目的:刺梨是一种广泛的魅力植物,其中夜间的花卉习性与昼夜蜜蜂的高度探访和鹰蛾的明显稀缺形成鲜明对比。为了解决这种差异并阐明刺五加的花卉进化,我们分析了视觉和嗅觉线索的内部模式与不同访客行会(蜜蜂,蝴蝶,和鹰蛾)。
方法:我们测量了气味的内部变化,反射光谱,和比色特性,根据三个已知的C.spinosa访客行会。此外,我们使用运动激活相机对探视率进行采样。
结果:木匠蜜蜂访问花朵的频率是夜间活动的鹰蛾的八倍,在黄昏和第二天早上。然而,spinosa的花顶部空间含有典型的嗜鞘气味,具有高排放率的某些单萜和氨基酸衍生化合物。视觉线索包括一种特殊的多感官花蜜指南和颜色图案,这些图案对鹰蛾和蜜蜂的视觉系统都很明显。
结论:感觉刺激的内部模式表明,天蛾对棘刺梭菌有很强的历史选择。我们的研究揭示了两个有趣的悖论:(a)表型上偏向于更不一致的传粉媒介的花朵;(b)花卉展示需要丰富的资源,这些资源似乎在刺槐的栖息地中适应不良。向适应大型蜜蜂的二元授粉系统的过渡不需要表型变化,由于特定的生态生理适应,与授粉无关,这使得这种植物在授粉生态学中是一个不寻常的例子。
Capparis spinosa is a widespread charismatic plant, in which the nocturnal floral habit contrasts with the high visitation by diurnal bees and the pronounced scarcity of
hawkmoths. To resolve this discrepancy and elucidate floral evolution of C. spinosa, we analyzed the intrafloral patterns of visual and olfactory cues in relation to the known sensory biases of the different visitor guilds (bees, butterflies, and
hawkmoths).
We measured the intrafloral variation of scent, reflectance spectra, and colorimetric properties according to three guilds of known visitors of C. spinosa. Additionally, we sampled visitation rates using a motion-activated camera.
Carpenter bees visited the flowers eight times more frequently than nocturnal
hawkmoths, at dusk and in the following morning. Yet, the floral headspace of C. spinosa contained a typical sphingophilous scent with high emission rates of certain monoterpenes and amino-acid derived compounds. Visual cues included a special case of multisensory nectar guide and color patterns conspicuous to the visual systems of both
hawkmoths and bees.
The intrafloral patterns of sensory stimuli suggest that
hawkmoths have exerted strong historical selection on C. spinosa. Our study revealed two interesting paradoxes: (a) the flowers phenotypically biased towards the more inconsistent pollinator; and (b) floral display demands an abundance of resources that seems maladaptive in the habitats of C. spinosa. The transition to a binary pollination system accommodating large bees has not required phenotypic changes, owing to specific eco-physiological adaptations, unrelated to pollination, which make this plant an unusual case in pollination ecology.