Males and females often differ in their susceptibility and exposure to infection. Thus, they may also differ in their ability to avoid infection. The beetle, Tenebrio molitor, risks infection with cysticercoids when i...Males and females often differ in their susceptibility and exposure to infection. Thus, they may also differ in their ability to avoid infection. The beetle, Tenebrio molitor, risks infection with cysticercoids when ingesting rat feces containing eggs of the tapeworm, Hymenolepis diminuta. Previous studies demonstrated that beetles sometimes prefer infective feces suggesting that the tapeworm influences the foraging behavior of beetles. After recording beetle movement in an arena containing infective and uninfective feces for one hour, sex main effects were not significant, but the effect of sex asked in trials was significant for males. Specifically, more male beetles occurred on the uninfective bait than on the infective bait. This observation suggests that male beetles avoid infective feces, which decreases their probability of infection with H. diminuta. If the cost of infection is higher in males, then selection to avoid infective feces may act more strongly on males.展开更多
Many animals consume the feces of their conspecifics.This allo-coprophagy can have benefits,such as access to nutrients and symbionts,but also risks for consumers,mainly due to direct contact with pathogens that devel...Many animals consume the feces of their conspecifics.This allo-coprophagy can have benefits,such as access to nutrients and symbionts,but also risks for consumers,mainly due to direct contact with pathogens that develop on feces.In the European earwig Forficula auricularia,mothers and juveniles live in nests lined with their feces.This surprising habit allows juveniles to consume the feces of their siblings during family life and provides them with nutritional benefits when mothers provide low care.However,it was unclear whether earwig mothers also practice allo-coprophagy,and whether this behavior is motivated by their nutritional needs.Here,we set up four types of experimental families in which we manipulated the nutritional needs of mothers and/or juveniles and measured the effects on the production of feces by the juveniles,and the consumption of these feces by the mothers.Our results first show that fed juveniles produced more feces pellet in presence of fed compared to food-deprived mothers.We also found that,overall,about 50%of the mothers consumed juveniles feces.This consumption was both more likely and larger when the feces were produced by fed compared to food-deprived juveniles,while the proportion of feces pellets eaten was larger in food-deprived compared to fed mothers.Overall,our results reveal that allo-coprophagy involves every family member and suggest that it can have both nutritional and non-nutritional benefits for earwig mothers.Allo-coprophagy could thus favor the maintenance of mothers in the nest and,more generally,promote the early evolution of family life.展开更多
文摘Males and females often differ in their susceptibility and exposure to infection. Thus, they may also differ in their ability to avoid infection. The beetle, Tenebrio molitor, risks infection with cysticercoids when ingesting rat feces containing eggs of the tapeworm, Hymenolepis diminuta. Previous studies demonstrated that beetles sometimes prefer infective feces suggesting that the tapeworm influences the foraging behavior of beetles. After recording beetle movement in an arena containing infective and uninfective feces for one hour, sex main effects were not significant, but the effect of sex asked in trials was significant for males. Specifically, more male beetles occurred on the uninfective bait than on the infective bait. This observation suggests that male beetles avoid infective feces, which decreases their probability of infection with H. diminuta. If the cost of infection is higher in males, then selection to avoid infective feces may act more strongly on males.
文摘Many animals consume the feces of their conspecifics.This allo-coprophagy can have benefits,such as access to nutrients and symbionts,but also risks for consumers,mainly due to direct contact with pathogens that develop on feces.In the European earwig Forficula auricularia,mothers and juveniles live in nests lined with their feces.This surprising habit allows juveniles to consume the feces of their siblings during family life and provides them with nutritional benefits when mothers provide low care.However,it was unclear whether earwig mothers also practice allo-coprophagy,and whether this behavior is motivated by their nutritional needs.Here,we set up four types of experimental families in which we manipulated the nutritional needs of mothers and/or juveniles and measured the effects on the production of feces by the juveniles,and the consumption of these feces by the mothers.Our results first show that fed juveniles produced more feces pellet in presence of fed compared to food-deprived mothers.We also found that,overall,about 50%of the mothers consumed juveniles feces.This consumption was both more likely and larger when the feces were produced by fed compared to food-deprived juveniles,while the proportion of feces pellets eaten was larger in food-deprived compared to fed mothers.Overall,our results reveal that allo-coprophagy involves every family member and suggest that it can have both nutritional and non-nutritional benefits for earwig mothers.Allo-coprophagy could thus favor the maintenance of mothers in the nest and,more generally,promote the early evolution of family life.
