Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway.
Section for Genetics and Evolutionary Biology, University of Oslo, Blindernveien 31, 0316 Oslo, Norway.
Proc Biol Sci. 2022 Feb 9;289(1968):20212622. doi: 10.1098/rspb.2021.2622. Epub 2022 Feb 2.
Biological communities within living organisms are structured by their host's traits. How host traits affect biodiversity and community composition is poorly explored for some associations, such as arthropods within fungal fruit bodies. Using DNA metabarcoding, we characterized the arthropod communities in living fruit bodies of 11 wood-decay fungi from boreal forests and investigated how they were affected by different fungal traits. Arthropod diversity was higher in fruit bodies with a larger surface area-to-volume ratio, suggesting that colonization is crucial to maintain arthropod populations. Diversity was not higher in long-lived fruit bodies, most likely because these fungi invest in physical or chemical defences against arthropods. Arthropod community composition was structured by all measured host traits, namely fruit body size, thickness, surface area, morphology and toughness. Notably, we identified a community gradient where soft and short-lived fruit bodies harboured more true flies, while tougher and long-lived fruit bodies had more oribatid mites and beetles, which might reflect different development times of the arthropods. Ultimately, close to 75% of the arthropods were specific to one or two fungal hosts. Besides revealing surprisingly diverse and host-specific arthropod communities within fungal fruit bodies, our study provided insight into how host traits structure communities.
生物体内的生物群落是由其宿主的特征构成的。然而，对于某些生物群落，如真菌果实体内的节肢动物，宿主特征如何影响生物多样性和群落组成仍未得到充分探索。本研究采用 DNA 宏条形码技术，对来自北方森林的 11 种木质腐朽真菌活体果实内的节肢动物群落进行了特征描述，并调查了不同真菌特征如何影响节肢动物群落。结果表明，表面积与体积比越大的果实体内的节肢动物多样性越高，这表明定植对维持节肢动物种群至关重要。寿命较长的果实体内的多样性并不高，这很可能是因为这些真菌投入了更多的物力和化学资源来抵御节肢动物。节肢动物群落的组成受到所有宿主特征的影响，包括果实体大小、厚度、表面积、形态和韧性。值得注意的是，我们鉴定出了一个群落梯度，其中柔软且寿命短的果实体内栖息着更多的真蝇，而坚韧且寿命长的果实体内则栖息着更多的食菌甲螨和甲虫，这可能反映了节肢动物不同的发育时间。最终，接近 75%的节肢动物仅存在于一到两种真菌宿主中。除了揭示真菌果实体内存在惊人多样且具有宿主特异性的节肢动物群落外，本研究还深入了解了宿主特征如何构建群落。
