Serotonin Mediates Behavioral Gregarization Underlying Swarm Formation in Desert Locusts

@article{Anstey2009SerotoninMB,
  title={Serotonin Mediates Behavioral Gregarization Underlying Swarm Formation in Desert Locusts},
  author={Michael L. Anstey and Stephen M Rogers and Swidbert R. Ott and Malcolm Burrows and Stephen James Simpson},
  journal={Science},
  year={2009},
  volume={323},
  pages={627 - 630}
}
Desert locusts, Schistocerca gregaria, show extreme phenotypic plasticity, transforming between a little-seen solitarious phase and the notorious swarming gregarious phase depending on population density. An essential tipping point in the process of swarm formation is the initial switch from strong mutual aversion in solitarious locusts to coherent group formation and greater activity in gregarious locusts. We show here that serotonin, an evolutionarily conserved mediator of neuronal plasticity… 
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Analysis of how acute exposure to three gregarizing stimuli—crowding, touching the hind legs or seeing and smelling other locusts—and prolonged group living affect the expression of serotonin in individual neurons in the thoracic ganglia reveals a two-tiered role of the serotonergic system as both initiator and substrate of socially induced plasticity.
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Acute and chronic gregarisation are associated with distinct DNA methylation fingerprints in desert locusts
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The results indicate that changes in DNA methylation associated with behavioural gregarisation proceed through intermediate states that are not simply partial realisations of the endpoint states.
Locust Dynamics: Behavioral Phase Change and Swarming
TLDR
A partial integrodifferential equation model is constructed incorporating the interplay between phase change and spatial movement at the individual level in order to predict the dynamics of hopper band formation at the population level, and quantifies the temporal dynamics of each phase.
The Neurobiology of a Transformation from Asocial to Social Life During Swarm Formation in Desert Locusts
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There is emerging evidence that the neuronal mechanisms underlying this transformation in locusts show similarities with those underlying social behaviours in other animals, and this analysis of phase change provides insights into a feedback circuit between the environment and the neurobiology of social interaction.
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