Smithsonian.com

A sprite, about 175-250 miles away (credit: ILAN Science Team)

This may look like a flying saucer of movie fame, but it’s really an atmospheric phenomenon called a “sprite.” Sprites appear 35 to 80 miles above the earth’s surface; they can be set off when the lightning from a thunderstorm (only 7 to 10 miles high) excites the electric field farther up in the atmosphere. Though they appear above most thunderstorms, they appear so briefly—less then a second—and so high up that it’s not so shocking that they weren’t discovered until 1989. Like other similar phenomena called “elves,” “trolls” and “goblins,” sprites dance in the sky and are thought to be the source of some UFO sightings.

An employee at the National Zoo’s commissary prepares meals for residents at the Great Ape House.

Six-o-clock in the morning is when the action begins at the National Zoo. Think you’re grumpy without breakfast? Just imagine how Mei Xiang and Tian Tian, two of the Zoo’s giant pandas, would feel without their bamboo.

Yesterday morning, I joined a zoo employee in a truck marked, “The Bamboo Never Stops,” as he delivered approximately 250 stalks of the treasured plant to the pandas, apes, elephants and several other species that enjoy the low protein, high fiber content of the leaves and stalks.

When we returned, it was off to the kitchen. With the radio softly playing in the background, we watched as nutritionists mixed bananas, lettuce, apples, carrots and corn with dozens of animal-specific biscuits. They weren’t the warm and toasty buttermilk biscuits you may enjoy for breakfast, but chicken-nugget sized combinations of oats and grains lightly flavored with citrus.

Every animal has a personalized diet, designed by a team of zoo nutritionists. The diets account for personal tastes, whether the animal runs around a lot or remains stationary, as well as age and health. For example, one gorilla received a biscuit and greens along with a beet, onion, cucumber, melon and banana.

If you ever host a dinner party for the following zoo animals, here’s what you need to know:

For penguins: These flightless birds have a taste for seafood. They’d be happy with a variety of fish, krill or squid. And no need for silverware! It’s recommended that penguins be hand-fed.

For fruit bats: Don’t let their name deceive you. These guys are picky eaters. Depending on the crowd, you may be forced to serve fruit, nectar, pollen, insects, blood, small mammals, birds, lizards, frogs or fish. It’s best to make this one a pot luck.

For Asian small-clawed otters: You may be better off going to a steak house if you have these furry guys over. Minced beef, fish, hard-boiled eggs, and locally available shellfish and crabs should be provided. Though they may not mind a bit of dog or cat food.

Wondering what your local lion or zebra is eating? You can find more nutrition advice at the American Zoo Association Web site.

– Joseph Caputo

What’s your take on this? Dorky? Effective?

(Hat tip to the Knight Science Journalism Tracker)

Science can turn you into a full-time skeptic (as my friends discover at some of the oddest times), but that’s not a bad thing. I’m sure that Smithsonian’s favorite skeptic, James Randi, has had plenty of cocktail conversations in which people try to convince him that they found the magic cure to all his ills, or some other form of woo. But then, he solicits this sort of thing—the James Randi Educational Foundation offers $1 million “to anyone who can show, under proper observing conditions, evidence of any paranormal, supernatural, or occult power or event.”

As the foundation notes: “To date, no one has passed the preliminary tests.”

In this video from the Amazing Randi, we can get a hint of the kind of person who applies for the $1-million-prize. This time it’s a dowser. Watch the video to learn how dowsing really “works.”

Maybe the guy should have watched the next video before submitting his claim. In it, a group of dowsers in the United Kingdom are subjected to a double-blind test of their dowsing ability. Will anyone pass the test?

(Hat tip to Bad Astronomy)

A meerkat at Taronga Zoo, Sydney

Those adorable little meerkats aren’t just good TV fodder—they’re great research fodder as well.

A couple of University of Zurich scientists, publishing in the March issue of the American Naturalist, studied alarm calls produced by meerkats and Cape ground squirrels that lived sympatrically on the Kalahari Desert.

Alarm calls produced by animals come in two flavors: One type denotes only a level of urgency, while the other includes information about predator type and how individuals should respond (“functionally referential” signals). Theories of how these alarm calls evolve have suggested that the type of alarm call used by a species is influenced most by how it responds to threats. Species that use different strategies for escaping different predators, logically enough, would be best served by functionally referential signals. But creatures that use a single strategy would need only the urgency level in their alarms.

The meerkats and Cape ground squirrels, though, respond in a similar fashion to threats—they run for cover, escaping down bolt holes into burrows that the two species often share. The Cape ground squirrels use the urgency-dependent alarm calls, as would be expected by the theory, but the meerkats use functionally referential signals. Why the difference?

The Cape ground squirrels eat vegetable matter that they can find close to home, while the meerkats have to venture farther for their meals of insects and other small animals. The Cape ground squirrels don’t lose much by retreating to their burrows, because they aren’t that far away. The meerkats, though, can’t run home every time they’re threatened, because the cost would be too high (lost yummies). They respond differently to different threats (such as by moving away from an ambush predator like a jackal instead of returning all the way to the burrow and trying to wait the jackal out). In addition, the meerkats have to be able to respond in the same way to a threat, because if one runs in the opposite direction of the group, he could be toast (single meerkats and small groups have a higher likelihood of being eaten by a predator).

This video (meerkats responding to the “threat” of an ultralight plane flying above) comes from YouTube user nyatnagarl who has made many videos of the meerkats at the Hanover Zoo in Germany and has noticed:

The meerkat group react[s] quite differently to the aerial encounters made in this location:

* Passenger jet planes high in the sky – usually ignored, but at sunset, when they are caught and illuminated in the sky by the last rays of the sun, they are watched closely, but an alarm is never raised.

* Small propeller planes (Cessna, etc.), low flying – sometimes completely ignored (i.e., not even the head is raised), sometimes watched. Since there is a small airport nearby, they know these planes very well, and understand they pose no danger. In general the sound of the classic piston engine aircraft is associated with “not dangerous”, you can often hear an engine drone in parts of the videos I have posted.

* Anything that has a triangular shape like hang gliders, ultralights – will usually cause an intense warning. It is worse when the flying object is silent (like hang gliders) – this will usually cause an at least partial retreat of the family into the burrow. A silent slowly moving object with swept wings probably reminds them most of a predatory bird.

* Hot air balloons – they do not like these at all. Although they are usually distant, the silent, looming presence on the horizon seems to disturb the meerkats deeply. They will usually watch these intently and most activity will cease until they disappear.

* Zeppelins – we don’t get these very frequently but when the “Zeppelin NT” flew over the enclosure at low altitude one afternoon it was considered the ultimate enemy. The meerkats raised alarm, disappeared into the burrow and did not reappear for the rest of the day!

Back in the day, when I was studying ecology as an undergrad, I learned about the giant kelp forests off the coast of California because they are home to a keystone species, the ever adorable sea otter. The sea otters like to feast on sea urchins. But when there aren’t enough of the cute little marine mammals, the sea urchins run rampant, feasting on the giant kelp. Unchecked, the sea urchins can destroy an entire forest.

Why is that bad? The Monterey Bay Aquarium explains the importance of the giant kelp:

Giant kelp is harvested as a source of algin, an emulsifying and binding agent used in the production of many foods and cosmetics, like ice cream, toothpaste and cereals.

Pieces of decomposing kelp (detritus) sink to the depths of the ocean, providing food for deep sea creatures.

Giant kelp has a multitude of inhabitants. Invertebrates graze on the blades, fish seek shelter in the fronds and thousands of invertebrates live in the holdfast—such as brittle stars, sea stars, anemones, sponges and tunicates.

The National Marine Sanctuaries program has created an online media library with plenty of photos of kelp and other marine treasures, such as sea lions, as well as some truly devastating pictures of the human impacts on the oceans.

Credit: Steve Lonhart / Monterey Bay National Marine Sanctuary

One of the big themes of this year’s AAAS meeting was—you guessed it— Charles Darwin. It seemed like every session’s chairperson was obliged to mention Darwin’s 200th birthday, and some scientists even sounded like they were channeling him at a seance.

Scientists have been talking about Darwin’s finches and orchids and barnacles for a solid 150 years now, but the focus this year was on Darwin’s humans. Specifically, why humans are emotional, social and even moral beings. Here’s Darwin on the origins of human communities, in The Descent of Man:

It has often been assumed that animals were in the first place rendered social, and that they feel as a consequence uncomfortable when separated from each other, and comfortable whilst together; but it is a more probable view that these sensations were first developed, in order that those animals which would profit by living in society, should be induced to live together. …For with those animals which were benefited by living in close association, the individuals which took the greatest pleasure in society would best escape various dangers; whilst those that cared least for their comrades and lived solitary would perish in greater numbers.

At the conference, there were presentations on “The Evolution of Emotion and Emotional Expressions in Humans and Other Primates,” “The Evolution of Human Social Cognition,” “The Origins of Complex Societies in Primates and Humans,” and many others along this line. As Barbara King of the College of William and Mary pointed out, people study great apes and other primates to get clues about how our shared ancestors behaved to each other, and even what emotions they felt. “We wouldn’t be humans if ancient apes hadn’t been deeply emotional and social,” she says.

All evolutionary theorizing aside, the best part about attending these types of talks is that you get to see fun film clips of chimps or gorillas or orangutans playing or fighting with one another—basically, apes going ape. This one is from King’s work at the National Zoo. Here’s how she describes it:

When a conflict breaks out between a silverback and a blackback male, the family members (not biological but social family members) literally line up in support of the younger male. The juvenile male…even tries to intervene, only to be swatted away effortlessly. We see emotion here: not just on the screaming nervous face of the blackback (I should add, the defecating and screaming blackback) [Ed. note: you're not having computer problems; the video has no audio], who shows his fear even as he refuses to do what the silverback wants him to do—but also in the ways that the social bonds become visible to us in the apes’ actions.

Enjoy!

Since I was in Chicago this past weekend (Laura and I attended the AAAS annual meeting—we wrote about fembots, the 1000th Steve, origami, and award-winning science journalism), I took the opportunity to go up to the top of the Sears Tower. As I gazed out over the city, looking down on the roofs of buildings hundreds of feet below, all I could think about was the expanse of unused space—acres of square footage (rooftops) that could be filled with solar panels and greenery.

The view from the Sears Tower, facing south (courtesy of Flickr user allenwatch)

It turns out that I am, thankfully, not the first person to have had these thoughts about the Windy City. The Chicago Green Roof and Cool Roof Grants Program has been handing out funds for creating green roofs since 2005.

Green roofs have several benefits:

• Clean and retain rainwater
• Reduce ‘Urban Heat Island Effect’ (overheating of cities in summer which contributes to pollution and increased energy consumption)
• Add beauty to our urban landscape
• Help lower air temperatures
• Improve air quality for everyone
• Lower heating and cooling bills
• Extend the life of the roof membrane (2 to 3 times!)

Chicago should be commended for their environmental efforts (the city’s Department of Environment Web site has information on other projects, such as Chicago Green Homes), but I could see from the Sears Tower that they still have a long way to go.