Matuszewski Szymon, MĄdra-Bielewicz Anna
Laboratory of Criminalistics, Adam Mickiewicz University, Poznań 61-809, Poland.
Wielkopolska Centre for Advanced Technologies, Adam Mickiewicz University, Poznań 61-614, Poland.
Curr Zool. 2021 Dec 17;68(6):645-656. doi: 10.1093/cz/zoab100. eCollection 2022 Dec.
Large carrion is inhabited by highly variable and interactive communities of insects. Positive interactions in carrion insect communities have been recently the focus in carrion ecology. In contrast, competition between carrion insects is rather undervalued. Here we provide evidence that blow flies (Calliphoridae) and beetles (Silphidae), dominant decomposers of large carcasses in terrestrial habitats, compete over carrion. By reanalyzing the results from 90 pig carcasses, we demonstrated that the contribution of the flies and the beetles to the decay was negatively related. The greater part of the large carrion pool was monopolized by blow flies, whereas beetles abundantly colonized carcasses, on which blow flies were less effective as decomposers. In behavioral assays, we found that adult beetles killed 4 times more frequently feeding than postfeeding third instar larvae of the flies, with the large decrease in the killing frequency after the larvae reached the age of early third instar. Therefore, adult beetles preferentially killed the larvae that were before or in their peak feeding. The study provides evidence that the interaction between blow flies and beetles is a combination of indirect exploitative effects of the flies and direct interference effects of the beetles (the mixed competition).
大型腐肉上栖息着高度多样化且相互作用的昆虫群落。腐肉昆虫群落中的积极相互作用近来已成为腐肉生态学的研究重点。相比之下，腐肉昆虫之间的竞争却相当被低估。在此，我们提供证据表明，陆生栖息地大型尸体的主要分解者——丽蝇（丽蝇科）和埋葬虫（埋葬虫科）会争夺腐肉。通过重新分析来自90头猪尸体的结果，我们证明了丽蝇和埋葬虫对尸体腐烂的贡献呈负相关。大型腐肉资源的大部分被丽蝇占据，而埋葬虫大量聚集在丽蝇作为分解者效率较低的尸体上。在行为测定中，我们发现成年埋葬虫杀死正在取食的丽蝇幼虫的频率比取食后的三龄幼虫高出4倍，且幼虫进入三龄初期后，这种杀死频率大幅下降。因此，成年埋葬虫优先杀死处于取食前期或取食高峰期的幼虫。该研究提供了证据，表明丽蝇和埋葬虫之间的相互作用是丽蝇的间接剥削效应与埋葬虫的直接干扰效应的结合（混合竞争）。
