254 Morris Rockstein 



eaters had the shortest lifespans and that the total lifespan 

 was inversely proportional to the protein intake from eclosion 

 to death. 



Maurizio's work has also demonstrated the importance 

 of protein (and possibly vitamins) in the longevity of adult 

 worker honey-bees (1954). She has shown that captive 

 worker honey-bees which are fed pollen early in their adult- 

 hood resemble overwintering bees in two major respects; 

 they are longer-lived than similar bees rearing brood and, 

 secondly, their "physiological state", i.e. well-developed fat 

 body and pharyngeal glands maintained for a longer time, is 

 typical of overwintering bees (which may live as long as six 

 to eight months in contrast to six to eight weeks for maximum 

 summertime longevities). Thus, retardation of ageing in the 

 worker bee is associated with adequate pollen (protein and 

 vitamin) intake at an early adult age, in the face of reduced 

 demands upon such food reserves, such as occurs in over- 

 wintering or non-brooding "summer bees". This in turn 

 results in slow build-up and extended maintenance of those 

 structures upon which the prolongation of adult life is 

 significantly dependent. 



In all the cases mentioned above it appears that, where 

 growth or maturation has not yet been completed, an optimum 

 level of food (perhaps protein, specifically) intake is necessary 

 to complete that development. Restricting the diet, as in the 

 case of the young male white rat, trout and at least three species 

 of cockroaches, delays the attainment of adult form and con- 

 comitantly defers the cessation of growth and therefore 

 senescence. In the case of holometabolous insects, like the 

 housefly or the honey-bee, the situation is quite different. 

 These animals are essentially fully matured within a few 

 hours to several days, respectively. Heavy demands upon the 

 food (protein) reserves of the female such as oviposition in 

 the case of the housefly (Rockstein, 1958) and brood-rearing 

 in the case of the worker bee shortens the lifespan in these 

 animals. One can perhaps speak of a "negative protein 



