title: Competition between species of the aestivo-autumnal group of birch pests for food in Transuralia.
abstract: The aestivo-autumnal group of birch pests includes 25 species belong to the Notodontidae, Geometridae, Noctuidae, and other families. The larvae of all its species hatch out in mid-July and feed until the end of August. On emerging from the eggs they spread from leaf to leaf, but as the food supply diminishes they crowd together and competition is intensified. The species structure of the group shows some variation over the territory, and only a few species dominate, different species in different places. It is suggested that improvement in the food supply leads to mass reproduction. Biochemical investigations confirmed this hypothesis: different species feeding on the same leaf assimilate different amino acids more completely, and their relative numbers on the leaves vary in different parts and at different times. The composition of secondary metabolites important for resistance of the plants also varies.
mesh_terms: D004463:Ecology; D007313:Insecta / Q000502:physiology*; D007814:Larva; D007915:Lepidoptera / Q000502:physiology; D008675:Metamorphosis, Biological; D010274:Parasitology; D012621:Seasons; D012800:Siberia; D013045:Species Specificity; D014197:Trees