Cirtwill Alyssa R, Roslin Tomas, Peña-Aguilera Pablo, Agboto Agathe, Bercê William, Bondarchuk Svetlana N, Brodschneider Robert, Heidari Behzad, Kaizirege Camara, Nyaga Justine Muhoro, Ekpah Ojonugwa, Gomez Gonzalo Ossa, Paz Claudia, Pirk Christian, Salehi-Najafabadi Amir, Salonen Anneli, Soloniaina Chantal, Wirta Helena
Carex EcoLogics, Bracebridge, ON, Canada.
Department of Ecology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
BMC Ecol Evol. 2025 Mar 17;25(1):24. doi: 10.1186/s12862-025-02363-1.
Contrasting hypotheses suggest that the number of biotic interactions per species could either increase towards the equator due to the increasing richness of potential interaction partners (Neutral theory), or decrease in the tropics due to increased biotic competition (Latitudinal Biotic Interaction Hypothesis). Empirical testing of these hypotheses remains limited due to practical limitations, differences in methodology, and species turnover across latitudes. Here, we focus on a single species with a worldwide distribution, the honey bee (Apis mellifera L.), to assess how the number of different types of interactions vary across latitudes. Foraging honey bees interact with many organisms in their local environment, including plants they actively select to visit and microbes that they largely encounter passively (i.e., unintentionally and more or less randomly). Tissue pieces and spores of these organisms are carried to the hive by foraging honey bees and end up preserved within honey, providing a rich record of the species honey bees encounter in nature.
Using honey samples from around the globe, we show that while honey bees visit more plant taxa at higher latitudes, they encounter more bacteria in the tropics.
These different components of honey bees' biotic niche support the latitudinal biotic interaction hypothesis for actively-chosen interactions, but are more consistent with neutral theory (assuming greater bacterial richness in the tropics) for unintentional interactions.
相互矛盾的假说表明，由于潜在相互作用伙伴的丰富度增加，每个物种的生物相互作用数量可能会向赤道方向增加（中性理论），或者由于生物竞争加剧，热带地区的生物相互作用数量会减少（纬度生物相互作用假说）。由于实际限制、方法差异以及不同纬度间的物种更替，对这些假说的实证检验仍然有限。在这里，我们聚焦于一种分布在全球的单一物种——蜜蜂（西方蜜蜂），以评估不同类型的相互作用数量如何随纬度变化。觅食的蜜蜂在其当地环境中与许多生物相互作用，包括它们主动选择访问的植物以及它们在很大程度上被动遇到的微生物（即无意且或多或少随机地遇到）。这些生物的组织碎片和孢子被觅食的蜜蜂带回蜂巢，并最终保存在蜂蜜中，提供了蜜蜂在自然界中遇到的物种的丰富记录。
通过使用来自全球各地的蜂蜜样本，我们发现虽然蜜蜂在较高纬度地区访问更多的植物类群，但它们在热带地区遇到更多的细菌。
蜜蜂生物生态位的这些不同组成部分支持了关于主动选择的相互作用的纬度生物相互作用假说，但对于无意的相互作用，更符合中性理论（假设热带地区细菌丰富度更高）。
