August 11, 2011
In the new movie Rise of the Planet of the Apes, the leader of the ape revolution can talk. In the real world, apes can’t speak; they have thinner tongues and a higher larynx, or vocal box, than people, making it hard for them to pronounce vowel sounds. But that doesn’t necessarily mean they don’t have the capacity for language—sign language, after all, doesn’t require any vocalization.
Over the years, researchers have succeeded—and failed—in teaching apes to use language. Here’s a look at some of the more famous “talking” apes.
Viki: Viki, a chimpanzee, came closest to being a real talking ape. In the late 1940s and early 1950s, Keith and Catherine Hayes of the Yerkes Laboratories of Primate Biology, then located in Orange Park, Florida, adopted Viki and raised her at home as if she were a human baby. With the Hayeses moving her lips for her, Viki learned to utter “mama.” Eventually, with much difficulty, she managed to say three other words—papa, cup and up—on her own. Viki’s tenure as a talking ape didn’t last long; she died at the age of seven of viral meningitis.
Washoe: In the 1960s, psychologists Allen and Beatrix Gardner of the University of Nevada, Reno recognized that chimpanzees naturally gesture a lot and thought chimps would be well suited for sign language. In 1966, they started working with Washoe. Later, psychologists Roger and Deborah Fouts, now retired from Central Washington University, continued the work. By the end of Washoe’s life in 2007, she knew about 250 signs and could put different signs together to make simple combinations like “Gimmie Sweet” and “You Me Go Out Hurry.” Washoe’s adopted son Loulis also learned to sign—by watching his mother. He was the first ape to learn signs from other apes, not humans. For more on Washoe’s life, read Roger Fouts’ Next of Kin.
Nim: After the success with Washoe, psychologist Herbert Terrace of Columbia University decided to replicate the project. At first, Nim—full name Nim Chimpsky, named after linguist Noam Chomsky who thought language was unique to humans—was raised in a human household. (Washoe had been treated like a person too but had her own trailer.) Later, Nim was removed from the family and his language lessons moved to a lab on Columbia’s campus. In the end, Terrace concluded Nim never really learned language; he had merely been trained to imitate his teachers to get rewards. The sad story of Nim’s life after the project ended is told in the new documentary Project Nim.
Chantek: Chimpanzees are not the only talking apes. In 1978, anthropologist Lyn Miles of the University of Tennessee at Chattanooga began studying an orangutan named Chantek. During eight years of study, Chantek learned 150 signs. He also showed signs of being self-aware: he could recognize himself in a mirror. Today, you can visit Chantek at Zoo Atlanta, his home since 1997.
Koko: Koko the gorilla is probably best known for her love of kittens and Mr. Rogers (and maybe less well-known for her encounter with Captain James T. Kirk). Koko’s sign-language training began in 1972 with then-graduate student Francine (Penny) Patterson of Stanford University. According to the Gorilla Foundation, Koko knows 1,000 signs and understands spoken English. It also claims the gorilla has an IQ somewhere between 70 and 95 (the average human IQ is 100). (Critics, however, remain skeptical about some of Koko’s supposed abilities due to the lack of recent scientific publications supporting the claims. (PDF))
Kanzi: Kanzi, a bonobo, doesn’t use sign language; he uses different combinations of lexigrams, or symbols, to communicate. In the early 1980s, psychologist Sue Savage-Rumbaugh, then of Georgia State University, was trying to teach Kanzi’s mom, Matata, to use the lexigrams; instead, Kanzi was the one who mastered the symbols. Kanzi understands spoken English and knows close to 400 symbols. When he “speaks,” his lexigram usage follows rules of grammar and syntax, according to researchers at the Great Ape Trust in Iowa, where Kanzi now resides. Kanzi is also an accomplished stone-tool maker.
July 20, 2011
For “Predator Week,” I wanted to highlight some unlikely fearsome creatures: venomous mammals. These mammals are a bizarre bunch. The male platypus has spurs on its ankles that release venom, likely to fight off male competitors during mating season. And various species of shrew and the shrew-like solenodon use venomous saliva to disable prey.
The solenodon is particularly fascinating because it delivers its poison just as a snake does—using its teeth as a syringe to inject venom into its target. Not a lot is known about these unusual mammals. There are only two solenodon species: One lives on Cuba and the other on Hispaniola (home to Haiti and the Dominican Republic). At night, they dig in the dirt with their Pinocchio snouts and long claws, looking for grub and waiting to disarm their prey—insects, worms, snails and small frogs and reptiles—with a toxic bite. The BBC has some great video footage of the strange little guys (the solenodon’s venom isn’t lethal to people but notice the handlers still wear gloves).
It readily defends itself against one of its own kind, and probably attacks other animals savagely judging from the way a captive solenodon attacked a young chicken and tore it to pieces with its strong claws, before eating it.
Millions of years ago, venomous mammals may have been more common. But soon the world may lose a couple more: Like many other predators, both species of solenodon are highly endangered. Deforestation and the introduction of dogs, cats and mongooses that eat solenodons threaten to drive the critters to extinction. And in Haiti, people hunt solenodons for food.
Fortunately, the solenodon has recently become the focus of conservation efforts. It would be sad if such a unique, mysterious mammal were gone for good—although I imagine the invertebrates of the Caribbean wouldn’t mind.
Tomorrow in Predator Week: Scientists find the marine version of the Serengeti’s great migrations
July 8, 2011
The four astronauts aboard the space shuttle Atlantis will not be alone when they blast into space today (assuming the launch proceeds as scheduled). The last shuttle mission will also carry 30 mice that are part of an experiment to better understand why astronauts lose bone mass when they hang out in low-Earth orbit.
The mouse study is typical of the type of research that seemed to dominate space shuttle science: investigations devoted to figuring out how the human body—and the microbes that parasitize us—cope with space. It’s the kind of work that’s necessary if we want to safely send people on long-term missions to Mars and beyond.
With all of the talk about the end of the space shuttle program, I wondered what other science has happened aboard Atlantis, Challenger, Columbia, Discovery and Endeavour. I found some surprises. Here are my favorite quirky space shuttle science projects:
A rose in space smells as sweet—or sweeter: The fragrance of flowers comes from the plants’ essential oils. Many environmental factors influence the oils that a flower produces—and one of those factors is apparently gravity. In 1998, the perfume manufacturer International Flavors & Fragrances sent a small rose called Overnight Scentsation into space aboard Discovery. Astronauts grew the rose in a special chamber and collected its oils. In the low-gravity conditions of Earth’s orbit, the flower made fewer essential oils, and the oils it did produce smelled different (a “floral rose aroma” instead of “a very green, fresh rosy note”). Back on Earth, the perfume company synthesized the rose’s space oils to create a new fragrance that is now in Shiseido’s perfume called Zen.
The MGM experiment: MGM doesn’t refer to the movie studio or the Las Vegas casino; it stands for “Mechanics of Granular Materials.” With this experiment, researchers in space studied the effects of earthquakes, sort of. On three shuttle missions, the MGM experiment compressed columns of sand to allow researchers to study the sand’s strength and other mechanical properties. Such properties are relevant to many processes on Earth, such as soil liquefaction. Liquefaction is often a problem during earthquakes: the shaking increases the external forces acting on any water in the ground, causing water pressure to go up. The higher water pressure weakens the soil, making it flow like a liquid and causing buildings to sink. Studying sand in space is beneficial because the lower gravity reduces certain stresses that make it difficult to study liquefaction and similar phenomena on Earth. Sadly, the last MGM experiment flew aboard the Columbia mission that broke up during re-entry in 2003.
The Tunguska mystery solved: Technically, this piece of science didn’t occur aboard the space shuttle, but it certainly benefited from the shuttle program. In 1908, an extraterrestrial object hit Russia, flattening almost 3,500 square miles of Siberian forest near the Podkamennaya Tunguska River. Scientists have debated whether an asteroid or comet caused the impact. Space shuttle exhaust points to a comet. Researchers at Cornell University and Clemson University made the connection after noticing the formation of noctilucent (“night shining”) clouds following two shuttle launches. The brilliant clouds likely formed from the hundreds of tons of water vapor emitted from the shuttle’s engine during takeoff. Historical records note that the night sky similarly lit up after the Tunguska event. The researchers say noctilucent clouds were probably the cause of the glow, suggesting that whatever hit Earth must have released a lot of water into the atmosphere. This makes comets the likely culprit because they, unlike asteroids, carry a lot of ice.
These scientific experiments are fun, but do they justify the hefty price tag of the shuttle program? Probably not. Some might say the program’s greatest scientific achievements relate to the satellites that astronauts brought to space or the repairs they made to the Hubble Space Telescope.
I’ll suggest another achievement, one that’s more personal. As someone who grew up during the shuttle’s early days, the program helped steer me down a scientific path. It certainly helped foster my interest in learning about the world around (and above) me.
June 22, 2011
We humans aren’t alone in our aversion to snakes. Our primate cousins also fear serpents. And for good reason—snakes eat primates. Snakes have been preying on primates for millions of years, and some researchers think they might be the reason we—and our fellow primates—have such good eyesight.
Good vision is a hallmark of the primate order. Compared with many other mammals, primates have more closely spaced, forward-facing eyes that allow for a lot of overlap between each eye’s visual field, which in turn gives primates 3-D, or stereoscopic, vision and a good sense of depth perception.
In the early 20th century, scientists attributed primates’ keen sense of sight to their arboreal lifestyle. The ancestors of primates needed to accurately judge the distances between tree branches before taking a leap, so the theory went. But that hypothesis lost favor in the 1970s after biological anthropologist Matt Cartmill, now at Boston University, pointed out that many other acrobatic, tree-dwelling animals like squirrels get by without such an advanced visual system.
Cartmill offered his own explanation, called the “visual predation hypothesis”: early primates needed superb visual skills to hunt and grab insects. Another hypothesis is that primates needed to see well to pluck fruits from the ends of tree branches.
More recently, snakes came into the picture. In 2006, anthropologist Lynne Isbell of the University of California at Davis argued that early primates were stalked by constricting snakes, and it was highly beneficial to see these camouflaged predators before it was too late. Later, some monkeys and apes in Africa and Asia started to live alongside venomous snakes, which led to even more visual advancements.
But the idea may not hold up, according to the authors of a recent study in the Journal of Human Evolution. Led by behavioral ecologist Brandon Wheeler of the Cognitive Ethology Laboratory at the German Primate Center, the team tested the snake hypothesis by looking at variations in modern primates’ visual skills (in terms of stereoscopic vision, as measured by the closeness of the eyes) to see if the primates with the best eyesight had the longest evolutionary history of coexisting with snakes and the greatest likelihood of encountering and being attacked by them.
The team didn’t find any correlations between snake exposure and primate vision, concluding that snake attacks did not drive the evolution of better eyesight. Still, the researchers say, detecting snakes was definitely a beneficial side effect regardless of why better vision evolved.
June 21, 2011
Archaeologists often talk about the importance of trash—you can learn a lot about a culture by looking at what it threw away. Chemists may say the same thing about another kind of waste: sewage. Throughout last year, researchers at the Norwegian Institute for Water Research monitored the illegal drug habits of half a million people in Oslo by chemically sifting through the sewers. The work is an example of the emerging field of “sewage epidemiology.”
The research field has developed over the past decade (Popular Science has a good article on the early days). The idea is that screening for drugs that pass through the body and then get flushed down the toilet may be one of the fastest, most accurate ways to assess a community’s drug use. After all, people can lie in surveys, and segments of the population can be overlooked. It’s harder to manipulate what goes into the sewers (although I can imagine that if sewage epidemiology really takes off, paranoid drug users may look for alternative ways to get rid of their personal waste).
In the Norwegian study, published online in the journal Environmental Science & Technology, Christopher Harman, Malcolm Reid and Kevin Thomas placed chemical samplers in a wastewater treatment plant and, over the course of a year, looked for cocaine, amphetamine, methamphetamine, Ecstasy and the chemicals that these drugs break down into during digestion. They found some interesting results. For example, concentrations of cocaine went up on the weekends, and Ecstasy spiked in the month of May. The researchers note that this peak coincided with “russefeiring,” a two-week celebration for recent high school graduates.
Based on the concentrations of each drug—and knowing certain factors like how much of a drug gets excreted by the body—the team calculated backward to figure out drug usage. For cocaine, daily consumption averaged between 0.31 and 2.8 grams per 1,000 inhabitants. The researchers say this is in line with estimates from Spain.
The Norwegian study looked only at one wastewater treatment plant that serves much of Oslo and three neighboring areas, but other studies have tracked drug usage over a much larger area. In 2008, researchers collected samples from 96 municipalities in Oregon, accounting for 65 percent of the state’s population. They found that cocaine use was much higher in urban areas whereas methamphetamine was found everywhere.
The Oregon study was only a one-day snapshot of drug habits. But if such a study were maintained over time, sewage epidemiology could be a powerful drug-tracking tool for law enforcement. As the Popular Science article points out, such analyses could allow officials to evaluate the effectiveness of anti-drug campaigns or follow drug supply lines.
The possibility of constant wastewater monitoring may make some people uncomfortable, but I find it fascinating that scientists can track a range of behaviors—from prescription drug use to preferences in cosmetics—with a test tube of sewer water. I wonder what sewage epidemiologists will be looking for next.