Data for: Butterfly foraging is remarkably synchronous in an experimental tropical macrocosm

Diel patterns in foraging activity are dictated by a combination of abiotic, biotic, and endogenous limits. Understanding these limits is important for insects because ectotherm taxa will respond more pronouncedly to ongoing climatic change, potentially affecting crucial ecosystem services. We leverage an experimental macrocosm, the Montreal Insectarium Grand Vivarium, to test the importance of endogenous mechanisms in determining temporal patterns in foraging activity of butterflies. Specifically, we assessed the degree of temporal niche partitioning among 24 butterfly species originating from the Earth’s tropics within controlled environmental conditions. We found strong niche overlap, with the frequency of foraging events peaking around solar noon for 96% of the species assessed. Our models suggest that this result was not due to the extent of cloud cover, which affects radiational heating and thus limits body temperature in butterflies. Together, these findings suggest that an endog..., Design overview
We sampled four sites in the Montreal Insectarium Grand Vivarium (MIGV) between April 6th and April 19th, 2022. Sites were selected initially to be similar in conditions but spread across the greenhouse to minimize the risk of pseudoreplication. We limited our sample to two weeks because we aimed to reduce as much as possible (i) variation in daylight conditions throughout the sampling period (Table S1) and (ii) the difference in butterfly age between samples. We performed twenty sampling cycles within five days, each cycle consisting of a two-minute point count per site (n = 80 total point counts). During each point count, we recorded foraging events observed at a site within an area of 10 m2 (n = 275 foraging events from 24 butterfly species). One observer kept track of butterflies within the point count area, with his colleague taking notes. Both observers paid attention to avoid double-counting of the same individuals during the two-minute point count. Position of th...,