Search results for "Host-parasite interactions"
showing 10 items of 330 documents
Intestinal distribution and fecundity of two species ofDiplostomumparasites in definitive hosts
2005
This paper investigated the intestinal distribution and fecundity of 2 species ofDiplostomumparasites,D. spathaceumandD. pseudospathaceum, in 2 species of definitive hosts, herring gull (Larus argentatus) and common gull (L. canus), using both empirical field data and experimental infections. At the level of individual hosts, the parasite species occupied different parts within the intestine, but the fecundity of the worms, measured as the number of eggs in the uterus, did not differ between the parasite species except in wild common gulls. Interestingly, egg numbers in individual hosts were positively correlated between the parasite species suggesting that some birds provided better resour…
Intraguild interactions between two egg parasitoids of a true bug in semi-field and field conditions.
2014
International audience; Research on interspecific competitive interactions among insect parasitoids has often been characterized by laboratory studies in which host insects are exposed to female parasitoids of different species in various sequences and combinations. In the last years, an increasing number of studies have investigated interspecific interactions under field and semi-field conditions although just a few number of works focused on egg parasitoids. In this work, we undertook a two-year study to investigate interspecific interactions between Trissolcus basalis (Wollaston) (Hymenoptera: Platygastridae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), two egg para…
Data from: Divergent ectoparasite infections in sympatric cichlid species in Lake Victoria
2018
Parasitism has been proposed as a factor in host speciation, as an agent affecting coexistence of host species in species rich communities, and as a driver of post-speciation diversification. Young adaptive radiations of closely related host species of varying ecological and genomic differentiation provide interesting opportunities to explore interactions between patterns of parasitism, divergence and coexistence of sympatric host species. Here, we explored patterns in ectoparasitism in a community of 16 fully sympatric cichlid species at Makobe Island in Lake Victoria, a model system of vertebrate adaptive radiation. We asked if host niche, host abundance or host genetic differentiation ex…
Data from: Collective defence portfolios of ant hosts shift with social parasite pressure
2014
Host defences become increasingly costly as parasites breach successive lines of defence. Because selection favours hosts that successfully resist parasitism at the lowest possible cost, escalating coevolutionary arms races are likely to drive host defence portfolios towards ever more expensive strategies. We investigated the interplay between host defence portfolios and social parasite pressure by comparing 17 populations of two Temnothorax ant species. When successful, collective aggression not only prevents parasitation but also spares host colonies the cost of searching for and moving to a new nest site. However, once parasites breach the host's nest defence, host colonies should resort…
Data from: Quality attracts parasites: host condition-dependent chemo-orientation of trematode larvae
2014
1. Environmental factors impairing physiological condition of organisms are assumed to predispose them to parasite infections. This is because host immune function is typically condition-dependent. However, poor physiological condition has been reported to reduce host susceptibility to parasites in various systems. 2. We examined whether such an effect can be due to altered exposure of hosts to active parasite transmission stages by investigating chemo-orientation of free-swimming cercariae larvae of a parasite Echinoparyphium aconiatum towards its snail host Lymnaea stagnalis. 3. We used both long-term and short-term feeding treatments to manipulate the body condition and physiological tra…
Patterns of trunk spine growth in two congeneric species of acanthocephalan: investment in attachment may differ between sexes and species.
2012
SUMMARYAcanthocephalans have evolved a hooked proboscis and some taxa have trunk spines to attach to their definitive hosts. These structures are generated before being used, thus a key question is how investment in attachment could optimally be allocated through the ontogeny. The number and arrangement of hooks and spines are never modified in the definitive host, but it is unclear whether these structures grow during adult development. A comparison of the size of trunk spines between cystacanths and adults of Corynosoma cetaceum and C. australe indicated that spines grow in both species, but only in females, which also had significantly larger spines than males. This sexual dimorphism did…
Dual action of phosphonate herbicides in plants affected by herbivore—Model study on black bean aphid Aphis fabae rearing on broad bean Vicia faba pl…
2008
Abstract The interactions between plants, herbicides and herbivore insects were studied as an aspect of possible side effect of the using of phosphonate herbicides. The experimental system was composed of phosphonate herbicides, broad bean Vicia faba (L.) plants and black bean aphid Aphis fabae (Scopoli). Two means of herbicide application, namely standard spraying and direct introduction of the herbicide into stem via glass capillary, were examined. The results obtained for N-2-piridylaminomethylene bisphosphonic acid and its derivatives show 10 times higher inhibition of the plant growth if glass capillary mode was used. When plants were infested by aphids 24 h after the use of herbicide,…
Parasite avoidance behaviours in aquatic environments
2018
Parasites, including macroparasites, protists, fungi, bacteria and viruses, can impose a heavy burden upon host animals. However, hosts are not without defences. One aspect of host defence, behavioural avoidance, has been studied in the terrestrial realm for over 50 years, but was first reported from the aquatic environment approximately 20 years ago. Evidence has mounted on the importance of parasite avoidance behaviours and it is increasingly apparent that there are core similarities in the function and benefit of this defence mechanism between terrestrial and aquatic systems. However, there are also stark differences driven by the unique biotic and abiotic characteristics of terrestrial …
Sensitivity of bipartite network analyses to incomplete sampling and taxonomic uncertainty
2023
Bipartite network analysis is a powerful tool to study the processes structuring interactions in ecological communities. In applying the method, it is assumed that the sampled interactions provide an accurate representation of the actual community. However, acquiring a representative sample may be difficult as not all species are equally abundant or easily identifiable. Two potential sampling issues can compromise the conclusions of bipartite network analyses: failure to capture the full range of interactions (sampling completeness) and use of a taxonomic level higher than species to evaluate the network (taxonomic resolution). We asked how commonly used descriptors of bipartite antagonisti…
Phosphorus limitation enhances parasite impact: feedback effects at the population level
2014
Background Nutrient deficiency affects the growth and population dynamics of consumers. Endoparasites can be seen as consumers that drain carbon (C) or energy from their host while simultaneously competing for limiting resources such as phosphorus (P). Depending on the relative demands of the host and the parasite for the limiting nutrient, intensified resource competition under nutrient limitation can either reduce the parasite’s effect on the host or further reduce the fitness of the nutrient-limited host. So far, knowledge of how nutrient limitation affects parasite performance at the host population level and how this affects the host populations is limited. Results We followed the popu…