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For over a century, vector ecology has been a mainstay of vector-borne disease control. Much of this research has focused on the sensory ecology of blood-feeding arthropods (black flies, mosquitoes, ticks, etc.) with terrestrial vertebrate hosts. Of particular interest are the cues and sensory systems that drive host seeking and host feeding behaviours as they are critical for a vector to locate and feed from a host. An important yet overlooked component of arthropod vector ecology are the phenotypic changes observed in infected vectors that increase disease transmission. While our fundamental understanding of sensory mechanisms in disease vectors has drastically increased due to recent advances in genome engineering, for example, the advent of CRISPR-Cas9, and high-throughput "big data" approaches (genomics, proteomics, transcriptomics, etc.), we still do not know if and how parasites manipulate vector behaviour. Here, we review the latest research on arthropod vector sensory systems and propose key mechanisms that disease agents may alter to increase transmission. [ABSTRACT FROM AUTHOR]

Despite the ubiquitous nature of parasitism, how parasitism alters the outcome of host–species interactions such as competition, mutualism and predation remains unknown. Using a phylogenetically informed meta‐analysis of 154 studies, we examined how the mean and variance in the outcomes of species interactions differed between parasitized and non‐parasitized hosts. Overall, parasitism did not significantly affect the mean or variance of host–species interaction outcomes, nor did the shared evolutionary histories of hosts and parasites have an effect. Instead, there was considerable variation in outcomes, ranging from strongly detrimental to strongly beneficial for infected hosts. Trophically‐transmitted parasites increased the negative effects of predation, parasites increased and decreased the negative effects of interspecific competition for parasitized and non‐parasitized heterospecifics, respectively, and parasites had particularly strong negative effects on host species interactions in freshwater and marine habitats, yet were beneficial in terrestrial environments. Our results illuminate the diverse ways in which parasites modify critical linkages in ecological networks, implying that whether the cumulative effects of parasitism are considered detrimental depends not only on the interactions between hosts and their parasites but also on the many other interactions that hosts experience. [ABSTRACT FROM AUTHOR]

Aim: Determine the relative influence of geographical distance, environmental differences, and host species composition on the similarity of bat fly species composition. Location: Neotropics. Taxon: Bats (Chiroptera: Phyllostomidae) and bat flies (Diptera: Streblidae). Methods: Abundance data on bats and ectoparasites were obtained from published studies. The relative influences of environmental variation (annual precipitation, temperature seasonality, elevation, and NDVI), host species composition, and geographic distance on parasite community composition were analysed with Generalized Dissimilarity Modelling and variance partitioning. Additionally, we evaluated the influence of these environmental variables and geographic distance on host species composition. Results: Our model explains 45.3% of the variance in the dissimilarity of bat fly species. Host species composition had the most significant influence on bat fly species composition across communities, followed by environmental effects. Variance partitioning showed that host species composition explained 14.9% and environmental characteristics explained 10.3% of the variance in bat fly species dissimilarity. Geographical distance alone had a negligible effect as it accounted for only 0.007% of the variance in bat fly species composition. Host species composition was mainly influenced by geographic distance (18.0%) and secondarily by environmental variables (9.8%). The most important environmental variables influencing parasite and host species composition were annual precipitation and temperature seasonality, respectively. Main Conclusions: The lack of relationship between geographical distance and bat fly species composition may reflect either the high mobility or the high dispersal capacity of bat flies, or a combination of these. Alternatively, it could reflect a taxonomic artefact. Environmental differences seem to directly affect bat flies, as opposed to affecting them indirectly through their impact on the hosts. Our results support the fundamental role that host species composition plays in determining the species composition of highly host‐specific parasites. However, we argue that host specificity is not the only trait impacting ectoparasite species composition. [ABSTRACT FROM AUTHOR]

Abstract: Diapause‐mediated dormancy in overwintering insect eggs has rarely been studied with regard to the ecological factors controlling postdiapause development. In insects of temperate latitudes, water availability at the end of winter, in interaction with temperature, could control the resumption of development for insect stages in postdiapause quiescence. The balsam twig aphid, Mindarus abietinus Koch (Hemiptera: Aphididae), overwinters as eggs in southern Québec, Canada, on balsam fir, Abies balsamea (L.) Miller (Pinaceae), in Christmas tree plantations, where it is known as a pest. Previous work has shown that eggs of this aphid maintain low water content during winter, presumably to survive sub‐zero temperatures. Conversely, in late winter and early spring, they passively or actively absorb surrounding moisture, which is accompanied by notable changes in size, shape, and fresh mass. The primary objective here was to determine the embryonic stage at which winter diapause starts and is maintained in M. abietinus, a relatively primitive aphid. Secondly, we tested the hypothesis that free water availability to postdiapause eggs, in combination with temperatures above developmental threshold, is essential for embryonic development and hatching, by experimentally soaking field‐collected eggs in water at controlled frequencies. We observed that embryogenesis starts at the time of egg laying and stops after a few days, before the anatrepsis stage of blastokinesis is complete, when the germ band has not yet entirely immersed itself into the yolk. We also found that water surrounding overwintered eggs on fir shoots, in interaction with temperature regime, significantly increases M. abietinus egg hatching rates. Potential impacts of environmental factors such as precipitation are discussed in relation to M. abietinus egg hatching rates and potential for population growth in spring. [ABSTRACT FROM AUTHOR]

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For over a century, vector ecology has been a mainstay of vector-borne disease control. Much of this research has focused on the sensory ecology of blood-feeding arthropods (black flies, mosquitoes, ticks, etc.) with terrestrial vertebrate hosts. Of particular interest are the cues and sensory systems that drive host seeking and host feeding behaviours as they are critical for a vector to locate and feed from a host. An important yet overlooked component of arthropod vector ecology are the phenotypic changes observed in infected vectors that increase disease transmission. While our fundamental understanding of sensory mechanisms in disease vectors has drastically increased due to recent advances in genome engineering, for example, the advent of CRISPR-Cas9, and high-throughput "big data" approaches (genomics, proteomics, transcriptomics, etc.), we still do not know if and how parasites manipulate vector behaviour. Here, we review the latest research on arthropod vector sensory systems and propose key mechanisms that disease agents may alter to increase transmission., (Copyright © 2024. Published by Elsevier Ltd.)