Egg laying by a butterfly on a fragmented host plant: a multi-level approach (original) (raw)

Variation in butterfly egg adhesion: adaptation to local host plant senescence characteristics?

Most butterflies that overwinter as diapausing eggs have evolved oviposition behaviours where egg placement is near or on perennating portions of their host plant. We describe an alternative strategy used by alpine populations of a Lycaenid butterfly species complex where eggs are not attached strongly to the leaf substrate and subsequently fall off the plant. Other populations occurring at lower elevations attach their eggs strongly to the plant. In the laboratory, we measured the amount of force required to detach eggs from the leaf substrate. Eggs of the non-alpine populations required more than five times the force required to detach eggs of the alpine population. Field surveys of the host plant characteristics used by various populations suggest that easy detachment may be adaptive for alpine populations because, unlike the host plants used by other populations, nearly all of the preceding year's vegetative growth is blown away by strong winds during the winter months.

Reproductive escape: annual plant responds to butterfly eggs by accelerating seed production

Functional Ecology, 2013

1. Plants respond to insect herbivores with changes in physical and chemical traits, both locally and systemically, in leaves and flowers. Such phenotypic changes may influence the behaviour of every community member that interacts with the plant. Here, we address effects of plant responses to eggs and subsequent herbivory by caterpillars on plant-mediated interactions with pollinators and consequences for plant fitness. 2. Using a common garden set-up, we have investigated responses of Brassica nigra plants to herbivore exposure from egg deposition onwards throughout larval development. We quantified effects of infestation by the specialist Pieris brassicae on: 1. behaviour of pollinators; 2. volatile emission and 3. timing and number of seeds produced. 3. Egg deposition and folivory did not influence visitation by pollinators to plots of infested or control plants. Effects of herbivore infestation on both pollinator visitation and volatile emission were observed only at a later stage, when caterpillars were feeding on the flowers. 4. Remarkably, before eggs had hatched, infested plants accelerated seed production. The caterpillars that developed from the eggs fed on flowers but not on seeds and thus seed production prior to herbivory on flowers safeguarded reproductive output. 5. The results of this study show that early plant investments in reproduction can successfully prevent consumption of expensive reproductive tissues. By accelerating seed production, plants prevented consumption of flowers and effectively defended themselves against the herbivores.

Insects allocate eggs adaptively across their native host plants

Arthropod-Plant Interactions, 2019

Finding plants for their eggs is the only parental care shown by many winged insects. Hatched juveniles often feed on one individual plant until gaining the power of flight as adults. Females are therefore predicted to lay more eggs on plants supporting high offspring survival. Many experiments comparing egg-laying and offspring survival across plant species refute this, leading to alternative concepts including 'enemy free space', 'optimal bad motherhood' and 'neural constraints'. Whether tested plants have the same geographic origin as the insect is often overlooked. Using 178 oviposition-performance studies, we found when insects and plants share a native range, 83% of insect species associated their eggs with plants conferring highest offspring survival. This was broadly true across insect taxa and for generalists and specialists. Only 57% did so with non-native plants. That females are attracted to hosts with high offspring survival is a well-supported theory that does not necessarily apply to exotic host plants.

Does the Small White Butterfly (Pieris rapae L.) Aggregate Eggs on Plants with Greater Gas Exchange Activity

Journal of Insect Behavior, 2001

Few studies have investigated insect egg-laying preferences in relation to photosynthesis or transpiration of their host plants. It has been suggested that intravarietal preferences of the small white butterfly (Pieris rapae L.: Pieridae) include larger plants with characteristically higher transpiration rates. Interestingly this species, like many other Lepidoptera, may detect biogenic CO2 gradients associated with photosynthesis. We studied egg-laying preferences in working farm environments examining relationships among host choice, plant gas exchange activity, and plant size. Females discriminated between plants in monocultures on the basis of height. A balance of pre- and post–alighting preferences resulted in plants of medium size receiving eggs. Post–alighting preferences led to plants, but not alighted leaves, with higher rates of photosynthesis supporting eggs. These findings do not support a mechanistic basis for the use of gas exchange activity during host selection but, for the first time, indicate the greater physiological activity of crop plants that ultimately received the eggs of a pest insect.

Inspection and evaluation of host plant by the butterfly Mechanitis lysimnia (Nymph., Ithomiinae) before laying eggs: a mechanism to reduce intraspecific competition

Oecologia, 1993

Females of Mechanitis lysimnia (Lepidoptera: Nymphalidae) show a characteristic searching, inspecting and evaluating behavior on their Solanum host plants. The average egg-clutch size for this butterfly varied with the host species of Solanum. There was a positive relationship between the egg-clutch size of M. lysimnia and the number of leaves, indicating an adjustment between the reproductive effort of the insect and the amount of food available to its offspring. Field experiments showed that butterflies were able to recognize conspecific egg-clusters by visual cues and preferred to lay eggs on egg-free host plants. On large plants that received two or more egg-clusters, later clutches contained fewer eggs than the first one. The butterflies seem to evaluate the amount of food by inspecting the quantity of leaves and by checking for presence or absence of eggs and, possibly, caterpillars before deciding if and how many eggs to lay. These behavioral mechanisms should be important in reducing direct intraspecific competition for the five rare, small and ephemeral host plant species used by this insect.

Host plant utilization in the comma butterfly: sources of variation and evolutionary implications

Oecologia, 1994

A major challenge in the study of insect-host plant interactions is to understand how the different aspects of offspring performance interact to produce a preference hierarchy in the ovipositing females. In this paper we investigate host plant preference of the polyphagous butterfly Polygonia c-album (Lepidoptera: Nymphalidae) and compare it with several aspects of the life history of its offspring (growth rate, development time, adult size, survival and female fecundity). Females and offspring were tested on four naturally used host plants (Urtica dioica, Ulmus glabra, Salix caprea, and Betula pubescens). There was substantial individual variation in host plant preference, including reversals in rank order, but the differences were largely confined to differences in the ranking of Urtica dioica and S. caprea. Different aspects of performance on these two plants gave conflicting and complementary results, implying a trade-off between short development time on U dioica, and larger size and higher fecundity on S. caprea. As all performance components showed low individual variation the large variation in host plant preference was interpreted as due to alternative oviposition strategies on the basis of similar 'performance hierarchies'. This indicates that the larval performance component of host-plant utilization may be more conservative to evolutionary change than the preference of ovipositing females. Possible macro-evolutionary implications of this are discussed.

Plants and insect eggs: how do they affect each other?

Phytochemistry, 2011

Plant-insect interactions are not just influenced by interactions between plants and the actively feeding stages, but also by the close relationships between plants and insect eggs. Here, we review both effects of plants on insect eggs and, vice versa, effects of eggs on plants. We consider the influence of plants on the production of insect eggs and address the role of phytochemicals for the biosynthesis and release of insect sex pheromones, as well as for insect fecundity. Effects of plants on insect oviposition by contact and olfactory plant cues are summarised. In addition, we consider how the leaf boundary layer influences both insect egg deposition behaviour and development of the embryo inside the egg. The effects of eggs on plants involve egg-induced changes of photosynthetic activity and of the plant's secondary metabolism. Except for gall-inducing insects, egg-induced changes of phytochemistry were so far found to be detrimental to the eggs. Egg deposition can induce h...

Leaf and Floral Parts Feeding by Orange Tip Butterfly Larvae Depends on Larval Position but Not on Glucosinolate Profile or Nitrogen Level

Journal of Chemical Ecology, 2010

In an attempt to identify chemical signals governing the general flower and silique feeding behavior of larvae of the orange tip butterfly, Anthocharis cardamines (L.), we investigated feeding behavior and chemistry of two major host plants: Cardamine pratensis L. and Alliaria petiolata (Bieb.) Cavara & Grande (garlic mustard). Larvae reportedly feed mainly on flowers and siliques rather than leaves in nature, and did so when observed on the original host plants. Behavioral experiments, using detached A. petiolata branches, however, showed that larvae readily accepted leaves and only the final instar showed a tendency for directed movement towards floral parts. To search for semiochemicals that control plant part preference and to assess possible nutritional consequences of floral parts feeding, we determined glucosinolate profiles and total nitrogen levels of floral parts and leaves. There was only moderate difference between glucosinolate profiles of leaves and floral parts within each of two host plant species. In contrast, the profiles of floral parts differed significantly between them. A. petiolata was dominated by 2-propenyl glucosinolate, while C. pratensis was dominated by aromatic glucosinolates and branched aliphatic glucosinolates, with considerable variation among populations. Nitrogen levels tended to be higher in floral parts than in leaves in A. petiolata, but not in C. pratensis, so floral feeding could not generally be attributed to higher N content. With the exception of a tendency of last instar larvae (L5) to move to the apex and ingest flowers and upper stem, we did not find either a plant chemistry basis or larval acceptance/rejection behavior that could explain the usual feeding of floral parts by orange tip larvae of all instars. However, by artificial manipulation of vertical larval position on host plants, we found that the frequency of leaf vs. flower feeding during 24 hr depended significantly on the initial larval position. Hence, we suggest that the placement of eggs on floral parts by ovipositing female butterflies is a major explanation of orange tip feeding habits previously known from field observations.

Host plant conspicuousness and the distribution of eggs and larvae in the butterfly,Anthocharis scolymus (Lepidoptera: Pieridae)

Researches on Population Ecology, 1993

We investigated how the distribution pattern of eggs and larval on the host plant, Turritus glabra, was influenced by the oviposition behavior of the pierid butterfly Anthocharis scolymus. Females searched for the host plants visually and they frequently approached taller host plants with sparse surrounding vegetation. After encountering host plants, oviposition behavior of females was independent of host plant characteristics such as height, density, and type of surrounding vegetation. A female laid eggs singly on a host plants. Most females appeared to lay their eggs regardless of the presense of eggs on the host plant. Consequently, egg and larva tended to be abundant on conspicuous host plants as measured by height or relative isolation from other plants. However, overcrowding of eggs on an individual host decreased the survival rate of larvae.