Orcinus orca. Image by Flickr user *christopher*

When I was a kid, I saw a photograph in an old Life magazine of a man standing on the ice somewhere in the Arctic, and a killer whale breaking trough the ice, much of the whale’s body out of the water, a very short distance from the man. The whale was so close to the man that it was hard to say if the wincing expression on his face was due to being splashed with cold seawater or the thought that he was about to be ruthlessly mauled and eaten by the most vicious and dangerous creature on Earth.

Those were the days, of course, when we called these big sea mammals “killer whales” instead of “orcas,” a term many people use now to help the animals’ reputation and enhance conservation efforts. In the old days we knew that if you were anywhere near the ocean a killer whale would thrust through the ice and grab you and eat you. Later we learned that killer whales eat only fish and are never a threat to humans. Somewhere in there was the film Free Willy, which I never saw but assume showed these large members of the dolphin family to be good guys instead of bad guys.

It is now the 21st century, however, and we have a more sophisticated view of wildlife and animal behavior. It is no longer necessary to protect the reputations of predators in order to convince people to appreciate them for what they are, and it is fairly rare these days (though not yet rare enough) to see conservation policy based on fear rather than science.

Meanwhile, knowledge of Orcinus orca dietary behavior is increasing, and the behavior turns out to be quite complex. For instance, killer whales in the Northwest coastal regions are in fact mainly fish eaters, but migratory whales that move in and out of that region tend to eat mammals. The following three unusual principles seem to be emerging:

1. Any given group of these whales specializes in a type of food, and a group doesn’t change its dietary pattern very much over time.
2. There is a wide range of potential specializations, ranging from fish to seals or sea lions to smaller whales to larger whales.
3. Different social groups can be found in the same waters at the same time, with different specializations for feeding.

The killer whales that live in the far north, mostly in the Arctic Circle, have been studied the least of all, so their dietary preferences and overall relationship to the rest of the ecosystem is not as well known as it is for other groups. Also, with global warming, it appears that killer whales are either newly colonizing some of the waters in these northern regions, or spending more time there than before. To sum up: Killer whales have complex, variable behavior that cannot be assumed without direct observations; a large region in which they live lacks intensive research; and things may be changing in that region. Thus the significance of a very interesting paper, just out, by Steven H. Ferguson, Jeff W. Higdon and Kristin H. Westdal.

The researchers employed a method called “Traditional Ecological Knowledge” to characterize the diet and behavior of killer whales in Nunavut, Canada. People who live in a region often know a lot about its environment. This is, of course, not always true. For instance, here in Minnesota, the bears are all Ursus americanus, also known as “black bears.” But their fur color varies a lot, so there are whitish ones, brownish ones and even blond ones. A lot of Minnesotans think we have two kind of bears here, black and brown, incorrectly assuming that a black bear that is brown is Ursus arctos, the brown bear. The point is, I would not trust a randomly chosen Minnesotan to be able to accurately list which members of the order Carnivora live in their own state, let alone to describe the animals’ diet or behavior.

When I lived with the Efe Pygmies in the Ituri Forest of Congo, the opposite was true. The Efe really knew the animals and their behaviors. It took some patience and expertise (as a trained anthropologist) on my part to get through some of the cultural confusion. For instance, every person has a “totemic” animal, an animal into which deceased ancestors can manifest now and then, and some of these animals were imaginary. But I quickly learned to identify the imaginary animals because in every case there is only one of them, and it lived in a particular spot out in the forest somewhere. Otherwise, however, the Efe had what I would regard as perfect taxonomic knowledge and extensive behavioral knowledge of all of the mammals and birds in in the rain forests in which they lived.

In one instance, the Efe talked about a chameleon that made a “woo woo woo” noise during the full moon, but that was otherwise impossible to find. We scientists, however, knew that chameleons were always silent. There are no vocalizing species of chameleons, so this was impossible. Of course, we would hear this animal every full moon, but assumed it was some kind of as yet unidentified frog or something. Maybe even a bird.

Then, one day, Western scientists discovered this African chameleon that said “woo woo woo” during the full moon. Turns out the Efe were right all along, and we had egg on our scientific faces.

The study at hand points out that killer whale preferences for prey are largely unknown in the eastern Canadian Arctic. To remedy this, the researchers surveyed native Inuit people to develop an understanding of Inuit Traditional Ecological Knowledge (TEK) regarding killer whale feeding ecology. They conducted more than 100 interviews in 11 Nunavut communities in the Kivalliq and Qikiqtaaluk regions during the period from 2007 to 2010.

The Inuit knew about what the whales ate, how they hunted and captured prey, how the prey responded to the whales and when and where predation events occurred. The information provided by the Inuit agreed with the available published literature and expanded on it. For instance, both the TEK and the published information agreed that killer whales sometimes eat only certain parts of their prey, especially in the case of large whales. Also, small groups of killer whales, acting cooperatively, would attack large whales. The Inuit data suggested that the whales took any and all sea mammals, and in this area, either did not eat fish or hardly did so (it had not been observed).

From the published paper:

By combining TEK and scientific approaches we provide a more holistic view of killer whale predation in the eastern Canadian Arctic relevant to management and policy. Continuing the long-term relationship between scientists and hunters will provide for successful knowledge integration and has resulted in considerable improvement in understanding of killer whale ecology relevant to management of prey species. Combining scientists and Inuit knowledge will assist in northerners adapting to the restructuring of the Arctic marine ecosystem associated with warming and loss of sea ice.

In the distant past, scientists often ignored and even made fun of the knowledge of indigenous people. But we now recognize that people who live off the land for generations know more than researchers will discover with years of investigation. If you ask, “should we ignore the vast knowledge of the native people of the Canadian Arctic” the only good answer is, “No, we’ll have Nunavut.”

Ferguson, S., Higdon, J., & Westdal, K. (2012). Prey items and predation behavior of killer whales (Orcinus orca) in Nunavut, Canada based on Inuit hunter interviews Aquatic Biosystems, 8 (1) DOI: 10.1186/2046-9063-8-3

Editor’s Note: Thanks to our readers for catching an error in our original headline. Inuit is indeed the plural form — not Inuits. The error has been fixed. Thanks — BW

Australopithecus sediba had a hand built for making stone tools (picture by Peter Schmid; courtesy of Lee Berger and the University of Witwatersrand)

Australopithecines lived in Africa some 4 million to 2 million years ago. Scientists speculate that the australopithecines gave rise to our own genus, Homo, sometime around 2 million years ago, but there’s not much fossil evidence to show exactly when or how this happened. But last year, scientists led by Lee Berger of the University of Witwatersrand announced they had found a possible candidate ancestor of Homo: Australopithecus sediba. The species lived 1.977 million years ago and resembled Homo in many ways.

This week, the researchers published five papers in the journal Science that provide a more in-depth look at the species. Experts are excited about the fossils, but do not agree on where A. sediba belongs in the human family tree—and in some sense, its discovery muddies the picture of human evolution at this critical transition 2 million years ago.

The new studies analyze two partial skeletons found in Malapa Cave in South Africa: a 12- to 13-year-old male and an adult female. Here’s a rundown of the key findings:

Brain: The researchers studied the size and shape of the young male’s brain by taking X-ray scans of his skull and creating a virtual 3-D endocast. A. sediba had a small brain—420 cubic centimeters—only slightly bigger than a chimpanzee brain or half the size of a Homo erectus brain. But the shape and organization of part of the frontal lobe appear similar to Homo. The team says this may mean brain reorganization came before a big jump in brain size in humans.

Pelvis: The pelvis had a mix of australopithecine- and Homo-like traits. This is interesting because some of A. sediba’s more advanced traits, like the shape and orientation of the ilium, were thought to have evolved in the genus Homo to accommodate bigger-brained babies as they came through the birth canal. But since A. sediba had these features and a small brain, another factor probably drove the evolution of these traits; they could be the result of spending even more time walking on the ground and less time in the trees, the researchers suggest.

Hands and Feet: The team found a nearly complete wrist and hand for the species as well as a partial foot and ankle. The foot had a unique mix of traits not seen in any other hominid, suggesting A. sediba had its own form of upright walking and probably still climbed trees. The hand also indicates A. sediba was a climber, but it shows that the hominid had the musculature and anatomy necessary for a “precision grip,” when the thumb meets the fingertips. This movement is what allows you to thread a needle or hold a pencil—and it probably enabled A. sediba to make and use stone tools, the researchers say, although they have not yet found any tools with the species.

Here’s why A. sediba complicates things. For the species to be the ancestor of Homo, it had to have lived before the first species of that genus. That’s just common sense. And it’s true for what the researchers call the “earliest uncontested evidence” of Homo: Homo erectus, at 1.9 million years ago.

But then there’s the contested evidence. At roughly 2.4 million years ago—before A. sediba— a species called H. habilis (“handy man”) lived in Africa, although the researchers say there is disagreement over what fossils should be included in this species. If this handy man is really the earliest member of Homo, it’s hard to call A. sediba an ancestor (unless, perhaps, additional fossil finds push back A. sediba’s age).

In some ways, H. habilis is more human-like than earlier hominids; it had a much larger brain, for example. But in other ways, such as the anatomy of the hand, A. sediba is more human-like than H. habilis, Berger and his colleagues say. What does this all mean? It’s unclear. But at the very least, several different types of Homo-like hominids probably all lived at about the same time—making it a “most challenging endeavor,” the researchers say, to figure out how these forms relate to each other and which if any best represents the ancestor of our genus.

As paleoanthropologists like to say, more fossils may help clarify things—or muddle them even more.

Kanzi the bonobo is quite the musician. Image courtesy of the Great Ape Trust

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.

Scientists are still trying to figure out why primates have excellent vision. (langur monkey photo courtesy of flickr user Troup Dresser)

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.

A crowd in India, courtesy of Flickr user seeveeaar

The United Nations announced this week that the world population is expected to reach 10 billion by the end of the century—and then just keep on growing (more details in the pdf). That’s a big increase from the previous estimate of a peak of 9 billion that would then stabilize or shrink.

Science magazine has a helpful Q&A that explains where these 1 billion previously unanticipated people of the future come from. Some of it is good news: fewer people are dying from AIDS than expected. Some less so: many family planning programs were abandoned in the past 20 years.

The new report is awash in data; it can be broken down by fertility and mortality models, age range and country. Like anyone who uses Google Earth for the first time, I immediately looked for home: the U.S. population should reach almost half a billion by 2099. That’s a lot of people, but the new numbers don’t really change the predictions for U.S. demographics in 2050 that Joel Kotkin made in Smithsonian magazine last year. That story was pretty optimistic: growth is better than decline; technology will make life better; immigrants will revitalize American culture. Here’s a taste:

Political prognosticators say China and India pose the greatest challenges to American predominance. But China, like Russia, lacks the basic environmental protections, reliable legal structures, favorable demographics and social resilience of the United States. India, for its part, still has an overwhelmingly impoverished population and suffers from ethnic, religious and regional divisions. The vast majority of the Indian population remains semiliterate and lives in poor rural villages. The United States still produces far more engineers per capita than India or China.

One of the least anticipated developments in the nation’s 21st-century geography will be the resurgence of the region often dismissed by coastal dwellers as “flyover country.” For the better part of the 20th century, rural and small-town communities declined in percentage of population and in economic importance. In 1940, 43 percent of Americans lived in rural areas; today it’s less than 20 percent. But population and cost pressures are destined to resurrect the hinterlands. The Internet has broken the traditional isolation of rural communities, and as mass communication improves, the migration of technology companies, business services and manufacturing firms to the heartland is likely to accelerate.

In discussing population growth, there’s a perpetual tension between economists (who consider an ever-expanding economy and workforce the greatest good) on one side and geologists, population biologists and environmentalists on the other (who point out that resources are limited, and in some cases we’re reaching the limit). The most immediate challenge posed by an increasing population, even today and certainly by mid-century or beyond, will be feeding all of these people.

A zombie walk in Chile in 2010 (courtesy of flickr user rodolpho.reis)

Zombies seem to be only growing in popularity, and I’m not talking about the biological kind. They’ve got their own television show, plenty of films, and even a musical. They invaded the world of Jane Austen, and there are zombie crawls around the world, in which people dress up like the living dead and shuffle across some urban area.

And then there’s the growing field of zombie science.

In 2009, University of Ottawa mathematician Robert J. Smith? (and, yes, he really does include a question mark at the end of his name) published a paper in a book about infectious disease modeling titled “When Zombies Attack! Mathematical Modelling of an Outbreak of Zombie Infection” (pdf). It started as a class project, when some students suggested they model zombies in his disease modeling class. “I think they thought I’d shoot it down,” Smith told NPR, “but actually I said, go for it. That sounds really great. And it was just a fun way of really illustrating some of the process that you might have in modeling an infectious disease.” Using math, the group showed that only by quickly and aggressively attacking the zombie population could normal humans hope to prevent the complete collapse of society.

That paper sparked further research. The latest contribution, “Zombies in the City: a NetLogo Model” (pdf) will appear in the upcoming book Mathematical Modelling of Zombies. In this new study, an epidemiologist and a mathematician at Australian National University refine the initial model and incorporate the higher speed of humans and our capacity to increase our skills through experience. They conclude that only when human skill levels are very low do the zombies have a chance of winning, while only high human skill levels ensure a human victory. “For the in-between state of moderate skill a substantial proportion of humans tend to survive, albeit in packs that are being forever chased by zombies,” they write.

Then there’s the question of whether math is really the most important discipline for surviving a zombie attack.

But how might zombies come about? There are some interesting theories, such as one based on arsenic from Deborah Blum at Speakeasy Science. Or these five scientific reasons a zombie apocalypse could happen, including brain parasites, neurotoxins and nanobots.

A Harvard psychiatrist, Steven Schlozman, broke into the field of zombie research and then wrote The Zombie Autopsies: Secret Notebooks from the Apocalypse, which blames an airborne contagion for the zombie phenomenon. The book delves into the (fictional) research of Stanley Blum, zombie expert, who searched for a cure to the zombie epidemic with a team of researchers on a remote island. (They were unsuccessful and succumbed to the plague, but nicely left their research notes behind, complete with drawings.) It’s more than just fun fiction to Schlozman, though, who uses zombies to teach neuroscience. “If it works right, it makes students less risk-adverse, more willing to raise their hands and shout out ideas, because they’re talking about fictional characters,” he told Medscape.

For those interested in getting an overview of the science, a (spoof) lecture on the subject, Zombie Science 1Z, can now be seen at several British science and fringe festivals. Zombiologist Doctor Austin, ZITS MSz BSz DPep, lectures in three modules: the zombieism condition, the cause of zombieism, and the prevention and curing of zombieism. And for those of us who can’t attend in person, there’s a textbook and online exam.

And the Zombie Research Society keeps track of all this and more, and also promotes zombie scholarship and zombie awareness month. Their slogan: “What you don’t know can eat you.”

How could early humans--and fish--have traversed the Sahara? (image courtesy of flickr user matteo_dudek)

The Sahara would seem to be an effective barrier for migration of anything other than birds. And so many scientists have assumed that early humans made their trek out of Africa—on their way to spread over the rest of the world—through the lush Nile River valley. However, there is little evidence that early humans actually took that route.

But there have been tantalizing clues that the Sahara has not always been the huge desert obstacle it is today. There are Nile crocodiles, fish and molluscs living in isolated Saharan oases, for example. How did they get there?

In a new study in PNAS, scientists from the United Kingdom say that the Sahara has gone through humid periods during which there have been lakes, rivers and inland deltas, all linked together and channeling water and creatures across the land. This vast waterway would have allowed the dispersal of animals, and with the animals, humans followed.

The last time this linked waterway was filled was in the early Holocene, around 10,000 years ago. The researchers examined the distributions of stone points and various Nilo-Saharan languages and found that the movement of humans during this last humid period was influenced by the movement of aquatic species; the human hunters were following their prey into what had been desert.

Whether humans were able to pass through the Sahara even earlier isn’t clear—there just isn’t enough data to show that there were earlier periods where the whole regions was wet—but there is evidence that a “green Sahara” may have existed around 100,000 to 125,000 years ago, around the time when modern humans were migrating out of the continent.

(HT: 80beats)

Three Koro speakers at a house in Kichang village in Arunachal Pradesh, India (Photo by Chris Rainier)

There are times when I wish that everyone in the world spoke the same language. I’m in awe of people who have mastered languages other than their own because I find it so difficult. While I might want English spoken everywhere I visit for my own ease, though, I’m also saddened by the loss of any of the thousands that currently exist. These languages are windows into the lives, histories and cultures of the people who speak them. Researchers estimate that at least half of the world’s 6,909 recognized languages are endangered, and one language dies out about every two weeks.

But as scientists rush to document languages before they disappear, sometimes the scientists also make incredible discoveries. This week two National Geographic Fellows announced that they had discovered a new language—called Koro—in the remote northeastern state of Arunachal Pradesh in India. That area of the world is considered a “language hotspot,” host to a diversity of little-studied languages, often ones that have no written counterpart.

The researchers had gone to Arunachal Pradesh to study two poorly known languages, Aka and Miji, when they detected the third. Koro has a distinct set of sounds and word combinations, and the structure of words and sentences is also different. (Example: a pig is called a “vo” in Aka and a “lele” in Koro.) Despite the differences, though, area speakers consider Koro a dialect of Aka. The scientists hypothesize that the two are connected by the regions’s historical slave trade: Aka was spoken by the slave traders and Koro may have developed among the slaves.

Koro may not survive much longer, however. Only about 800 people currently speak the language, few under the age of 20, and it has not been written down.

Including oodles of science.

Philippine Boy Scouts participating in Operation Moonwatch, a program to track artificial satellites that was inaugurated by the Smithsonian Astrophysical Observatory during the International Geophysical Year in 1957. Photo courtesy of Smithsonian Archives

It would be impossible to do justice to every volunteer’s work—each volunteer at Smithsonian does something especially fascinating—but here is a list of 10 of the top science-based volunteer gigs around the Mall and beyond:

Volunteer Forensic Anthropologist

After working in the department of anthropology at the National Museum of Natural History under forensic anthropologist and division head Doug Owsley, Sarah Spatz Schlachtmeyer wrote a book about her activities. A Death Decoded: Robert Kennicott and the Alaska Telegraph untangles the mystery of young scientist Robert Kennicott’s death as he was exploring the Yukon River more than 150 years ago. No bones about it, volunteering time to fiddle around with human skeletal remains is definitely one of the more fascinating opportunities at the Smithsonian.

Volunteer Amphibian Research Biologist

The Smithsonian Tropical Research Institute in Panama offers opportunities for aspiring (and veteran) biologists. For example, Roberto Ibanez, STRI’s leading amphibian research biologist, runs the Panama Amphibian Rescue and Conservation project, which rescues and establishes captive colonies of threatened and endangered amphibian species. Volunteers help to feed and house the amphibians. The project is just one of many programs at STRI actively seeking a large volunteer base. The 40 permanent scientists at STRI host nearly 1,000 visiting scientists every year and have projects in more than 40 tropical countries, with massive potential for anyone interested in volunteering.

Volunteer Entomologist and Tarantula Handler (Arachnologist)

Volunteers with the National Museum of Natural History’s O. Orkin Insect Zoo (no it’s not an attempt at irony, the extermination company contributed funds to the bug menagerie) regale visitors with insect factoids and, yes, put on live shows with the zoo’s many tarantula residents. These volunteers attempt to “make connections between visitors and these seemingly alien creatures,” says Bridget McGee-Sullivan NMNH volunteer manager. It’s certainly not the volunteer position for me, though (I kept my distance from the eight-legged monsters, even with a quarter-inch pane of glass in between us); I would much prefer the Butterfly Pavilion.

Volunteer Primatologist

One of the many behind-the-scenes volunteer positions at the National Zoological Park—jobs that include collecting panda dung for study and keeping tabs on the intricacies of flamingo behavior—is golden lion tamarin monitor. Though the tamarins have not been ranging free this summer across the grounds of the zoo, usually they are tracked by a dedicated corps of volunteers who take notes on the Brazilian primates and explain to visitors their endangered status, part of the zoo’s nearly 40-year project of golden lion tamarin conservation.

Each month more than 450 people volunteer through Friends of the National Zoo, says Mike Frick, who manages FONZ’s Behavior Watch program. They donate their time and energy to help zoo staff care for and collect scientific data on the animals exhibited at the zoo and those located at the zoo’s Front Royal, Virginia campus, the Smithsonian Conservation Biology Institute.

Data collected by volunteers is used for national conservation efforts, monitoring breeding behavior of the zoo’s animals, helping zoo keepers prepare diets for the animals and “research into the life history of animals that are either so rare or elusive in the wild that studies on captive individuals are the only means by which scientists have to understand them,” Frick says.

Volunteer Horticulturalist

Amateur gardeners, retired botanists and other interested individuals can find a place to call home among the fecund gardens of the National Zoo. The Pollinarium, Heritage Gardens and Butterfly Garden are home to a vast array of wild and rare plants and flowers that all need gardening and care. Volunteer horticulturalists can also be found beyond the zoo’s grounds; eight Smithsonian gardens are located around the National Mall, all requiring dedicated volunteers to tend.

Volunteer Forest Ecology Researcher

At the Smithsonian Environmental Research Center on the Chesapeake Bay, bank executives and other volunteers gather data from Maryland’s forests on how it is being affected by logging and climate change. There are 18 research laboratories at SERC studying topics that range from earthworms to native orchids to forest ecosystems, says SERC outreach coordinator Karen McDonald. SERC usually hosts 60 to 90 volunteers, depending on the season, who take part in tasks that include tagging blue crabs and building fences to limit deer movement  for studying the effects they have on their ecosystem.

Volunteer Planetary Geologist

Throughout the National Air and Space Museum, volunteers are strategically placed with 12 “Discovery Carts” giving demonstrations on all manner of topics, such as aviation and astrophysics, allowing visitors to interact with items that relate to the collection. One standout is the falling-stars cart, which lets visitors touch pieces of meteorite that have made their way to Earth from around the solar system. Visitors learn from the cart’s volunteer planetary geologists about these meteorites and what their different properties and chemical make-ups can tell us about our solar system. “There’s something magical about handing someone a rock that looks like a piece of coal then seeing their face when you tell them that it’s as old as the solar system,” Tom Hill, an NASM volunteer, told discovery station program coordinator Beth Wilson.

National Museum of Natural History's Anthropology Conservation Laboratory volunteer Edith Deitz (right) looking at an artifact in the laboratory with staff members in 1977. Photo by Victor Krantz, courtesy of Smithsonian Archives

Volunteer Chemist and Innovation Facilitator

At the National Museum of American History’s Spark!Lab, volunteers encourage the young and young-at-heart to express their own inventiveness. Volunteers and staff facilitate interactive experiments in chemistry, physics and genetics. It’s just the place for a volunteer mad scientist.

Around the Mall talked to Spark!Lab’s “Resident Eccentric,” Steven Madwell, a couple of years ago.

Volunteer Naturalist

Volunteers at the Smithsonian’s Naturalist Center in Leesburg, Virginia, spend their days answering questions of inquisitive minds, from kindergartners to high school seniors. “Every day is an adventure for Naturalist Center volunteers,” NMNH’s McGee-Sullivan says. “You never know who will walk in the door and what type of question will be asked of a volunteer.” One five-year-old girl brought in a partial skull from the playground, McGee-Sullivan says. The volunteers at the Naturalist Center helped her discover that it was the skull of a cottontail rabbit.

Volunteer Zoologist

Within the walls of the National Museum of Natural History’s Discovery Room, volunteers interact with visitors as they examine fossils, skulls, shells and other objects from the museum’s collection. These volunteers have one of the most important jobs of all: inspiring scientific curiosity in Smithsonian visitors and honing the visitors’skills in observation and inquiry, giving them the tools they need to answer all their questions about the natural world.

Outside of Smithsonian Institution and Washington, D.C. there are an abundance of opportunities for citizen scientists to get their volunteer on. Behind-the-Scenes Volunteer Program’s Lemon says rough estimates indicate there are more than a million volunteers at America’s 17,000-plus museums.

Michael Gold and the rest of the staff at ScienceForCitizens.net have developed an entire online community for citizen scientists. The Web site allows those wishing to volunteer for science to connect with real volunteer projects and research opportunities in their area to match their interests.

Researchers at the University of Chicago have found that we judge non-native speakers to be less believable, though not because of any bias against foreigners. Instead, they say, it’s simply because we find these speakers harder to understand. (The study will appear in an upcoming issue of the Journal of Experimental Social Psychology.)

Students learning English in Korea (courtesy of flickr user blese)

Shiri Lev-Ari and Boaz Keysar recorded three native English speakers, three speakers with mild accents (Polish, Turkish and Austrian-German) and three with heavy accents (Korean, Turkish and Italian) repeating statements like “a giraffe can go without water longer than a camel can.” Speakers of American English then listened to 45 of these statements, 15 by each type of speaker. The listeners were told that the speakers were saying things that an experimenter had written, not expressing their own knowledge (in an attempt to rule out bias against the individual speaker), and asked whether each statement was true or false.

Statements read by people with accents—either mild or heavy—were less likely to be rated as true than those repeated by a native English speaker. When the exercise was repeated with the American English speakers being told that “the experiment is about the effect of the difficulty of understanding speakers’ speech on the likelihood that their statements would be believed,” thus warning them that an accent could affect credibility, the mildly accented speakers were rated just as truthful as the native speakers. Statements from individuals with heavy accents, though, were still more likely to be perceived as false.

The difference in credibility, Lev-Ari and Keysar say, occurs because an accent reduces something called “processing fluency.” Instead of simply recognizing that we’re having problems understanding the words, we interpret those words as being less believable. The researchers note:

These results have important implications for how people perceive non-native speakers of a language … Accent might reduce the credibility of non-native job seekers, eyewitnesses, reporters or news anchors. … Most likely, neither the native nor the non-native speakers are aware of this, making the difficulty of understanding accented speech an ever present reason for perceiving non-native speakers as less credible.

Perhaps this explains why I never believe the call center people from foreign lands when they tell me the cable guy is right around the corner and will be only a few minutes late.

Gombe chimps eating a red colobus monkey (courtesy of flickr user kibuyu)

1) Chimpanzees eat meat: Before Goodall began her studies in Gombe, most scientists thought that chimpanzees were vegetarians. That notion was quickly dropped after Goodall observed chimps eating what appeared to be a freshly killed piglet in October 1960. She would later observe chimps hunting young bush pigs and baby colobus monkeys.

2) Chimpanzees use tools: Goodall observed two chimps, David Greybeard and Goliath, using sticks to extract termites, the first instance of a non-human species using a tool. Gombe chimps also use sticks to catch army ants and use leaves to soak up water to drink and to clean themselves. Other chimps have been observed using stones to crack open nuts.

3) Chimpanzees engage in warfare: In 1974, the Gombe chimps split into two groups that then proceeded to battle for dominance for the next four years. This was the first instance of a non-human primate species engaging in long-term war.

4) Chimpanzees can be cannibals: In 1975, one female chimp, Passion, was observed killing another’s infant and sharing the meat with her daughter, Pom. The pair would continue their infant cannibalism for two years. A similar event has been observed among chimps in Uganda.

5) Chimpanzees have complex social relationships: Chimpanzees live in small groups of up to six individuals, and several of these smaller groups belong to a larger community of 40 to 60 chimps. The males, led by an alpha, dominate the group, while the females have their own hierarchy. Within those groups, there is a complex set of social interactions, a chimp “soap opera” almost, that has kept the Gombe researchers busy for the past five decades.

A rhinoceros drawn on the wall of a cave in Romania (Credit: Andrei Posmosanu/Romanian Federation of Speleology)

In modern times, rhinos are exotic creatures that inhabit faraway lands in Asia and Africa. There are only five living species; all but one is threatened with extinction. But rhinoceroses are an old lineage. They have been around for 50 million years or so, and they once roamed areas in North America and Europe, in temperate and even arctic regions (there was even a woolly rhino).

Some species in Europe survived past the end of the last Ice Age and didn’t become extinct until around 10,000 years ago. That made them perfect subjects for long ago cave artists, like the one who made the drawing above, which was found last year in a cave, Coliboaia, in northwestern Romania. Much of the cave is underwater, which explains why the drawings were only found recently though the cave itself was discovered 30 years ago. Spelunkers exploring the cave found about half a dozen images of animals, including two rhinos, a bison and a horse. There may have been other paintings but they were likely destroyed by the water that now fills the cave.

Jean Clottes, a cave art expert from France (where the most famous cave art can be found, in Lascaux), has estimated that the drawings are around 23,000 and 35,000 years old, based on their style and similarities to other prehistoric art. Radiocarbon dating of the drawings or nearby bear bones may provide a more accurate estimate of when these ancient artists lived.

Check out the entire collection of Surprising Science’s Pictures of the Week on our Facebook fan page.

Photo of Genyornis rock painting, courtesy Ben Gunn

A pair of giant, extinct birds depicted on a rock in Australia could be the continent’s oldest work of art.

When humans first set foot on Australia’s northern shores some 50,000 years ago, Genyornis newtoni, a bird three times the height of an emu, would have been an important item on their menu. This red ochre painting of the extinct bird—the first of its kind—was discovered in a narrow rock shelter in Arnhem Land two years ago, but its significance was recognized only this month after a visit by archaeologists.

“It means either that it was painted at the time of the Genyornis bird, or that the Genyornis had lived longer than we thought,” archaeologist Ben Gunn told the Agence France Press.

Some of the oldest rock paintings in the world are found in Australia, but putting a hard date on these ancient artworks remains a technical challenge. Scientists are rarely able to use chemical methods to estimate the ages of organic pigments, and must ballpark dates by judging the sophistication of the painting or its geological context. That’s why finding the depiction of an extinct animal is of such importance. Last year, for instance, scientists identified a marsupial lion painted on rocks in the Kimberley region, suggesting those paintings are at least 30,000 years old.

Genyornis is thought to have gone extinct relatively soon after humans arrived on the scene, which means the newly discovered painting could be 40,000 years old, making it the oldest in Australia, if not the world.

But, like most topics in the study of cave art, that interpretation has not been unanimous. Robert Bednarik of the International Federation of Rock Art Organizations told The Australian he was not convinced it depicted a Genyornis and he thought that it was only 5000 years old. “I am not aware of any painting or even petroglyph of an animal anywhere in the world that is more than 10,000 years old located outside of caves.”

Brendan Borrell will be guest blogging this month. He lives in New York and writes about science and the environment; for Smithsonian magazine and Smithsonian.com, he has covered the ecology of chili peppers, diamonds in Arkansas and the world’s most dangerous bird.

The bones of a Neanderthal toddler are displayed in the Hall of Human Origins at the National Museum of Natural History (photo by Sarah Zielinski)

It’s one of the great questions of human evolution: Did Homo sapiens interbreed with Homo neanderthalensis? The two species had many similarities: they lived in caves, used similar types of tools and hunted the same prey. And they lived in the same place for long periods of time, most notably in Europe from 45,000 to 30,000 years ago. But analysis of the Neanderthal’s mitochondrial DNA provided no evidence that they had interbred with modern humans

However, scientists now have a draft sequence of the Neanderthal genome (published today in Science), and comparing it with the genomes of modern-day humans shows that interbreeding must have happened and that there’s evidence of Neanderthal genes in some humans.

The Neanderthal and H. sapiens genomes are 99.84 percent identical, but there is variation in similarity depending on where a modern-day human is from. The researchers compared the Neanderthal genome to those of people from China, France, Papua New Guinea, southern Africa and West Africa and found that the Neanderthals were slightly more similar to non-Africans. Further analysis revealed that the non-Africans had a small number of Neanderthal genes.

How did those genes get there? A likely scenario may be “the movement of a few Neanderthals into a group of humans,” University of California at Berkeley population geneticist Montgomery Slatkin told Science. One potential time and place for such an event would have been Israel about 80,000 years ago, where the two species overlapped for about 10,000 years. Interbreeding would have been rare, the scientists say, but they do not yet know what would have been preventing it from occurring more frequently.

The researchers are using the new genome sequence to tease out the ways in which Neanderthals and H. sapiens are the same and the ways they are different (including differences in metabolism, skin, skeleton and the development of cognition) in the hopes of discovering what truly makes us human.

Inspired by this new research, I finally visited the new Hall of Human Origins at Smithsonian’s National Museum of Natural History this week (where I snapped the picture above, of the bones of a Neanderthal child). If you’re in the Washington, D.C. area, I recommend stopping by. I’ve read, and written, so much about human evolution, but seeing the evidence in person still brings surprises—I had no idea the hobbit people of Flores were so tiny or that hand axes were that hefty—that’s the sort of thing you just can’t realize from words and pictures alone.

The main plaza of Monte Albán in Mexico (Credit: Charles S. Spencer, AMNH, used with permission)

Bureaucrat is a dirty word to some people in modern society, so how can a bureaucracy be a good thing? Charles S. Spencer, an anthropologist at the American Museum of Natural History, argues this week in PNAS that bureaucracy was essential to the growth and expansion of the first states that formed across the globe, from Mexico to Egypt to China.

The evolution of a society into a state, according to modern anthropological theory, starts with an egalitarian society in which there are no permanent inequalities among social units—families, villages, etc.—and individuals become leaders through achievement, not birth. The next step is the chiefdom, or rank society, which is led by an individual of elite descent. Authority is centralized and the leader’s best strategy for management avoids delegation of authority. In pre-industrial times, this strategy would have limited the size of territory that could be controlled to about half a day’s travel by foot from the chief’s center of power, some 15 to 19 miles. The third step is a state, defined by the existence of a bureaucracy in which functions and authorities are delegated to specialists.

Anthropologists had thought that the territorial expansion of a state, sometimes called the “imperial” phase, occurs well after the state first appears. Spencer, however, argues that the two are linked and actually form a positive feedback loop:

Although the nascent state will be more expensive to sustain than the antecedent chiefdom, the new resources gained through successful territorial expansion will do much to defray the costs of the administrative transformation. The growth and proliferation of bureaucratic governance will continue as more and more resources are harnessed, leading to further delegation of authority, more territorial expansion, and still more resource extraction–a positive-feedback process that reinforces the rise of a state government qualitatively and quantitatively more complex and powerful than the chiefdom that preceded it.

If Spencer’s theory is true, then the appearance of bureaucracy (the formation of the state) and signs of its expansion should occur at nearly the same time in the archaeological record.

In his paper, Spencer focuses on a site called Monte Albán in Mexico’s Oaxaca Valley. Near the site, Spencer found a royal palace—evidence of a specialized ruling class—and a multi-room temple that indicated the existence of a specialized priestly class that date to the period of 300 to 100 B.C. It was at that same time that the Monte Albán began conquering peoples who lived outside the valley and more than a two-day round-trip from the state’s center. Archaeological evidence indicates that more powerful rivals to the south and east were able to resist the Monte Albán during the early years of expansion, but after the Monte Albán state grew even bigger, they too were conquered.

Spencer found similar evidence timing the rise of bureaucracies and the expansion of states when examining the archaeological record of the Moche state in Peru (c. 200 to 400 A.D.), the Hierakonpolis chiefdom of Egypt (3400 to 3200 B.C.), the Uruk state of Mesopotamia (3500 B.C.), Harappa in the Indus Valley of Pakistan (2600 to 2500 B.C.) and the Erlitou state of China (1800 to 1500 B.C.). In each case Spencer found that the development of bureaucracy was necessary for the development of the empire (even on a small, preindustrial scale).

We’ll have to leave the question of whether the empire is a good thing for another day.