M Asmi Jezeera, N Kavya Mohan, Sreekumar Sreyas, Kelber Almut, Somanathan Hema
School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, India.
Lund Vision Group, Department of Biology, Lund University, Lund, Sweden.
Naturwissenschaften. 2025 May 30;112(3):44. doi: 10.1007/s00114-025-01994-0.
Miniaturisation can influence the foraging behaviour of flower visitors by shaping their sensory systems, flight capabilities, and their compatibility with floral shapes and structures. For bees, vision is a primary sensory modality, and a reduction in eye size compromises the resolution and sensitivity of vision. In Tetragonula iridipennis, a diminutive tropical stingless bee common in South Asia, we addressed the following questions: (a) Since flight capabilities are correlated with body size, does it largely utilise resources from understorey plants? (b) Does their small body size permit the utilisation of flowers with diverse morphologies? Further, we explored floral colour in relation to bee colour vision by examining if: (c) the distribution of marker points of the community floral spectra (n = 182 species) corresponds with bee photoreceptor sensitivities and (d) the colours of flowers visited or not visited by T. iridipennis form separate clusters in the bee colour space. We found a high degree of resource generalisation, with T. iridipennis visiting ~ 46% of flowering plant species (n = 215). However, three plant species accounted for the highest visitation rates (90%). There was no correlation between plant functional groups and foraging preferences. Floral shape and the interaction between floral area and shape significantly predicted visitation by T. iridipennis. Further studies on other bee species that are sympatric, closely related, and varying in body size will help understand the role of miniaturisation in foraging ecology of pollinators.
小型化可以通过塑造访花者的感官系统、飞行能力以及它们与花的形状和结构的兼容性来影响其觅食行为。对于蜜蜂来说，视觉是主要的感官方式，眼睛大小的减小会损害视觉的分辨率和灵敏度。在四角无刺蜂（Tetragonula iridipennis）中，这是一种在南亚常见的小型热带无刺蜂，我们提出了以下问题：（a）由于飞行能力与体型相关，它是否主要利用林下植物的资源？（b）它们的小体型是否允许它们利用具有不同形态的花朵？此外，我们通过研究以下方面来探索与蜜蜂色觉相关的花色：（c）群落花光谱（n = 182种）的标记点分布是否与蜜蜂光感受器的敏感性相对应，以及（d）四角无刺蜂访问或未访问的花朵颜色在蜜蜂颜色空间中是否形成单独的聚类。我们发现资源泛化程度很高，四角无刺蜂访问了约46%的开花植物物种（n = 215）。然而，有三种植物物种的访问率最高（90%）。植物功能组与觅食偏好之间没有相关性。花的形状以及花面积与形状之间的相互作用显著预测了四角无刺蜂的访问情况。对其他同域分布、亲缘关系密切且体型各异的蜜蜂物种进行进一步研究，将有助于了解小型化在传粉者觅食生态学中的作用。
