THE BIOLOGY OF AGEING IN INSECTS 



Morris Rockstein 



Department of Physiology, New York University College of 

 Medicine t New York 



For well over a decade the present author's interest in 

 ageing has been that of establishing firm, quantitative bio- 

 chemical criteria for physiological ageing, particularly in 

 structures manifesting senescence in the form of declining 

 function as well as degenerative anatomical alterations with 

 advancing age. As a direct consequence of these physiological 

 studies, longevity data have been obtained for large numbers 

 of individuals for each of two species of insects and for strains 

 of similar genetic constitution in each case. This discussion 

 will present details of the lifespan of the common housefly, 

 Musca domestica L., and the honey-bee, Apis mellifera L., 

 with special emphasis upon recent studies directly concerned 

 with the factors affecting the lifespan of male and female 

 houseflies. 



In an earlier series of experiments, involving a comparison 

 of change in cell number with alteration in cholinesterase 

 activity with age, in the adult worker honey-bee (Rockstein, 

 1950a), the time of final samplings of living animals was 

 determined by the availability of sufficient numbers of bees 

 for enzymological and histological evaluation. In all cases 

 this occurred when one per cent or less of the original number 

 of bees employed were still living, and represented values very 

 close to the maximum lifespan for this strain of Italian golden 

 honey-bees. Thus, for 3,750 queenless worker bees, maintained 

 indoors in large cages supplied with honey, pollen and water 

 in excess and exposed to artificial lighting day and night, the 

 final sampling was made at 68 days. A similar value of ten 



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