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Golden jellyfish in Palau's Jellyfish Lake (credit: Michael Dawson, University of California at Merced)

Most of the organisms living in the oceans are tiny, but they have a big effect on ocean mixing, according to a new study in Nature. Bioengineers from CalTech investigated this effect in Palau by adding a fluorescent dye to water near jellyfish to see what would happen when the jellies swam through. To the scientists’ surprise, the dye traveled along with the jellyfish for long distances. Jellyfish and other marine organisms regularly migrate to the ocean surface during the day. Extrapolating from their experiment, the bioengineers calculated that the amount of mixing from this migration is as much as a trillion watts of energy, about equivalent to the effects of the winds and tides.

It turns out there’s more to a toucan’s bill than pretty colors and a penchant for Fruit Loops.

The beak of the toco toucan acts as a thermal regulator. Image courtesy of Flickr user rougenair.

Originally described as “grossly monstrous” by the Comte de Buffon, the toucan’s beak was theorized by Charles Darwin to be related to sexual selection. The toucans with the biggest bills were thought to have the most success attracting a mate and reproducing, the same explanation used for the extravagant plumes on peacocks.

However, scientists now have evidence that the long beak of a toucan regulates heat distribution, acting as a thermal radiator of sorts. Glenn J. Tattersall of Brock University and Denis V. Andrade and Augusto S. Abe of Sao Paulo State University studied the toco toucan (Ramphastos toco), the largest member of the toucan family that also has the largest bill relative to body size of any bird.

Using infrared thermography and thermal imaging cameras, the team monitored the toucans’ response in a temperature-controlled chamber. Below a temperature of about 60 degrees Fahrenheit, the beak was somewhat colder than ambient temperature, meaning that the blood vessels between the bony core of the bill and its hornlike covering were constricted.

Conversely, as temperatures increased above 70 degrees, blood flow increased, making the bill warmer and helping the bird cope with the extra heat load.

In a recent paper published in Science researchers note:

Our results indicate that the toucan’s bills is, relative to its size, one of the largest thermal windows in the animal kingdom, rivaling elephants’ ears in its ability to radiate body heat … Given the rapid radiation of bill structures and diversity of beak morphologies of birds, thermal constraints from bill heat loss may prove to be a common feature among many avian fauna.

Earlier this year, I read Flotsametrics and the Floating World, by Curtis Ebbesmeyer and Eric Scigliano, about ocean currents, how they have influenced history, and human impacts on the vast seas. (We published an excerpt, “Borne on a Black Current,” earlier this year.)

Ebbesmeyer, an oceanographer, is perhaps best known for his work tracking bath toys and sneakers to map the ocean’s flow. But it was the chapters in which he and Scigliano described the acres and acres of plastic junk floating across the seas, washing up on distant shores by the ton and being consumed by wildlife, that I found most disturbing. And it’s not just the plastic that we toss away that’s the problem. Those bath toys and sneakers have come from container ships that lost their cargo. Other lost shipments are not nearly so innocent, Ebbesmeyer writes:

Greenpeace estimates that 10 percent of the 100 million tons of plastic produced each year worldwide ends up in the sea. That global production includes, by various estimates, 500 billion to 1 trillion plastic bags. It takes just one bag to choke a hungry sea turtle. If that 10 percent estimate holds for bags, then enough drift into the sea each year to kill all the sea turtles in the world thousands of times over. One shipping container holds about 5 million plastic bags, and I know of at least two such containers lost in the Turtle Gyre [in the North Pacific]. No one knows what happened to their 10 million bags. The shipping industry is proud that it’s reduced its annual loss rate from about ten thousand to two thousand containers out of roughly 100 million shipped each year. I tell them it only takes one to cause a catastrophe.

Captain Charles Moore, of the Algalita Marine Research Foundation, found the Great Pacific Garbage Patch during a 1997 yacht race. (Ebbesmeyer has tallied eight garbage patches in total: four in the Pacific, three in the Atlantic and one in the Indian Ocean.) Since then, he has worked to understand how the plastic influences marine life and to make people aware of the problem. He gave the Ted Talk above in February of this year. The pictures are gut-wrenching.

Stealing a meal from a lion, on first thought, seems like a bad idea. Lions kill people. But this might not be such a bad strategy, and it could have been one that helped early humans to obtain protein and survive. It might also be a practice that continues in Africa today, according to biologists who witnessed an episode of kleptoparasitism (stealing prey from another) in Benoue National Park in Cameroon a few years ago. Their report appears in the African Journal of Ecology.

Would you steal a lion’s dinner? (courtesy of flickr user Arno & Louise)

One morning, the biologists were tracking a radio-collared lion when they observed two lions eating a western hartebeest. The lions fled the scientists’ car and hid while the humans were in the area. After a couple of hours, the scientists left the area. When they returned to the site in the late afternoon, the lions were gone, but there were several local people near the carcass. Like the lions, the people fled and hid when the scientists approached.

The hartebeest, which had been mostly intact in the morning, was now stripped of its meat. Cut marks indicated that this had been done by knife, not lion teeth. In addition, near the carcass there were fresh leaves, the kind of leaves that local people could have used to wrap the meat for transport. Though the scientists had no way of knowing if the lions had been chased off from their kill or simply left the hartebeest behind, they were certain that the locals had made off with the lions’ breakfast.

This encounter prompted the biologists to look for similar reports. They found a study in Uganda that reported nine cases of humans actively scavenging meat from lions and leopards. At a game reserve in Tanzania, local people, including some park staff, are known to obtain meat from lion kills. Taking meat from lions is thought to be a common practice among the nomadic Mbororo in North Cameroon. And, the scientists write, “one village in the Central African Republic is known to allow lions living in the surroundings, solely for easy access to meat.”

The extent of this practice across Africa is not known. The biologists worry, though, that it could be hurting the lions. From the BBC News:

“We believe that the impact of this kind of behaviour might be significant on lion populations, since lions have to spent an enormous energy effort to capture the same amount of prey, if their prey gets stolen,” says [Hans] de Iongh [of Leiden University]. “This may have a serious impact on a lion population which is already under serious stress by human encroachment and may eventually contribute to more rapid extinction.”

In [Cameroon’s] Waza National Park, for example, the population of lions is thought to have declined from 50 to 60 animals in the 1990s to between 12 and 20 in 2008, when the last survey was conducted.

Considering that an estimated six lions are killed each year by livestock owners and poachers, de Iongh and his colleagues fear that lions in the park are on the verge of going extinct.

Which paw does your cat favor? (courtesy of Flickr user tanakawho)

I tried an experiment this weekend, inspired by a new study about the handedness of cats. Psychologists from Queen’s University Belfast in North Ireland, in a study published in Animal Behaviour, conducted a series of experiments on 42 kitties to discover if they are left- or right-pawed.

In two of the experiments, in which the cats had to reach for a toy mouse, the kitties were ambidextrous. But in the third experiment—in which bits of tuna were placed in a jar for a cat to fish out—showed a definite paw preference: 20 out of 21 female subjects used their right paw, and 20 out of 21 male subjects used their left.

Inspired by these results, I decided to try out the tuna experiment on my own test subject: Sabrina, my 12-year-old female tortoiseshell. Like the cats in the Animal Behaviour paper, she would be tested in her home environment. My one concern was that she was older than the kitties in the paper, which ranged up to only eight years, but I didn’t think that would be a problem. And while she has never shown much desire for human food, she has enjoyed tuna in the past.

Attempt 1 (Saturday afternoon): Half a teaspoon of canned tuna is placed into a small, clean, empty mayonnaise jar. The jar is placed on the floor. Sabrina sniffs the tuna with interest but quickly turns away. The jar is left on the floor for an hour, but the subject finds napping more interesting. I wonder if the jar, which has a small lip, is too intimidating for the cat. Perhaps she did not see a way to remove the tuna. Or maybe she did not find the tuna appetizing.

Attempt 2 (Sunday afternoon): A teaspoon of canned cat food (Science Diet Baked Tuna Dinner) is placed in plastic cup (to eliminate the potential problem of the jar’s lip). The cup is placed on the floor. Again, Sabrina sniffs the offering but, unable to reach the food with her mouth, she turns away and goes to eat her dry food. She returns to the cup a short time later and sniffs it. She then settles for a nap within a foot of the cup.

Conclusion: Sabrina is either uninterested in the offered food or not smart enough to figure out how to obtain it. With attempt 1, the more likely explanation for her inability to reach the tuna is that she was not tempted enough by the tuna to retrieve it. With attempt 2, I suspect she knows that she does not have to try too hard to get the food out of the cup because she knew I would be feeding her the rest of the can in a short time. Cats may not be too smart, but they know enough about how their humans work to live very comfortable lives.

And now I not only have no idea about my cat’s handedness (although I suspect she is a rightie like most of the females in the Animal Behaviour study), I also was unable to obtain any video of the experiment. In its place, I offer a video from one of Smithsonian magazine’s readers of their cat:

Australian amateur astronomer Anthony Wesley was the first person to spot the new spot on Jupiter, on July 19th. Professional astronomers quickly confirmed the sighting and started aiming their powerful telescopes at the gas giant. Scientists now say that a small comet probably created the scar, which is about the size of the Pacific Ocean.

Although the spot appears black in visible-wavelength images, it glows in infrared, like in the image above (the new spot is the one in the bottom center). The picture was produced by astronomers using the Gemini North telescope on Mauna Kea in Hawai’i.

“We utilized the powerful mid-infrared capabilities of the Gemini telescope to record the impact’s effect on Jupiter’s upper atmosphere,” said Imke de Pater (University of California, Berkeley). “At these wavelengths we receive thermal radiation (heat) from the planet’s upper atmosphere. The impact site is clearly much warmer than its surroundings, as shown by our image taken at an infrared wavelength of 18 microns.”

The Gemini images were obtained with the MICHELLE spectrograph/imager, yielding a series of images at 7 different mid-infrared wavelengths. Two of the images (8.7 and 9.7 microns) were combined into a color composite image by Travis Rector at the University of Alaska, Anchorage to create the final false-color image. By using the full set of Gemini images taken over a range of wavelengths from 8 to 18 microns, the team will be able to disentangle the effects of temperature, ammonia abundance, and upper atmospheric aerosol content. Comparing these Gemini observations with past and future images will permit the team to study the evolution of features as Jupiter’s strong winds disperse them.

This is only the second time that astronomers have been able to see the effect of an impact on the Jupiter surface. They watched the planet closely when the Shoemaker-Levy 9 comet broke apart and collided with the gaseous surface 15 years ago this month.

Fifty years ago, Mary Leakey discovered the first known East African hominid. Image credit: Bettman/Corbis

The next time a creationist spouts some nonsense about how the lack of a fossil record undermines the theory of evolution, direct them to the hominid family tree. If you haven’t read much about human origins lately, it might come as a surprise that so many species have been identified (and more all the time).

One of the most important fossils, and one that marked an important turning point in paleoanthropology, was discovered 50 years ago this month by Mary Leakey. She (and her husband; I suppose we must mention him) spent decades looking for fossil hominids in Kenya’s Olduvai Gorge before finding their first: a skull of Australopithecus boisei, a.k.a. Paranthropus boisei, a.k.a. Zinjanthropus boisei, a.k.a. “Nutcracker Man,” which lived about 1.8 million years ago.

As the list of possible names suggests, paleonthropologists have argued quite a bit about exactly how to classify the various hominids. But this fossil clarified one important point. Before Mary Leakey’s discovery, many experts thought that hominids evolved in Asia. After her discovery, it was clear that hominids evolved in Africa. The newfound skull also showed that other poorly understood fossils, such as the Australopithecus africanus that had been discovered earlier in South Africa, were part of our own distinguished lineage rather than merely ancestors of apes.

Louis Leakey examines Australopithecus boisei. Image credit: Bettmann/Corbis

Smithsonian ran a story a few years ago about the absurdly paleoanthropologically prolific Leakey family, including son Richard who grew up digging for bones. It helps explain why it’s easier to find a photo of Louis showing off the Nutcracker skull than Mary:

Although Louis grabbed the headlines, it was his second wife, Mary, an archaeologist, who made many of the actual finds associated with the Leakey name. Until later in their relationship, when their marital ties all but snapped for both personal and professional reasons, she let her husband bask in the limelight while she conducted her beloved fieldwork….

Then, in 1959, came the now-famous discovery, in Olduvai, of a 1.75-million-year-old skull that Leakey named Zinjanthropus boisei, and which he asserted was the “connecting link between the South African near-men . . . and true man as we know him.” The skull was similar to those of the robust ape-man creatures that had been found in South Africa, but differed from them in having heavier bones and bigger teeth. Nearly three decades of work had at last been rewarded, it seemed, and the huge publicity surrounding the find propelled the Leakeys—particularly Louis, though Mary had actually discovered the skull—to still greater fame.

Here’s to the next 50 years of discoveries about human origins.

Edvard Munch’s Starry Night, 1893 (credit: The J. Paul Getty Museum, Los Angeles)

Forensic astronomer Don Olson solves puzzles. He looks at pieces of art, passages of literature and stories from history and uses science to answer questions like: Why is the sky red in Edvard Munch’s painting The Scream? (Gas and ash from the 1883 eruption of Mount Krakatoa produced colored skies worldwide.)

When I spoke to Olson last year (see “Celestial Sleuth” from the April issue), he said he was delving into the details behind three more Munch paintings and would soon be going to Norway. The results of his studies now appear in the August issue of the Griffith Observer.

The three paintings—Starry Night, The Storm and Sunrise in Åsgårdstrand—were created in 1893, according to detailed Munch chronologies. However, just when Munch visited to Norwegian coastal town of Åsgårdstrand during that year was unknown, and some biographers questioned whether he had visited the town at all in 1893. Astronomical details in the three paintings could provide some clarity in the matter.

Olson consulted personal accounts of Munch acquaintances, contemporary newspaper articles and historical photographs. He and his colleagues visited Åsgårdstrand to make a topographical survey of the town and to check out the views from various buildings. And they created computer simulations of the sky and parts of the town during Munch’s supposed time there.

“In one of the most moving moments of our trip, we realized we were standing on the same floorboards by the same window where the artist himself had looked out to watch the rising sun, more than a century before,” Olson writes.

Munch viewed the image he painted in Starry Night (which hangs in the Getty Museum in Los Angeles) from the center of the upper floor of Åsgårdstrand’s Grand Hotel, Olson and his colleagues determined. The group of linden trees on the right side of the painting still stands today. The white line in the trees, which some had speculated was the glitter path of the moon, was a flagpole with a round ball at the top. The pole is gone, but there is a depression in the grass that marks its former base. The stars in the upper left corner of the image include the planet Jupiter and the Pleiades. And based on the position of Jupiter and local weather reports, the painting likely shows the evening twilight of August 16 or 23, 1893.

The Storm (which can be seen on the Museum of Modern Art web site) depicts a woman in white in front of a building as a storm approaches. A single star can be seen in the upper right corner. An eyewitness wrote of Munch’s creating the image the day after a sudden change in the weather during August 1893. An Oslo newspaper wrote of the strong thunderstorm, which occurred on August 19. The building is the Grand Hotel, Olson’s group found, and the star is Arcturus, which would have appeared in that spot around 9:15 P.M. on the day of the storm.

Sunrise in Åsgårdstrand (which unfortunately sits in a private collection and cannot be seen online) shows a house with a view of the fjord beyond. A rising sun casts a glitter path on the water to the left of the house. A small building below this path is a boathouse. Olson discovered that almost this exact scene could be seen from the upper floor of Soelberggården, a house near the one depicted in the painting and which was once owned by one of Munch’s friends. The trees in the image are now taller, and the house has had a dormer added, but historical photographs helped to match up the view. The sun would have appeared in the spot where Munch painted it only during the first week of April 1893, when he is known to have been in Germany, and the first five days of September. The only day when the weather matched the September dates, though, was September 3, and the sun shone at that spot in the sky at 5:30 A.M.

Munch, therefore, must have visited the coastal town for at least a three-week period in 1853, between mid-August and early September.