larvae become more 

 specialized and more complex. 



Among the various species of fishes that bestow 

 some care upon their eggs there are some forms that 

 pay no particular attention to their newly hatched 

 young which scatter as soon as they emerge from the 

 coverings of the eggs. In other cases such as the dog- 

 fish Amia the protecting instinct is extended to the 

 young brood. The male parent swims about with his 

 school of small fry and keeps many enemies at a 

 safe distance, for he is an alert and valiant defender 

 of his own. In the course of a few weeks, however, 

 the family ties are broken, the little fishes become 



