How variation in temperature and diet affect adult lifespan of the yellow mealworm beetle, Tenebrio molitor L (Coleoptera: Tenebrionidae)

Abstract

As Earth warms and human populations soar, the yellow mealworm beetle, Tenebrio molitor, may prove an invaluable alternative to mainstream food sources. The current study evaluates feasibility of maintaining T. molitor adults on a simplified, reduced water-footprint diet and at two ambient temperatures. Pupae were isolated (i.e., one pupa/vial) and assigned to one of four temperature and diet treatments. Adult lifespan generally declined at the higher temperature (30 °C) and with simplified diet. Unlike higher temperature, however, simplified diet did not consistently reduce lifespan, as female longevity on standard oats-and-carrot diet did not differ from that of females limited to only oats at 30 °C. While others have noted importance of temperature and (separately) diet, this study is the first to quantify relative effects of two major environmental variables—ambient temperature together with diet—affecting mealworm cultivation. The current findings are discussed in light of large-scale insect farming and global climate change.