DARK ATTRACTION

Girl frog comes on to guy with red sac. CREDIT: MARY THERY AND DORIS GOMEZ

The sight of a pulsating vocal sac can excite a frog. To see if color could also be a turn-on, scientists at the Muséum National d'Histoire Naturelle in Paris exposed 70 female frogs to two computer screens displaying images of a male, adjusted to appear as he would at night. Speakers alternately played identical male calls; the only difference was that on one screen the male had a dark red vocal sac and on the other, a pale brown one. If a female lingered for 30 seconds in a "choice area" near either image, she was assumed to be signifying a desired mate.

Females were overwhelmingly drawn to the image of a frog with a darker, more colorful sac. Some climbed onto the screen to solicit the virtual frog. So even when lights are low, sac coloration may signal a quality mate, says evolutionary biologist Marc Théry, co-author of a paper online 25 March in Biological Sciences.

"This is a fascinating paper," says ecology graduate student Victoria Arch of the University of California, Los Angeles. It shows "the importance of considering multimodal cues" in mating, even in nocturnal species.

... so fellas, if you're having trouble with the ladies in the clubs, you might want to try out your new red sac...

The other day I was missing being single.  "Life now is just too methodical!" I thought to myself, "Why can't we just eat yogurt with granola for dinner every once in a while?  Why does everything have to be so freaking planned?  Why can't I just eat some edamame and sit on the couch watching crap TV for the rest of the night?!?  Why do we have to do dishes and laundry and be so freaking responsible all the time?!?"  And then I remembered all the reasons why being single was so lonely, and then I told myself to shut up.