Discovered: Elephants communicate through "infrasound"; allergies may help prevent brain cancer; playfulness is attractive; 97% of Greenland's surface ice is melting.

Greenland, a real life Waterworld? How's this for a chill-inducing statistic about global warming? About 97 percent of Greenland's surface ice has melted temporarily, a result of what might be the biggest heat wave in a century. Even the highest, chilliest point in Greenland has shown signs of melting. Marco Tedesco, City University of New York professor, recently predicted that a major thaw would happen within the next decade. Little did he know it would come this soon. "Nature could have caused this [year’s] melt event by chance," Penn State glaciologist Richard Alley admits. "But humans made it more likely with greenhouse gases." [Science News]

Don't hate the player. For most species in the animal kingdom, adulthood corresponds with the end of play. But thanks to sports and other physical activities, most of us humans don't stop playing upon reaching adulthood. Researchers at Penn State think they know why. Human adults may use playfulness as a way to attract mating partners. "Birds display bright plumage or coloration," notes professor Garry Chick. "In the same vein, playfulness in a male may signal to females that he is nonaggressive and less likely to harm them or their offspring. A woman's playfulness, on the other hand, may signal her youth and fertility." The researchers reached this conclusion by administering a survey about characteristics that people seek in prospective mates, including "playful" as one of the 16 possible traits. Female respondents reported that it was the fourth most important trait, on average, that they sought in males. [Penn State]

Elephants do talk, we just can't hear them. New research on elephants shows how the giant creatures communicate with each other through "infrasounds," sounds so low in pitch that humans can't detect them. It was previously hypothesized that elephants made these sounds by relaxing the larynx, in much that same way that cats produce a purring sound. But University of Vienna researchers have discovered that elephants use the organ in the same way that we humans do when speaking or singing. Like us, elephants vibrate their vocal chords to produce sound, but do so much more slowly and through much longer vocal folds. The researchers reached this conclusion by blowing air through the removed larynx of an elephant that had died of natural causes. [University of Vienna]

Be thankful for your allergies. When springtime has you all stuffy and watery-eyed, it's hard to find any reason to be grateful for your allergies. But new research from Ohio State University might change your mind. Judith Schwartzbaum, OSU associate professor of epidemiology, finds that people with allergies are less likely to develop glioma, a cancerous tumor that originates in the brain and spine. "It could be that in allergic people, higher levels of circulating antibodies may stimulate the immune system, and that could lower the risk of glioma," she says. The reduced risk is higher for female allergy sufferers than it is for men. [Ohio State University]