Aberrant Feeding Behavior Among Insects and Its Bearing on the Development of Specialized Food Habits

Abstract

ABERRANT FEEDING BEHAVIOR AMONG INSECTS AND ITS BEARING ON THE DEVELOPMENT OF SPECIALIZED FOOD HABITS BY CHARLES T. BRUES Harvard University T HE behavior of insects with relation to food is extremely diverse if we consider them as a group. Any survey of its component parts reveals at once a more or less orderly distribution of the several types of food-habits with reference to characteristic peculiarities of structure, development and instinct. The dependence of trophic behavior upon the adjustment of such intrinsic factors to the environment is obvious, and we must look for any indications of the origin and development of predatism, vegetarianism, parasitism and the like by inquiry into the interactions of these internal and external modifications. Diversity in behavior among insects is readily traceable to their extremely plastic structural organization which admits of many drastic changes in the form of bodily parts, such as the mouthparts, legs, respiratory system, wings, etc. Such structural peculiarities frequently appear without associated modifications in other structures and correspond almost invariably to changes in habits to which they are highly, often exquisitely adapted. Whatever theoretical interpretation we may apply to the origin of these adaptations, their occurrence is real and by no means infrequent. Many cases of peculiar food-relations appear to be primarily of this nature. The indirect development of the higher insects opens new avenues for the initiation of profound although transitory structural modifications in the nymphal and larval stages, since the latter are interpolated in such a way that they may develop at this time entirely novel characteristics which leave no impress upon the imago.