Question

Phisiological digestion of wood in insect

Answer 1

THE digestion of wood in insects, and consequently the fate of cellulose, has proved

to be a prolific field for speculation. Wood-feeding insects are generally of a fairly

small size, which does not permit a thorough study of their digestive processes.

For this reason perhaps the literature dealing with the physiology of their nutrition

is very scanty. Moreover, the problem is made more difficult to settle owing to the

presence of micro-organisms, with intimate relations to the alimentary canal, in a

number of these insects. An important rdle in the digestion of wood has been

assigned to these micro-organisms, and the symbiotic relations between wood-

feeding insects and bacteria or yeasts have often been quoted. Uvarov (1929), in his

interesting summary of the literature on insect nutrition and metabolism, writes:

"the admission of the role of micro-organisms in the nutrition of wood-eating

insects clears the way to a better understanding of their physiology" (p. 266). The

same author admits clearly that all the evidence in favour of this view is indirect,