Data for: Aggregation in an heterospecific population of blowfly larvae: social behaviour is impacted by species-specific thermal requirements and settlement order

Larvae of several blow fly species grow on carcasses and actively aggregate together. They face harsh developmental conditions resulting in a strong pressure to reduce development time: this is achieved either through thermoregulation or aggregation. We investigate how these two developmental strategies are modulated within heterospecific groups. In the first experiment, larvae of two species with different thermal requirements were deposited simultaneously on a thermal gradient. This resulted in the formation of two monospecific groups, each located at the species-specific thermal preferendum. However, when Calliphora vomitoria (Linnaeus) larvae were placed first, the later coming Lucilia sericata (Meigen) larvae attracted the whole group to its own thermal preferendum. In the reverse experiment, a half of the replicates resulted in single dense heterospecific groups observed at temperatures ranging from C. vicina to L. sericata preferendum. The other half of the replicates resulted in..., ,