Corals are pretty and colorful and fluorescent. They produce their vibrant colors because they don't live alone, which is also what keeps them alive.
Over billions of years they've worked out a special arrangement with algae: Corals give them shelter and algae convert light into food for the corals. Corals do other things for the algae, too. Deep inside their tissue are little proteins that take the sun's ultraviolet light and turn it into a glowing green sunscreen, shielding from the sun these corals that live just below the water's surface.
But deeper in the water, it's dark and the little light that reaches that far down is only in the blue part of the spectrum. Somehow, there are corals that live up to hundreds of feet below the surface and also manage to glow burning hues of orange and red.
The reasons for this fluorescence have remained a mystery, until now: These deep-sea corals glow to get more sunlight, according to a study published July 5 in the journal Proceedings of the Royal Society B. Their proteins soak up the scarce light and shine it back out as red-orange light that penetrates deep inside their tissues where their microscopic roommates take up residence. This means there's light for photosynthesis, and the algae creates energy and food for the coral.
Joanna Klein, New York Times
Shorter and arthritic, but survived an ice age
As early humans migrated into colder northern climates, a genetic mutation that knocks about a centimeter off height and increases the risk of osteoarthritis by up to 80 percent may have helped some of them survive the most recent ice age.
While some traits resulting from this mutation may seem unfavorable today, they were advantageous to early humans venturing out of Africa about 60,000 years ago.
"There are many cases like this where evolution is a trade-off," said David Kingsley, an author of the study, which appeared in Nature Genetics on July 3, and a professor of developmental biology at Stanford University.
The shorter stature may have helped these prehistoric humans retain heat and stave off frostbite in their extremities, the authors said. It also may have reduced their risk of life-threatening bone fractures when slipping on icy surfaces. But the same gene puts humans at greater risk for arthritis in the modern era as they live well beyond their reproductive years.
Aneri Pattani, New York Times
How to attach a video camera to a whale
This is how you put a video camera on a whale. Hop into an inflatable boat and head out to where they're feeding. Stand in a pulpit with a 20-some-foot pole in your hands. Then watch and wait until you spot a whale. Plan your angle of approach with the driver of the boat. (Never approach directly from behind). Get close. Get closer. Get within 16 feet of this sea giant — which is more than twice the size of your boat if it's a humpback — and as soon as it surfaces, tap the whale on its wet tire of a back with the pole. If you're lucky, the detachable suction-cup on the end of the pole — which has a camera and sensors — will stick.
"You've just put an instrument on the biggest animal that's ever lived, and you got the most incredible view while doing it," said Ari Friedlaender, a marine ecologist at Oregon State University who says he has become so proficient at tagging whales that he doesn't even notice the boat rocking. "Afterwards there's kind of an adrenaline rush."
When tagging snoozing humpbacks in the Antarctic, Friedlaender said he turns off the boat's engine and paddles up quietly, speaking only in whispers so he doesn't wake the whale. But then the suction cup hits with a loud slap and — nothing happens, usually, much to his surprise.
This doesn't always work out. One time a whale woke up, got curious and played with the boat, swimming under it and rolling along it. The camera captured the encounter. "We were hoping we got a look of what it's like for a whale to live in the Antarctic, but we got an hour of it looking at us," he said.
Joanna Klein, New York Times
Forget robots — the goats are coming for our jobs
A Michigan chapter of the American Federation of State, County and Municipal Employees is warning that somebody is coming to take union jobs. Not immigrants, not robots — but goats. After Western Michigan University rented a crew of 20 goats to clear weeds and brush this summer, AFSCME "filed a grievance contending that the work the goats are doing in a wooded lot is taking away jobs from laid-off union workers," according to the Detroit Free Press.
With their voracious appetites goats can clear weeds and brush in areas that humans have a hard time reaching. They're gentler on the environment than heavy landscaping equipment or chemicals. They will eat literally anything, including poison ivy.
If you're a union representing guys who mow or clear brush for a living, you can see the threat coming from a mile away — even if said threat has two horns, four legs and looks adorable in a sweater.
AFSCME's warning got us thinking — just how many jobs are really at risk from the rise of goat-scaping? We did a heavily simplified, back-of-the-envelope estimate of the potential impact of goat labor on the U.S. workforce: In a month, our typical human can do the brush-clearing work of about 3,600 goats. Take that, goats! Humans rule!
Christopher Ingraham, Washington Post