Fill In the Blanks

Most people assume, correctly, that flowers look the way they do to attract insects that pollinate them. But that’s not the whole story. Scientists have now discovered that plants have another “trick up their leaves” to make themselves irresistible to even the most choosy insect solar power. Cambridge University’s Beverley Glover and her colleagues recently set up some fake flowers filled with a sugar solution, which they kept at different temperatures. Unleashing a team of bumblebees on their floral offerings , they watched as the insects visited the flowers to drink the surrogate nectar. Very quickly, it became obvious that the bees were concentrating on the flowers with the warmest nectar. Just in case it was something to do with the color of the fake flowers, the scientists also tried a different color combination and got the same result .