Saturday, January 29, 2011

Seahorse Shape Explained as Stealth-Attack Adaptation

According to a new explanation of seahorse shape, those distinctive S-curve bodies let them reach further than straight-bodied ancestors.

Compared to tube-shaped pipefish, their closest relatives, seahorses extend their snouts an extra 30 percent. The difference is only a few millimeters, but for animals with a strike range of a centimeter or two, it’s a big advantage.

“This makes them stealthier and sneakier hunters,” said Lara Ferry, an Arizona State University ecomorphologist who co-authored the study, published Jan. 25 in Nature Communications. “Their prey is less likely to spot them coming, and they are less likely to miss a meal.”

To test the link between shape and hunting ability, Ferry’s team created a computer model predicting the movements of seahorses and pipefish. By tweaking the features of the model fish, they could estimate how body curvature affected range. They verified their results with high-speed video of seahorses and pipefish feeding.

The videos were needed, Ferry said, because the naked eye can’t see seahorses feed. They’re among the fastest eaters known.

“From the time they spot prey and open their mouth, to the time the shrimp is completely devoured, is only four milliseconds,” said Ferry.

Seahorses rely on stealth attack because they’re poor swimmers. While most fish, pipefish included, swim towards their prey, seahorses hide in sea grasses or corals, hang on with a prehensile tail, and wait for tiny shrimp to float by. To prepare for a strike, they tense their muscles and — like a stretched sling-shot — snap forward. (Watch video from Nature’s website.)

Seahorses are also unusual for being monogamous, and are among the only species in which males bear young.

(Read the original post and see more seahorse photos on 

Monday, January 24, 2011

Why canned beer is better: This day in history

My piece on This Day in Tech, from

Jan. 24, 1935: First Canned Beer Sold

1935: The first canned beer in the United States goes on sale in Richmond, Virginia. By the end of the year, 37 breweries follow the lead of the Gottfried Krueger Brewery.

The American Can Co. began experimenting with canned beer in 1909. But the cans couldn’t withstand the pressure from carbonation — up to 80 pounds per square inch — and exploded. Just before the end of the Prohibition in 1933, the company developed a “keg-lining” technique, coating the inside of the can the same as a keg.

Krueger had been brewing beer since the mid-1800s, but had suffered from the Prohibition and worker strikes. When American Can approached with the idea of canned beer, it was initially unpopular with Krueger execs. But American Can offered to install the equipment for free: If the beer flopped, Krueger wouldn’t have to pay.

So, in 1935 Krueger’s Cream Ale and Krueger’s Finest Beer were the first beers sold to the public in cans. Canned beer was an immediate success. The public loved it, giving it a 91 percent approval rating.

Compared to glass, the cans were lightweight, cheap, and easy to stack and ship. Unlike bottles, you didn’t have to pay a deposit and then return the cans for a refund. By summer Krueger was buying 180,000 cans a day from American Can, and other breweries decided to follow.

The first cans were flat-topped and made of heavy-gauge steel. To open, a hole had to be punched in the top with the sharp end of a church-key style opener.

Some breweries tried out cans with conical rather than flat tops, but they didn’t stack and ship as easily. Cone tops were sealed with a crown cap just like the cap of a glass beer bottle.

Canning was interrupted between 1942 and 1947 to devote resources to World War II. Aluminum cans, cheaper and lighter still, were introduced in 1958.

Beyond their economy and convenience, cans are actually better for beer than glass bottles. This isn’t the heresy it sounds. Beer’s main enemies are light, oxygen and heat. A can’s complete opacity blocks out the light that can make a beer taste “skunked.”

Beer becomes skunked or “light-struck” when light splits its riboflavin, a type of B vitamin. The ruptured riboflavin can react with isohumulones, chemicals that come from hops and help beer taste bitter. The resulting molecule is similar in shape and smell to the musk sprayed by skunks. That’s why most microbreweries sell beer in dark brown bottles or, increasingly, in beer cans.

Source: various
Image: C-Monster/Flickr

Saturday, January 22, 2011

Gallery on Wired Science: 8 Beautiful Bioluminescent Creatures From the Sea

Atolla, a deep sea jelly fish. Image Steve Haddock, MBARI.

While a handful of land animals can create their own light, homemade luminescence is the rule rather than the exception in the open ocean's dark waters.

Researchers estimate that between 80 and 90 percent of deep-dwelling animals are bioluminous, creating light by mixing the pigment luciferin with luciferase, the enzyme that makes it glow. The light tends to green and blue, colors that travel far in seawater. Glowing helps attract mates, lure prey or confound predators.

Many of these animals live thousands of meters deep and are difficult for scientists to find and study. Here are some of the prettiest — and strangest — glowing creatures of the seas.

Check out the rest at Wired Science.

Saturday, January 8, 2011

First day at I survived

All a twitter with excitement, I lived through my first day at, in spite of the jitters. What for me was a momentous day, was routine for everyone there. Interns, I gather, cycle pretty regularly through the offices -- we're a cheap and eager source of labor. But for us, it's a step in the direction of our aspirations. It doesn't matter that we're a dime a dozen. It is *our* dime that is in the pot of change.

To my editor's credit, she gave me an easy assignment and a early deadline immediately. So, prior to lunch on my first day, I already had my first bylined piece on the site. Read it here or see it below!

The Earth-orbiting satellite Hinode caught this stunning video of the annular solar eclipse Jan. 4.

An annular eclipse occurs when the moon is slightly farther from Earth than usual and appears slightly smaller. When it moves between the Earth and sun, it covers the center of the sun, leaving a bright, fiery ring, or annulus, at the edge.

Hinode, a Japanese mission, studies the sun’s magnetic fields and surface eruptions. The satellite carries three NASA-developed telescopes that capture different types of light:
  • The optical telescope sees visible light.
  • The X-ray telescope, which took the video above, can see deep inside the corona.
  • The ultraviolet-light telescope reveals the deep, high-temperature processes that heat the sun’s corona.
This will be a good year for eclipse fans. With four partial-solar and two total-lunar eclipses upcoming, watch for more sun shots.
Video: Hinode/XRT

Happily, I'll be living in San Francisco for the weekends for a little while, at least for this month. I adore this city. I'm working in a cafe called "Nervous Dog Coffee" (doggy treats in a jar by the door), munching on an outrageously delicious Mediterranean turnover, CoCo Rosie is playing on the sound system, and the name of the woman's dog next to me is "Chomsky." It's a quintessential SF moment.