Pellmyr Olle
Dept of Entomology, Uppsala University, Box 561, S-751 22, Uppsala, Sweden.
Oecologia. 1986 Jan;68(2):304-307. doi: 10.1007/BF00384804.
Cimicifuga simplex, a Japanese herb, has three different pollinator guilds. At high altitudes it is pollinated by bumblebees. In lowlands, Impatiens textori, a much superior nectar-producer, outcompetes it for bumblebees. In sunny lowland habitats, flowers of a second morph produce a two-component fragrance which facilitates pollination by fritillaries. In experiments, the two components separately had limited effect on alighting rate, while application of both together elevated the attractiveness of non-fragrant flowers to the same as for naturally fragrant flowers. In heavily shaded lowland habitats, a third morph with nonfragrant flowers does not blom until after I. textori, and is pollinated by occasional bumblebees. The data strongly suggest that inferiority in competition has induced incipient speciation in this plant species.
单穗升麻，一种日本草本植物，有三种不同的传粉者群体。在高海拔地区，它由大黄蜂授粉。在低地，产蜜量高得多的东北凤仙花在争夺大黄蜂方面比它更具优势。在阳光充足的低地栖息地，第二种形态的花朵产生一种双组分香味，便于贝母进行授粉。在实验中，这两种成分单独使用时对降落率的影响有限，而两者一起使用时，可使无香味花朵的吸引力提高到与天然有香味花朵相同的水平。在重度遮荫的低地栖息地，第三种形态的无香花直到东北凤仙花开过后才开花，并由偶尔出现的大黄蜂授粉。数据有力地表明，竞争劣势已在该植物物种中引发了初始物种形成。
