A Smelly Misshapen Phallus Rises in Queensland

Another stinky, giant misshapen penis plant has thrust itself into the news, this time at a botanical garden in Cairns, Australia.  Yawn. These public events are becoming a little too . . . common. I’m looking forward to the first stalk-raising of Amorphophallus titanum to take place at an exclusive VIP venue—like the Playboy Mansion. The word would spread via Hollywood publicists and soon you’d have Charlie Sheen, Kanye West, David Hasselhoff, and Ron Jeremy posing in front of an enormous, smelly botanical phallus along with all manner of babelicious young things. Now that’s a photo opp. The piece in The Courier-Mail pretty much writes itself, with one exception:

Amorphophallus titanum, which means huge deformed penis, was dubbed titan arum by Sir David Attenborough in 2008. The BBC broadcaster did not wish to refer to a giant phallic flower on his family show.

How quaintly Victorian of Sir David. He sounds like the kind of guy who serves his dinner guests “chicken chests.” In fairness, titan arum is a legit informal name for this species; it’s other nom de jardin—“corpse flower”—is strictly of recent PR vintage. For some reason this reminds me of a fund-raising dinner I attended some years ago for the Sense of Smell Institute. I was seated across the table from one of the Big Name guests, the “sex expert” Dr. Ruth Westheimer. She sat with a blank expression, waiting for a chance to work the word “penis” into the conversation. Whenever she succeeded, she would stop and grin as if expecting applause. It was jarring the first three or four times she did it, then simply annoying. It was like having dinner with someone’s senile, foul-mouthed grandmother. Blecch. Speaking of wrinkly and disgusting, I know FirstNerve readers are dying to know the exact molecular composition of the insect-attracting rotten meat smell that wafts from the Giant Penis Plant. Well, the wait is over. Last July, Mika Shirasu and colleagues studied the hell out of a blooming A. titanum at the University of Tokyo’s Botanical Gardens. They have provided the most precise olfactive description I’ve ever read of it. 

At the beginning of flowering, a faint rotten fruit-like odor was detected occasionally. Then the odor emitted from the flower gradually intensified. During full opening of the spathe, a strong rotting animal-like odor was emitted constantly. . . . The odor became stronger with heat production from the spadix . . . After the peak of the spadix temperature, the inflorescence began to secrete a fluid from the spadix in which a rotten fish-like odor was sensed.

Truly an evolving tone poem of malodor. Shirasu’s team captured the volatile emissions and ran them through a GC-MS-O analysis. The rotten animal smell was due to dimethyl trisulfide. Dimethyl disulfide was also found, but not at a concentration that was perceptible to the nose. There were also stinky grace notes of methyl thiolacetate and isovaleric acid. Finally, the rotting fish odor of the secreted fluid was due to trimethylamine. None of the molecules is exotic—they are found in everything from cheese to cooked cabbage and stinky feet. What is impressive is that this entire collection of foulness is produced by a single plant over the course of a couple of days.