Oviposition Behaviour as an Ecological Factor in Woodland Canopy Leafhoppers

Abstract

The role of female oviposition behaviour in determining the food plant preferences of phytophagous insects observed in the field is reviewed. Complex patterns of food plant relationships in leafhoppers associated with trees in Britain are discussed. Some species are polyphagous, others are oligophagous and most are monophagous. Experiments on feeding of nymphs and oviposition behaviour of adult leafhoppers give little support for theories which invoke the nymphal conditioning of food preferences and adult oviposition. Distinctive patterns of oviposition behaviour are important factors in the ecology and evolution of these insects.One of the major biological functions of adult female insects is to find a suitable habitat in which to oviposit. The oviposition site for any species must be such that the emerging offspring have a high chance of quickly finding suitable food. In phytophagous insects, this involves laying eggs on, in, or near to, suitable food plants. However, in any particular field locality, such insects are generally restricted to a relatively narrow range of plants on which they are able to feed, develop and reproduce. It is evident then that natural selection should favour the development of highly discriminative oviposition behaviour. Regrettably, it is still true that, as Schoonhoven (1968) noted ten years ago, there have been relatively few studies on oviposition compared with the great amount of work that has been devoted to feeding behaviour particularly of larval stages. This is unfortunate, since in most instances, larval stages do not have to find suitable food, but find themselves on or very near to it, as a result of the discriminating behaviour of adult females.Various recent studies have begun to reveal the complexity and importance of oviposition behaviour in insect ecology. Wiklund (1974Wiklund ( , 1975Wiklund ( , 1977 has examined the oviposition preferences of the butterflies, Papilio machaon (L.) and Leptidea sinapis (L.) and showed them in the field to have narrower ranges of oviposition plants than possible larval food plants. Also amongst butterflies Chew (1975 has made similar studies on two species of Pieris, and Gilbert (1975) has demonstrated the importance of visual and chemical stimuli in the oviposition of Heliconius. Huettel & Bush (1972) have shown that selective oviposition behaviour determines the monophagous feeding patterns of some trypetid fruit flies.Many phytophagous insects (including most Lepidoptera and Coleoptera) place

Host Selection and Larval Performance of Two Willow‐Feeding Sawflies

“…In accordance with many other investigations (Wiklund 1974, Claridge and Wilson 1978, Smiley 1978, Rausher 1979 our results show that the food plant spectra of Nematus larvae, as measured by their growth and survival, are wider than those of the ovipositing females. Our results show, moreover, that (l) in the multiple choice situation even the larvae are behaviorally more discriminating than their performance on different willows would suggest, and (2) in specialized N. salicis both food selection and performance patterns oflarvae show a closer resemblance to the oviposition selection by females than in more generalized N. pavidus.…”

Seasonal shifts in host usage in Uroleucon gravicorne (Homoptera: Aphididae) and implications for the evolution of host alternation in aphids

“…Certainly in Eriosomatinae, any advantage of complementary host growth patterns is enjoyed by spring generations; the winter host is not used at all for food in autumn, by either sexuparae (which fly t o the winter host) o r their non-feeding sexual offspring. Examples from other herbivorous insect groups suggest that oviposition preferences, adaptations for placing progeny in favourable circumstances, may often outweigh benefits of immediate optimization of diet (Claridge & Wilson, 1978;Claridge et al, 1977). The many gynoparae which fail t o locate hosts further increase the cost of moving in autumn.…”

“…However, oviposition on bird cherry provides fundatrices with easily located, high quality food, enabling very high reproductive rates in spring (Leather & Dixon,198 1). Examples from other herbivorous insect groups suggest that oviposition preferences, adaptations for placing progeny in favourable circumstances, may often outweigh benefits of immediate optimization of diet (Claridge & Wilson, 1978;Claridge et al, 1977).…”

“…Seasonal shifts between host taxa are known for several insect groups (Claridge & Wilson, 1978;Melber et al, 1981), but the superfamily Aphidoidea contains most examples. In the most familiar host-alternating (or heteroecious) life cycle, overwintering eggs and the first few spring generations occur on a woody plant, the 'primary' host.…”

ON THE QUESTION OF HOST RACES IN THE FALL WEBWORM, HYPHANTRIA CUNEA

“…Thus, for example, if a pheromone alone serves to attract males to females, gene flow among groups feeding on various host species could be extensive. Furthermore, evidence for the existence of oviposition preference based on larval conditioning in insects is meager (Jermy et al, 1968;Claridge & Wilson, 1978). We must, therefore, entertain the possibility that insects may not always behave in ways that allow them to exploit their environments in an optimal manner.…”