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Our Work

Our work has emphasized mechanisms of behaviour in groups. We have studied social networks and how the social environment influences individual behaviour.

Our work mostly falls into three broad categories:

Social Interaction Networks (SINs)

We have found that the social interaction patterns of flies are reproducible. Given our ability to identify and track individual flies, we have discovered that when 12 flies are placed in a simple arena, they organize themselves into a particular social interaction pattern. The specific pattern varies by fly strain, which suggests that genes contribute to the structure of these interaction networks.

Each group of flies may consist of sub-networks, or subsets of the group that have interaction patterns that give rise to the overall pattern. Flies move from one sub-network to another depending on the flies with whom they are interacting and the structure of the interaction, be it simple proximity, mating or aggression Our lab is currently seeking to identify the genes that contribute to the functioning of these networks and to learn more about life within these social groups.

We are also examining a broad range of dipteran species to gain insight into whether and how group structures are evolving.

Our lab is also developing tests that will help us to assess the flow of information between and among these networks.

Perception and Recognition of Others in the Group

The Levine Lab has demonstrated that on average, the frequency of mating throughout a 24 hour interval depends on the number of flies in the test group and on the genetic composition of the group. Throughout the day, flies in groups mate more frequently than pairs of flies. When we examine flies in groups of mixed genotypes – those where the flies have different sets of genes — we find that they mate more frequently than flies of the same genotype – those with the same genes — in same-sized groups.

Our lab and others have demonstrated that a variety of senses are employed as these group dynamics play out. Flies, like other insects, rely on chemical signals to identify species, sex, and group membership. But they also rely on touch, sight, and hearing to decode and respond to their environments.

In current studies, we are investigating what flies know about their social environment and how they know it.

Biological Clocks

Biological clocks have been a part of the repertoire of life throughout evolutionary history: prokaryotes, plants, fungi, and animals all claim timing mechanisms as part of their toolkit for meeting the needs of the day. The Levine lab has shown that one of these biological clocks has an impact on social behaviour in flies.

The more complex, multi-cellular animals and insects use a distributed system of clocks that operate in a variety of tissues. These clocks help animals enhance synchrony, respond efficiently and anticipate environmental opportunities. These opportunities could relate to the availability of food or mates. Each organism also has daily patterns of foraging and feeding and mating and sleeping that suit the lifestyle of the given in organism in its niche.

When it comes to flies, our lab has demonstrated that a clock in the brain communicates with a clock in a peripheral tissue that makes chemical signals to co-ordinate and adjusts mating frequency. A single neuropeptide, or short chain of amino acids, and its receptor are responsible for decreasing mating frequency in males and increasing frequency in females. In other words, the timing system modulates social behaviour.