Data from: The last of us: Social information enhances trappability in fruit flies

When facing novel conditions, animals must make decisions crucial to
survival with little precedence. Such decisions are not made in
isolation: animals collect information by observing conspecifics,
suggesting that social information may modify the population-level impact
of shifting environmental conditions. We tested the competing hypotheses
that social information could help or hinder animals to avoid an
evolutionary trap, a phenomenon often created by anthropogenic
modification. By manipulating the magnitude of a social cue, we examined
how the number of already-drowned conspecifics influenced fruit flies’
(Drosophila melanogaster) responses to vinegar traps. We found that flies
were faster to drown in traps with more conspecifics, supporting the
hypothesis that social information can facilitate maladaptive decisions.
Moreover, sex and prior mating experience drove variation in this
response: mated females had higher survival probabilities compared to
unmated females and males. This work highlights how anthropogenic change
can shift the fitness benefits of social information reliance, potentially
making evolutionary traps even deadlier.