The neurogenetics of group behavior inDrosophila melanogaster

Abstract

Organisms rarely act in isolation. Their decisions and movements are often heavily influenced by direct and indirect interactions with conspecifics. For example, we each represent a single node within a social network of family and friends, and an even larger network of strangers. This group membership can affect our opinions and actions. Similarly, when in a crowd, we often coordinate our movements with others like fish in a school, or birds in a flock. Contributions of the group to individual behaviors are observed across a wide variety of taxa but their biological mechanisms remain largely unknown. With the advent of powerful computational tools as well as the unparalleled genetic accessibility and surprisingly rich social life of Drosophila melanogaster, researchers now have a unique opportunity to investigate molecular and neuronal determinants of group behavior. Conserved mechanisms and/or selective pressures in D. melanogaster can likely inform a much wider phylogenetic scale. Here, we highlight two examples to illustrate how quantitative and genetic tools can be combined to uncover mechanisms of two group behaviors in D. melanogaster: social network formation and collective behavior. Lastly, we discuss future challenges towards a full understanding how coordinated brain activity across many individuals gives rise to the behavioral patterns of animal societies.

Density-functional fluctuation theory of crowds

“…4. The nearly flat frustration associated with this behavior indicates that male flies are willing to surmount their natural repulsion and form higher density groups under deprivation conditions, a previously undocumented spontaneous self-organized change in collective behavior 31,32,35 . Attraction between individuals can be induced by introducing female flies.…”

Social behavior and aging: A fly model

“…Using the many behavioral assays and genetic tools available in D. melanogaster (reviewed in References 38,40,153), studies of social behavior in D. melanogaster have contributed to: identifying the structure of social networks, 154 FoxP, 169 neuroligins, 27 and neurobeachin. 170 Finally, many social behaviors are sexually dimorphic, and the basis of this dimorphism has been proposed to be in part generated by sex-specific neuronal circuits, or sex-specific modulation of a similar circuit (reviewed in Reference…”

“…melanogaster (reviewed inReferences 38,40,153), studies of social behavior in D. melanogaster have contributed to: identifying the structure of social networks,154 the ecological and evolutionary determinants of social behavior (eg, References 155-160), gene expression shifts in response to social experience (eg, References 161-164), and the underlying neural and genetic pathways of some social behaviors (reviewed in References 154,165,166). melanogaster (reviewed inReferences 38,40,153), studies of social behavior in D. melanogaster have contributed to: identifying the structure of social networks,154 the ecological and evolutionary determinants of social behavior (eg, References 155-160), gene expression shifts in response to social experience (eg, References 161-164), and the underlying neural and genetic pathways of some social behaviors (reviewed in References 154,165,166).…”

Decreased cerebral Irp‐1B limits impact of social isolation in wild type and Alzheimer's disease modeled in Drosophila melanogaster

“…14,17 Moreover, our data show that pan-neuronal Aβ42 expression induced severe locomotor performance defects, in line with previously published data, showing that pan-neuronal expression of Aβ42 as well as arctic Aβ42 mutation leads to impaired locomotor behavior. 17,47 As single housing has been shown to affect fly brain and behavior, 26,[31][32][33]48,49 the effect of housing conditions on Aβ42 expressing flies was analyzed. Indeed, we found that housing conditions had pronounced effects on the investigated phenotypes.…”

“…Social interactions in the fly were shown to affect group learning processes and collective behaviors in flies. [23][24][25][26][27] Flies were also shown to sense odors released by stressed flies, which in turn induced avoidance of these odors indicating that social interactions are of importance for an enhanced survival under potentially dangerous conditions. 28 It was further shown that social experience modulates the so-called social space between individual flies.…”