Discover September 2014

Mystery Stories This time last year, the Discover team was as busy as it has ever been. We were just putting the finishing touches on a redesign of the magazine, always a chaotic and time-consuming point in the life cycle of any publication. While we introduced many new elements with that frst new issue, quite a few old, cluttersome items departed from Discover for good. Our Vital Signs column, which invites readers to follow along with a doctor as he or she strives to solve an unusual medical case, was not one of those permanent deletions. Readers could be forgiven for thinking it was, though: Due to various editorial concerns that I won’t belabor, we had to cut two pages from the magazine at the last minute, so we pulled…

Cross Contamination Corey Powell’s May “Out There” column discussed the search for alien life. “Why is E.T. MIA?” suggests sending a probe to “simply” take a few passes through the ejecting plume of a moon of Saturn and bring back samples to Earth labs to look for alien life. What if the sample contains a pathogen that wiped out life on Saturn? Exposure to such things is a high price to pay to satisfy curiosity. Laurie Goffman Palm Desert, CA Author and editor at large Corey Powell responds: That’s a very valid concern. Fortunately, it is one that people at NASA have thought about extensively; in fact, NASA has a whole office devoted to the issue of “planetary protection” from contamination. The office establishes rules both to make sure we…

The Stories Behind the Latest Science News FRACTAL FANTASY They’re simple in concept, yet beautifully complex. And nature is full of them — unending geometrical patterns called fractals that, regardless of scale, look the same. Jos Leys, a retired engineer from Antwerp, Belgium, created this 3-D fractal scene using his own formulas and Ultra Fractal, a fractal-generating program. “I am always on the lookout for mathematical theories that can produce images that no one has ever seen,” he says. Creating a scene with these fractal images is a game of trial and error, with slightly different initial conditions producing entirely different images. — ERNIE MASTROIANNI, IMAGE BY JOS LEYS…

The world’s reef systems face unprecedented stresses, under threat from over fishing, pollution and climate change. Most threatened is the Caribbean reef system, with more than 80 percent of its live coral cover disappearing since the 1970s, largely due to global warming. A visual example of this toll is called coral bleaching, which turns the animals a ghostly white — the result of warmer waters expelling the algae that give coral its color and sustenance. An innovative project in southern Belize is working to turn the tide not just by rebuilding reef systems, but also by learning from natural heat-resistant corals. The research was inspired by a serendipitous discovery after Hurricane Iris tore through Central America in 2001. The storm demolished large swaths of the Belize Barrier Reef system, part…

Jason Drew’s farm doesn’t include artisanal arugula or free-range livestock. His South African company, AgriProtein, grows flies. The pests have the same amino acids as more expensive commercial fish meal, making them an attractive protein source for poultry and fish farmers. After the fly eggs hatch, the larvae feast on waste: leftovers from human food production like juice pulp, and slaughterhouse scraps like pork blood. Some of the larvae are then harvested, dried and pressed into different shapes as food for various seafood and poultry species. The larvae that escaped the food mill grow up and continue the cycle, laying eggs. Two new factories in South Africa will each soon house 8.5 million flies, and have a daily output of 30 tons of pressed larvae — fly farming on an…

It’s an oddity of physiology Humans can’t tickle themselves. Studies suggest this stems from the brain’s ability to predict sensations caused by our own movements, removing the surprise necessary for a good tickle. But George Van Doorn, a psychologist at Federation University in Australia, wanted to find out if the brain’s predictive power really explains why we can’t tickle ourselves. It’s a serious question, since tickling gives us a clue as to how the brain processes sensations, and can even teach us a bit about mental illness. (People with schizophrenia, for instance, actually can tickle themselves, for unknown reasons.) “The dominant theory also suggests that in highly surprising situations, a person will be able to tickle themselves,” Van Doorn says. The brain’s predictive abilities become too poor. To simulate this…