Wang Yin, Rozen Daniel E
Institute of Biology Leiden University Leiden The Netherlands.
Ecol Evol. 2018 Jan 5;8(3):1646-1654. doi: 10.1002/ece3.3589. eCollection 2018 Feb.
Carrion beetles, are reared on decomposing carrion where larvae are exposed to high populations of carcass-derived bacteria. Larvae do not become colonized with these bacteria but instead are colonized with the gut microbiome of their parents, suggesting that bacteria in the beetle microbiome outcompete the carcass-derived species for larval colonization. Here, we test this hypothesis and quantify the fitness consequences of colonization with different bacterial symbionts. First, we show that beetles colonized by their endogenous microbiome produce heavier broods than those colonized with carcass-bacteria. Next, we show that bacteria from the endogenous microbiome, including and , are better colonizers of the beetle gut and can outcompete nonendogenous species, including and , during in vivo competition. Finally, we find that and provide beetles with colonization resistance against and thereby reduce -induced larval mortality. This effect is eliminated in larvae first colonized by , suggesting that while competition within the larval gut is determined by priority effects, these effects are less important for -induced mortality. Our work suggests that an unappreciated benefit of parental care in is the social transmission of the microbiome from parents to offspring.
埋葬虫在腐烂的尸体上饲养，其幼虫会接触到大量源自尸体的细菌。幼虫不会被这些细菌定殖，而是被其父母的肠道微生物群定殖，这表明甲虫微生物群中的细菌在幼虫定殖方面比源自尸体的物种更具竞争力。在此，我们检验这一假设，并量化不同细菌共生体定殖对适应性的影响。首先，我们发现由其内源性微生物群定殖的甲虫所产的卵块比用尸体细菌定殖的甲虫所产的更重。其次，我们表明内源性微生物群中的细菌，包括[具体细菌1]和[具体细菌2]，是甲虫肠道更好的定殖者，并且在体内竞争期间能够胜过非内源性物种，包括[具体细菌3]和[具体细菌4]。最后，我们发现[具体细菌1]和[具体细菌2]为甲虫提供了对[具体细菌3]的定殖抗性，从而降低了由[具体细菌3]引起的幼虫死亡率。在首先被[具体细菌4]定殖的幼虫中这种效应消失了，这表明虽然幼虫肠道内的竞争由优先效应决定，但这些效应对于由[具体细菌]引起的死亡率不太重要。我们的研究表明，埋葬虫亲代抚育一个未被重视的益处是微生物群从亲代向子代的社会传递。
