A Plant That Can Smell
BlueCup writes "The question of how a dodder finds a host plant has puzzled researchers. Many thought it simply grew in a random direction, with discovery of a plant to attack being a chance encounter. But the researchers led by Consuelo M. De Moraes found that if they placed tomato plants near a germinating dodder, the parasite headed for the tomato 80 percent of the time. And when they put scent chemicals from a tomato on rubber, 73 percent of the dodder seedlings headed that way. Turns out, it sniffs out it's prey."
Smell isn't anything more than detecting fairly dilute chemicals
in the air. The fact that some species of plant have evolved to
perform very specific kinds of chemical detection to ensure their
survival doesn't seem surprising to me. Plants grow towards the
light - why not towards other things that are essential for their
survival.