I’ve spent much of this week learning how plants and animals communicate using chemicals, for another prospective story. I realized there was a common purpose for most of this chemical communication: reproduction. I like calling these chemicals the sexy scents. Many plants and animals use them to advertise their virility. Pheremones croon “Mate with me!” and floral aromas call out “Pollinate me!”.
But why scents? If you smelled the waxy goo coming out of a monkey’s chest gland I’m pretty sure copulation would be the last thing on your mind. And are we really supposed to believe that tiny pollinating insects fancy themselves perfume connoisseurs?
Scientists are finding that a plant or animal’s scent can carry a Sunday’s paper worth of advertising material for prospective mates or pollinators (“I know where the good food is baby, hmm, hmm” or “My pollen is the very sweetest!”). Also, communicating through chemicals can save energy and lead to more successful reproduction. Indulge me here as I cue Marvin Gaye’s “Let’s Get it On”.
To research this story I talked with Robert Raguso of Cornell University. He studies chemical communication between flowering plants and their pollinators. Raguso tells me of how cleverly plants use scent to lure and even trick pollinators. Communicating with chemicals allows plants to send pollinators complex messages. The scents they emit are ofter composed of hundreds of different chemical compounds. Scents can also attract pollinators with poor eyesight or those that fly at night. Some species of tropical orchids use scent to trick males bees into thinking the flowers are female bees. The mistaken males rub up against the flower in vain, but they do succeed in pollinating the plant. Raguso says plants that advertise visually have to constantly spend energy sustaining their impressive blooms, while plants that advertise with smell can limit scent production to times when pollinators are near.
I also talked with Anthony Di Fiore of New York University. He studies primate mating behavior. He explains how some monkeys emit scent chemicals from glands on their chest or ano-genital region. These scents can boast on topics ranging from their arousal level, to their physical strength, to their access to resources. Most interestingly, Di Fiore’s found that monkeys who use chemical communication are much less aggressive towards each other than other monkeys. They don’t have to waste energy fighting for mates because their scent automatically displays their dominance.
This could be a fun piece if I could get some human actors to verbalize what these plants and animals are “saying” with chemicals. I like the idea of having little snippets of a radio drama within a more science-y story.