Should females cannibalize with or without mating in the facultatively parthenogenetic springbok mantis?

Noncopulatory cannibalism, which occurs when females attack and consume males instead of mating with them, could persist if it increases female fecundity more than it exacerbates reproductive failure. However, females that are facultatively parthenogenetic may be able to cannibalize indiscriminately since securing a mate is not necessary for reproduction when parthenogenesis is possible. We used an experimental approach to examine the economics of cannibalism with and without mating for female Miomantis caffra, a facultatively parthenogenetic mantis that shows high rates of noncopulatory cannibalism. If noncopulatory cannibalism is maintained by fecundity enhancement, we predicted that eating a male would boost female fitness regardless of mating status. If noncopulatory cannibalism persists by facilitating total mating avoidance, then we predicted that mating would be costly, and females would perform better via parthenogenesis than via sex. Contrary to our predictions, we found that mating once led to dramatically higher fitness than not mating, and cannibalizing a single male provided no overall fitness benefit to either mated or unmated females. Our results suggest that precopulatory cannibalism persists in M. caffra for reasons other than fecundity enhancement or total mating avoidance. (c) 2023 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

Automated summary

Noncopulatory cannibalism, where females attack and consume males instead of mating, may persist if it benefits female fecundity more than it harms reproductive failure. In this study, researchers examined the economics of cannibalism with and without mating in the facultatively parthenogenetic mantis Miomantis caffra. Contrary to their predictions, mating once significantly increased fitness compared to not mating, and cannibalizing a male did not provide any fitness advantage for both mated and unmated females. Thus, precopulatory cannibalism in M. caffra may have reasons other than fecundity enhancement or total mating avoidance.