Effects of Flour Conditioning on Cannibalism of <I>T. castaneum</I> Eggs and Pupae

Abstract

Cannibalism is a very important factor regulating population dynamics of the red flour beetle. After several days of feeding, the flour becomes conditioned by the beetles, which can affect rates of cannibalism. Flour conditioning is caused by an accumulation of feces, pheromones, and ethylquinone, which is a repellent produced by the beetles. We determined the effect of five different levels of flour conditioning on cannibalism of red flour beetle eggs and pupae by adult and larval stages. Larvae had the highest rates of egg cannibalism (12 eggs eaten over the 4-d period) followed by female adults (seven eggs consumed). Adult males had the lowest rates of cannibalism with only two eggs consumed. Cannibalism of eggs by females was correlated negatively with the level of flour conditioning. There was no effect of flour conditioning on egg or pupal cannibalism by larvae or adult males. Cannibalism by adult females may decrease as the level of flour conditioning increases because females may spend less time tunneling in highly conditioned flour and more time trying to disperse to other areas that are better for oviposition.

Reproduction of confused flour beetle Tribolium confusum Du Val (Coleoptera: Tenebrionidae) on common and spelt wheat and their products

“…This finding has been reported by many other authors as well (Alabi et al, 2008;Flinn & Campbell, 2012).…”

The red flour beetle Tribolium castaneum: A model for host-microbiome interactions

“…Finally, we find that in the absence of an intact flour microbiome, adult beetles and larvae increase egg cannibalism. Since flour beetle cannibalism typically increases in poor resources [28,30,31], we suggest that the flour microbiome may either directly or indirectly signal resource quality.…”

“…Finally, we find that in the absence of an intact flour microbiome, adult beetles and larvae increase egg cannibalism. Since flour beetle cannibalism typically increases in poor resources [ 28 , 30 , 31 ], we suggest that the flour microbiome may either directly or indirectly signal resource quality. Pathogen resistance was the only tested fitness metric where we did not find an impact of the microbiome; although prior work suggests that the beetle microbiome is critical for the formation of immune memory against the same species of pathogen used in our assays [ 16 ].…”

“…Cannibalism plays a major role in flour beetle biology [27][28][29], and cannibalism rates typically increase in poor quality resources [30,31]. Hence, we measured egg cannibalism rates as a function of normal vs. depleted flour microbiomes.…”

Birth Rate Effects on an Age-Structured Predator-Prey Model with Cannibalism in the Prey

“…An important characteristic of our proposed models is the consideration of the cannibalism effect on the prey, since several studies have reported the stabilizing consequences of cannibalism in predator-prey systems [12,13]. There are numerous examples in nature where cannibalism is present, for example, the confused flour beetle (Tribolium confusum) [14], the red flour beetle (Tribolium castaneum) [15], and the Dungeness crab (Metacarcinus magister) [16].…”