No. 115: Jan-Feb 1998
In Costa Rica, the plant Macuna holtoni, a vine-like member of the pea family, is pollinated by bats. To help echolocating bats to find its flowers in the dark, it has evolved a single petal on each blossom that is shaped like a concave ultrasound mirror. A bat searching for nectar- and pollen-bearing flowers with its ultrasonic cries can zero in on the strong echoes reflected from the plant. Both plant and bat benefit.
(Anonymous; "Bat Mirror," New Scientist, p. 29, November 8, 1997.)
Comment. What a neat, technically sophisticated adaptation. How did this plant "know" that the bats echolocated ultrasonically and what a good reflector would look like? Don't worry about trivia like this, evolution can explain everything!