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A persistent behavioral state enables sustained predation of humans by mosquitoes.

ABSTRACT: Predatory animals pursue prey in a noisy sensory landscape, deciding when to continue or abandon their chase. The mosquito Aedes aegypti is a micropredator that first detects humans at a distance through sensory cues such as carbon dioxide. As a mosquito nears its target, it senses more proximal cues such as body heat that guide it to a meal of blood. How long the search for blood continues after initial detection of a human is not known. Here, we show that a 5 s optogenetic pulse of fictive carbon dioxide induced a persistent behavioral state in female mosquitoes that lasted for more than 10 min. This state is highly specific to females searching for a blood meal and was not induced in recently blood-fed females or in males, who do not feed on blood. In males that lack the gene fruitless, which controls persistent social behaviors in other insects, fictive carbon dioxide induced a long-lasting behavior response resembling the predatory state of females. Finally, we show that the persistent state triggered by detection of fictive carbon dioxide enabled females to engorge on a blood meal mimic offered up to 14 min after the initial 5 s stimulus. Our results demonstrate that a persistent internal state allows female mosquitoes to integrate multiple human sensory cues over long timescales, an ability that is key to their success as an apex micropredator of humans.

SUBMITTER: Sorrells TR

PROVIDER: S-EPMC9154740 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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A persistent behavioral state enables sustained predation of humans by mosquitoes.

Sorrells Trevor R TR Pandey Anjali A Rosas-Villegas Adriana A Vosshall Leslie B LB

eLife 20220512

Predatory animals pursue prey in a noisy sensory landscape, deciding when to continue or abandon their chase. The mosquito <i>Aedes aegypti</i> is a micropredator that first detects humans at a distance through sensory cues such as carbon dioxide. As a mosquito nears its target, it senses more proximal cues such as body heat that guide it to a meal of blood. How long the search for blood continues after initial detection of a human is not known. Here, we show that a 5 s optogenetic pulse of fict ...[more]

PMID: 35550041

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Dataset Information

A persistent behavioral state enables sustained predation of humans by mosquitoes.

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A persistent behavioral state enables sustained predation of humans by mosquitoes.

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