Tribolium castaneum and T. confusum are important stored grain pests, yet little is known about their life history outside the stored grain environment. Like related species, the historical habitat of T. castaneum and T. confusum is thought to be rotting logs, but current affinity and use of logs as habitat is unknown. Attraction to, survival on, and reproduction on three different species of decomposing wood was assessed for T. castaneum and T. confusum. Results indicate that both species exhibit a surprisingly high olfactory response to wood over wheat flour. Male and female beetles were equally attracted to wood, but female T. castaneum had reduced survivorship and did not oviposit on a decomposing wood substrate. These results suggest that attraction to decomposing wood is conserved across Triobolium species, yet wood itself does not fulfill critical food or reproductive substrate requirements. Flour, although less attractive than wood, does elicit a slight olfactory response, with significant reproductive capacity, which may contribute to Tribiolium’s ability to utilize this novel anthropogenic resource. This study contributes to an important yet little explored area of inquiry into the role natural microhabitats may play in supporting these economically important species and the origin of stored grain associations.

Datasets detail overall preference between wood and flour in a choice assay; reproductive output in flour versus wood; and sex specific differences in a choice assay for wood or flour. Analyses were performed in R statistical software; code is provided here for each analysis step and graphing.