Photo: muffet

Pregnancy tests did not always come in an easy-to-use, sterile kit that provided almost immediate results. Less than a century ago, women had to rely upon frogs instead. In 1938, Dr. Edward R. Elkan wrote in the British Medical Journal:

The discovery of what is now known as the xenopus pregnancy test is based on experiments conducted by Hogben (1930, 1931), who observed that hypophysectomy produced ovarian retrogression, and the injection of anterior pituitary extracts ovulation, in the female South African clawed toad.

The African clawed frog, as its better known today, was imported around the world for its use in pregnancy tests. Doctors would ship urine samples to frog labs, where technicians would inject female frogs with a bit of the urine into their hind leg. The animals would be placed back into their tanks, and in the morning the technicians would check for tell-tale frog eggs dotting the water. If the female frog had ovulated, that meant the woman who provided the urine was pregnant and the pregnancy hormone, human chorionic gonadotropin, had kicked off ovulation in the frog. Researchers referred to this procedure as the Hogben test.

Among the 295 tests which I have done so far and in which 2,112 frogs were used I have not seen one clear positive that did not indicate a pregnancy. There were a few negative results which when repeated after a fortnight became positive, but I do not think that these can be regarded as failures.

Frogs were actually a great improvement on the previous means of testing whether or not a woman was pregnant.   Welcome History describes:

Prior to Xenopus, female mice and rabbits had been used, but these had to be slaughtered, dissected and carefully examined for ovarian changes. Because toads were reusable and could be conveniently kept in aquaria, Xenopus made pregnancy testing practical on a larger scale than before.

Thousands of the frogs were exported across the world from the 1930s to 1950s for use as pregnancy testers.

Immunological test kits finally replaced Xenopus in the 1960s and were rapidly taken up by private companies and feminist organisations offering diagnostic services directly to women. The first over-the-counter home test was sold in pharmacies in the early 1970s, but it resembled a small chemistry set and so was not user-friendly. It was not until 1988 that the first recognisably ‘modern’ one-step-stick hit the shelves.

But the frogs’ legacy lives on. African clawed frogs can be found living around many urban centers today, where they were likely released into the wild after hospitals no longer had use for them. Additionally, the imported frogs are common pets, and no doubt some of those pets wear out their welcome and get chucked into a local stream or pond.

In 2006, researchers realized that the frog may be carriers for the deadly amphibian chytrid fungus, which has caused the extinction and decline of around 200 amphibian species around the world. Now, research published in PLoS One shows for the first time that populations of African clawed frogs living in California carry the fungus. The frogs can carry the disease for long periods without being affected themselves, so researchers suspect that they may be the original vectors that introduced the fungus around the world—a sort of revenge for being used as egg-laying research subjects for all those years.

More from Smithsonian.com:

Three New Frog Species Face an Uncertain Future  
Crayfish Have Been Secretly Spreading a Deadly Frog Epidemic 

Parasitic hookworms in a person’s intestinal lining. Photo: CDC Public Health Image Library

Of the neglected tropical diseases, parasitic worms, or helminths, are one of the most common maladies. Diseases like this, caused by parasite or bacteria, kill around 534,000 a year, according to the CDC.  These have been largely wiped out in developed countries, but they still persist in the poorest parts of the world. People pick up infections by walking or consuming bits of contaminated soil in areas where sanitation is poor. After a person becomes infected, he perpetuates the infection in others through feces teeming with worm eggs.

Treating the worms is usually straight forward, but doctors must first determine whether or not a person is infected. Microscopes are not always available in poor communities, however, since they are difficult to transport and break easily. To get around this, an international team of doctors have developed an impromptu microscope by sticking a cheap lens onto his iPhone using double-sided tape. The New York Times describes the contraption:

The invention, described recently in The American Journal of Tropical Medicine and Hygiene, was tested in Tanzania on 200 stool samples from children who had a mix of hookworms, roundworms and giant roundworms.

A three-millimeter ball lens was taped over the camera lens of an iPhone 4. The zoom was increased to maximum, and slides, with tape atop the samples, were pressed right up to the lens. A pen flashlight shone light through the slide.

The improvised microscope detected giant roundworm eggs 81 percent of the time, roundworm eggs 54 percent of the time and hookworm eggs 14 percent of the time. The latter parasite may evade detection because it produces fewer eggs which also tend to degrade quickly outside of the body, the Times writes.

In order for doctors to determine whether or not to treat a person or village with anti-helminth medication, they need to have a microscope that performs with at least 80 percent accuracy. Unfortunately, the iPhone scope delivered results at just 70 percent accuracy compared to a conventional microscope. But with increasingly high tech smartphone cameras frequently introduced, the Times points out, the iPhone may soon find its place as a diagnostic tool after all.

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Photo: jnissa

In Mozambique, it seems to be game over for rhinos. A wildlife warden in the Great Limpopo Transfrontier park—the only place where rhinos were still surviving in the southern African country—told AP that the last of the animals have been killed by poachers.

Elephants also could become extinct in Mozambique soon, the warden, Antonio Abacar, warns. He says game rangers have been aiding poachers, and 30 of the park’s 100 rangers will appear in court soon. “We caught some of them red-handed while directing poachers to a rhino area,” Abacar says.

In Asia, the hacked-off horns can fetch a price equivalent to more than their weight in gold. Traditional Chinese medicine holds that the ground horns have curative properties. (Science holds that they do not.) In China and Vietnam, the horns are also used as decorations or as aphrodisiacs.

Mozambique’s rhinos have been living on the edge of extinction for more than a century, when big game hunters first arrived and decimated populations. Conservationists there have painstakingly built the population up over the last few years, but poachers—who often have significantly more funding, manpower and resources than wildlife wardens—seem to have finally stamped out the country’s rhinos for good. Mozambique’s conservation director remains hopeful that a few stray rhinos may still exist, however.

For many wildlife wardens, the lure of money and the lack of legal deterrents, often proves too much to resist. AP describes the typical case:

A game ranger arrested for helping poachers in Mozambique’s northern Niassa Game Reserve said on Mozambican Television TVM last week that he was paid about $80 to direct poachers to areas with elephants and rhinos. Game rangers are paid between $64 and $96 a month, and though the guilty ones will lose their jobs, the courts serve as little deterrent to the poachers: Killing wildlife and trading in illegal rhino horn and elephant tusks are only misdemeanors in Mozambique.

According to the Wall Street Journal, Mozambique’s government is still working on legislation first drafted in 2009  which would impose mandatory prison sentences for people caught shooting wildlife.

More from Smithsonian.com:

Wildlife Managers Are Poisoning Rhino Horns to Stop People From Eating Them 
In Vietnam, Rhino Horn Is the Drug of Choice at Both Parties and Hospitals 

In places where malaria thrives, mosquito nets are used to keep the bugs away from people as they sleep. Photo: Matt Handy

In 2010 alone, malaria infected 219 million people, largely in tropical regions in Africa, South and Central America, Asia and the Philippines. That year, the disease, caused by a parasite carried by mosquitos, killed 660,000 people. Objectively, that’s a high number of deaths, but compared to the number of infections, it’s relatively low. Right now, powerful anti-malarial medication protects those millions of infected people. But, says the BBC, a new strain of the parasite has been found in Cambodia that resists the leading class of anti-malarial drugs.

The new strain, first identified in 2008, is resistant to artemisinin, a “frontline drug in the fight against malaria,” the BBC writes. Since it was first discovered, the resistant version of malaria has spread around Southeast Asia. Health organizations are working hard to contain the spread of the drug-resistant variety: if the drugs are rendered ineffective, the consequences could be dire for millions of people.

This isn’t the first anti-malarial to be rendered useless, either. “The history of antimalarial medicine,” says the Mayo Clinic, “has been marked by a constant struggle between evolving drug-resistant parasites and the search for new drug formulations.”

Modern political history is already intertwined with the history of anti-malarial medications, and if drug-resistant strains of malaria continue to spread, they could prompt far-reaching changes. The advent of the first anti-malarial, says Glencoe World History, enabled European imperialism into tropical regions worldwide.

“Before 1850, the fear of disease was a major factor in keeping Europeans from moving into Africa. Especially frightening was malaria, an often fatal disease spread by parasites. …By 1850, European doctors had learned how to treat malaria with quinine, a drug that greatly reduced the death rate from the disease. Quinine is a bitter drug obtained from the bark of the cinchona tree, which is native to the slopes of the Andes in South America.”

Malaria is most common in tropical and sub-tropical regions where the mosquitos that carry the parasite live. Photo: CDC

Cinchona trees were transplanted from South America to India, and a steady supply of the drug enabled Europeans to move across Africa.

“By the beginning of the twentieth century, more than 90 percent of African lands were under the control of the European powers. A drug found in the bark of Latin American trees, which were then grown in Asia, had been used by Europeans to make possible their conquest of Africa.”

Since then, multiple generations of anti-malarial medication have come and gone (and researchers are still announcing promising new leads). But any time a drug-resistant strain like the one in Cambodia develops, it’s worth keeping an eye on.

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Photo: Kevin H.

In South Africa, lion bones are selling for around $165 per kilo (2.2 pounds). That’s about $5,000 for a full skeleton. The skull is worth another $1,100, according to the Guardian.

Over the past several months, officials in South Africa have noticed a steady increase in the number of permits they’re issuing for export of lion bones from certified trophy dealers. Such establishments breed lions for the express purpose of allowing wealthy tourists to engage in a controlled lion hunt. After killing the animal, if the patron does not want its body or bones, the breeders can then turn a large profit by stripping the lion down and selling its parts to Chinese and Southeast Asian dealers. The Guardian explains:

In 2012 more than 600 lions were killed by trophy hunters. The most recent official figures date from 2009, certifying export of 92 carcasses to Laos and Vietnam. At about that time breeders started digging up the lion bones they had buried here and there, for lack of an outlet.

In China, Vietnam and some other Southeast Asian nations, lion bones serve as a stand-in for tiger bones. Practitioners of traditional Chinese medicine believe the bones help with allergies, cramps, ulcers, stomach aches, malaria and a host of other ailments. As with many other purported traditional Chinese medicine “cures,” tiger bones ground into a powder and mixed with wind is also said to boost a man’s sexual prowess.

Despite the lack of scientific proof this potion is very popular, so with tiger bones increasingly scarce, vendors are replacing them with the remains of lions. Traders soon realised that South Africa could be a promising source. It is home to 4,000 to 5,000 captive lions, with a further 2,000 roaming freely in protected reserves such as the Kruger national park. Furthermore such trade is perfectly legal.

But just because trade in legally-sourced lion bones is given the green light from the South African government does not mean illicit activities are not underway. One investigator told the Guardian that he estimates that the legal market only contributes half of the lion bones currently leaving the country. That means poaching is responsible for the rest.

More from Smithsonian.com:

State Department Takes on Illegal Wildlife Trade 
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An A. sediba skull. Photo: Brett Eloff

Around 2 million years ago, the first humans evolved from australopiths, our smaller-brained ape-like ancestors. Back in 2008, researchers found two skeletons in South Africa from the ape-like Australopithecus sediba. A male and female skeleton, called MH1 and MH2, were buried together, and further excavations revealed an infant and another partial adult skeleton nearby. All of the remains dated back to around 1.8 to 1.9 million years old. These skeletons began to raise questions about what we really know about human evolution and Homo origins.

The researchers published their results in the journal Science in 2010, writing:

Despite a rich African Plio-Pleistocene hominin fossil record, the ancestry of Homo and its relation to earlier australopithecines remain unresolved. Here we report on two partial skeletons with an age of 1.95 to 1.78 million years. The fossils were encased in cave deposits at the Malapa site in South Africa. The skeletons were found close together and are directly associated with craniodental remains. Together they represent a new species of Australopithecus that is probably descended from Australopithecus africanus. Combined craniodental and postcranial evidence demonstrates that this new species shares more derived features with early Homo than any other australopith species and thus might help reveal the ancestor of that genus.

Until this discovery, researchers had assumed that Lucy, the remains, more than 3 million years old, of an Australopithecus afarensis female found in 1974, represented either our direct evolutionary ancestor or else a very close ancestor. But Lucy’s skeleton was found in Ethiopia, about 4,000 miles away from the A. sediba remains uncovered in South Africa. 

Immediately,  i09 explains, researchers began to second guess whether Homo emerged from East Africa after all. Our origins instead may be more southerly. Now, a new slew of studies published by the same research team in Science answers some questions about what our ancestor was like while also opening up some new mysteries. The New Scientist gives a run down of the “bizarre mosaic” of qualities resembling both Homo and Australopithecus africanus (another South African species that lived around 2 to 3 million years ago) that a closer examination of the A. sediba specimens revealed.

The Homo-like traits included:

• Same number of vertebrae
• Human-like waist
• Bottom of the ribcage narrows
• Walked upright
• Small canine teeth.

And the ape-like traits were:

• Top of the ribcage tapered towards the shoulders, preventing the arms from swinging when walking  
• Arms and legs appear well equipped to swing and balance on branches
• When walking, rather than planting its heel first like Homo, A. sediba’s gait was more twisty and hoppy thanks to a flexible midfoot.

Where A. sediba fits into the evolutionary tree is still under debate. Based upon studied of the specimens’ teeth, it does not appear that A. sediba evolved from A. afarensis (Lucy) in East Africa. Instead, the New Scientist writes, A. africanus seems to be the most likely ancestral candidate.

That suggests the roots of both lineages of australopiths – from East and South Africa – are even older. “It appears that there may be a ‘ghost lineage’ of unrecognised hominins that goes back deeper in time than afarensis,” says Lee Berger at the University of Witwatersrand in Johannesburg, South Africa, who discovered A. sediba.

National Geographic points out that the questions surrounding A. sediba, such as why it seemed to return to the trees after it first evolved to walk on the ground and where it fits in on the human evolution puzzle, are far from resolved.

Are the ways that Australopithecus sediba resembles early Homo species true indicators of a close evolutionary relationship—or are they traits that evolved independently in both lineages?

Few scientists believe this question has even begun to be settled.

But A. sediba will likely leave a significant mark on science, in any case:

Regardless of what Australopithecus sediba turns out to be, however, the fossils offer an important caution about interpreting more fragmentary human remains found elsewhere.

The hominin “is so curious in its totality,” [paleoanthropologist Rick] Potts says, “it might lead to some rethinking of how we classify fossil humans and place them in our evolutionary tree.”

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Image: Clem Evans

In South Africa, one recent robbery broke the blast-open-the-safe, steal-the-gold mold of bank heists. The thieves did break into a safe and steal millions of dollars worth of loot. But they didn’t make off with gold or Picassos. They stole rhino horns—nearly $3 million worth.

The safe contained 66 southern white rhino horns, removed from the animals on the Leshoka Thabang Game Reserve to protect them from poachers who often kill the giant beasts just for their horns. The thieves apparently broke into the reserve’s office and used a blowtorch to open this safe and snag the horns.

Demand for rhino horns, which go into traditional medicine cures for everything from cancer to hangovers, is growing, and right now the going rate (just about $30,000 a pound) is higher than gold’s.

Reuters called Johan van Zyl, the farmer whose safe contained the 66 rhino horns, which weighed almost 100 pounds in total. “In my hands it is worth nothing, but in the hands of the guys who have it now, the horns are worth a lot of money,” he told them.

Part of what’s driving the price up is that rhinos are getting rarer, because they’re being poached so much. The Western Black rhino was poached to extinction just this year. Reuters estimates that last year poachers killed 660 rhinos in South Africa. This year that number could jump to 800. And 75 percent of the rhinos in the world live in South Africa.

To save the dwindling rhino population, some rangers are taking the drastic measure of poisoning rhinos’ horns to deter people from eating them.

And it isn’t only rhinos in the wild which are being attacked for their horns. In July of last year, two men cokes into the Ipswitch Musuem and ripped the horn off a museum specimen. This museum heist wasn’t an isolated event either. Here’s the Guardian:

According to the Metropolitan police, 20 thefts have taken place across Europe in the past six months – in Portugal, France, Germany, the Czech Republic, Belgium and Sweden as well as the UK. Scotland Yard and Europol are now advising galleries and collectors to consider locking up their rhino horn collections or keeping them away from public view. Several institutions, including the Natural History Museum and theHorniman Museum in south London, have removed their displays or replaced horns with replicas.

Law enforcement officials think that these museum heists were all carried out by the same team of criminals, hungry for horns—although most likely the South African safe heist wasn’t related. The Convention on International Trade in Endangered Species (CITES) called the rhino hunting situation “bleak” in 2009, and it’s only gotten worse. Until rhino horns stop being worth more than gold, it’s unlikely that the giant beasts, or their horns, will be safe anywhere.

More from Smithsonian.com:

Wildlife Managers Are Poisoning Rhino Horns to Stop People From Eating Them
Defending the Rhino

Photo: World Resources

In South Africa, the Guardian reports, some wildlife managers are attempting a radical new method of combating the illegal wildlife trade. They are injecting live rhino’s horn with poison that would make people who consume it “seriously ill.”

Rhino horns currently fetch the equivalent price or more of their weight in gold in markets in China and Vietnam, where they are largely used in traditional Chinese medicine concoctions or as a condiment to sprinkle atop dishes. Poaching and selling rhino horns is illegal, however, and taking the horns means killing the animals. So far this year, more than 200 rhinos have been poached in South Africa alone, meaning the country is well on its way to beating last year’s 668 total animals killed for their horns. Conservationists estimate that, at this rate, around 1,000 rhinos will die this year. 

The poison, a mix of parasiticides and pink dye, now fills more than 100 rhinos’ horns, which were not harmed in the process. Anyone who eats horns laced with the poison will become ill, with symptoms including nausea, stomach ache and diarrhea  though they will not die, managers say. Conservationists hope the poison—which is easily seen thanks to the pink dye—make consumers think twice before eating the purported “medicinal product.” Airport scanners can also detect the dye, whether it’s contained within a whole horn or ground into a powder. 

The chemicals are available over the counter, mostly used for controlling ticks on livestock, and injecting the horns with the poison is legal. Additionally, wildlife managers are warning would-be poachers and consumers with a media campaign and also by posting noticed on fences surrounding protected areas.

Some conservationists worry, however, that the poison will just encourage the poachers to seek rhinos in other parts of South Africa or Africa, or that poachers will even use their own dye to return the pink horns to their original color so they can still sell them to naive consumers.

More from Smithsonian.com:

Defending the Rhino 
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Photo: entendered

Thieves are plundering Europe’s museums of their rhino horns and elephant tusks. First it was Haslemere Educational Museum and Norwich Castle Museum in England, then the Florence Museum of Natural History. Overall, the Guardian reports, more than twenty museums and auction houses in Britain, Germany, Sweden, Italy and Belgium have lost tusks and horns to poachers looking to turn a quick profit. Last weekend, Paris’ Museum of Natural History came close to becoming the latest member to join this growing list. The Guardian reports: 

Police were called to the museum in the early hours of Saturday morning where they found a chainsaw still whirring after a man in his 20s escaped over a wall with a tusk over his shoulder.

The thief, startled by the museum’s alarm system, tried to make a quick break for it but wound up fracturing his ankle.

The elephant in question once belonged to King Louis XIV. The animal was a gift from the Portuguese king in 1668 and was much beloved by Louis XIV and his visitors.

It lived for 13 years in the royal menagerie in the grounds of the opulent palace of Versailles where it became the star attraction. When it died, its skeleton was transferred to the natural history collection in Paris, one of the biggest in the world alongside London’s Natural History Museum.

The tusks, in fact, were added to the skeleton in the 19th century. The wildlife black market isn’t paying for historical value, though; buyers are purportedly interested in the value of animal parts in traditional Chinese medicinal. Elephant tusks currently fetch hundreds of dollars per pound while rhino horns go for much higher prices.

The Parisien museum curators say they’ll restore the sawed off horn to its rightful place. Curators at other institutions, such as London’s Natural History Museum, are not taking any chances, however. They replaced their horns two years ago with fakes.

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Photo: Kyle Rush

The famous story of Cleopatra’s suicide gets points for drama and crowd appeal: Her lover, Mark Antony, had been defeated in battle by Octavian and, hearing that Cleopatra had been killed, had stabbed himself in the stomach. Very much alive, after witnessing his death, the beautiful last Pharaoh of Ancient Egypt pressed a deadly asp to her breast, taking her own life as well.

But what if Cleopatra didn’t commit suicide at all?

Pat Brown, author of the new book, The Murder of Cleopatra: History’s Greatest Cold Case, argues that the “Queen of Kings” did not take her own life. Rather, she was murdered, and her perpetrators managed to spin a story that has endured for more than 2,000 years.

Brown, writing for The Scientist, says she decided to treat Cleopatra’s story as any typical crime scene.

I was shocked at the number of red flags that popped up from the pages of the historical accounts of the Egyptian queen’s final day. How was it that Cleopatra managed to smuggle a cobra into the tomb in a basket of figs? Why would the guards allow this food in and why would they be so careless in examining them? Why would Octavian, supposedly so adamant about taking Cleopatra to Rome for his triumph, be so lax about her imprisonment? Why would Cleopatra think it easier to hide a writhing snake in a basket of figs rather than slip poison inside one of the many figs? How did all three women end up dead from the venom? Wasn’t it unlikely that the snake cooper­ated in striking all three, releasing sufficient venom to kill each of them? Why was the snake no longer present at the crime scene? Was a brand-new tomb so poorly built that holes remained in the walls of the building? Why did the guards not look for the snake once they thought it had killed the women? Why were the wounds from the fangs of the snake not obvious? Why did the women not exhibit the symptoms of death by snake venom or even by poison? Why did the guards not see any of the women convulsing, vomiting, or holding their abdomens in agony? Why didn’t they see any swelling or paral­ysis of face or limbs or any foaming at the mouth?

Brown began pursuing these answers through historical texts and more recent scholarly works. She spoke with Egyptologists, poison experts, archeologists and historians of the ancient world, slowly forming her own version of what really took place August 12, 30 BC.

With each step back in time from the end of Cleopatra’s life to the beginning, I discovered more and more evidence pointing to a radically different explanation of history than the ancients and Octavian wanted us to believe.

In this story, Cleopatra never loved Antony or Julius Caesar. Antony was murdered, and Cleopatra was tortured and strangled to death.

I believed Cleopatra may have been one of the most brilliant, cold-blooded, iron-willed rulers in history and the truth about what really happened was hidden behind a veil of propaganda and lies set in motion by her murderer, Octavian, and the agenda of the Roman Empire.

This book, Brown hopes, will set the record straight.

*This post has been updated.

More from Smithsonian.com:

Who Was Cleopatra? 
Rehabilitating Cleopatra 

Starting a few hundred million years after the universe expanded from an infinitesimally dense point, on and on through the formation of the Earth 4.6 billion years ago to the development of life, agriculture, civilization, and war, this dramatic video tracks the rise of America and sets out to encompass the span of human origins in just two minutes.

As YouTube commenters point out, as a representation of the chronological scale of the universe, the video is a bit skewed, with the formation of the Earth coming at the six second mark and the 20th century filling the bulk of the story. But as a story of humanity, the video, made by Minnesota high school student Joe Bush, highlights many of the important events, debates and developments of human history: the rise of agriculture in the Fertile Crescent, the expansion of Asian, European and African civilizations, the Renaissance, the civil rights movement, and more. (There is a lot missing, and a big emphasis on video games and conflict, but I’d suspect any high school history teacher would be proud of the breadth of topics presented.)

Bush’s video, titled “Our Story In 2 Minutes,” was made for a unique class at Stillwater Area High School in Stillwater, Minnesota. Known as Cutaway Productions, the class gives high school students a chance to run a video production company, making public service videos, music videos, advertisements and more.

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The ancient Chinese coin uncovered in Kenya. Photo: John Weinstein/The Field Museum

The 600-year-old coin is made of copper and silver and has a hole in the center. It’s called a Yongle Tongbao and was issued by Emperor Yongle, who reigned during the Ming Dynasty between the years 1403 to 1425 AD. It was found on Manda, an island in Kenya, announced researchers from The Field Museum and the University of Illinois, and it’s a tangible piece of evidence of Chinese exploration and trade in Africa, years before European explorers reached this part of the world.

It’s easy to date the coin: it features the emperor’s name. Yongle was perhaps best know for starting the initial construction of Beijing’s Forbidden City, but he also sent huge fleets of ships, under the command of admiral Zheng He, out across the ocean to faraway lands.

UCLA‘s International Institute explains:

Upon the orders of the emperor Yongle and his successor, Xuande, Zheng He commanded seven expeditions, the first in the year 1405 and the last in 1430, which sailed from China to the west, reaching as far as the Cape of Good Hope. The object of the voyages was to display the glory and might of the Chinese Ming dynasty and to collect tribute from the “barbarians from beyond the seas.” Merchants also accompanied Zheng’s voyages, Wu explained, bringing with them silks and porcelain to trade for foreign luxuries such as spices and jewels and tropical woods.

The researchers who found the coin describe Zheng He as “the Christopher Columbus of China.” But this admiral’s fleet was much larger than Columbus’. Zheng He commanded as many as 317 ships with 28,000 crew members; Columbus had just three ships and fewer than 100 crew to command.

The Chinese expeditions started out closer to home, but a voyage that began in 1417 made it to Africa. The fleet’s treasure ships brought back strange animals—giraffes, zebras, and ostriches—to the court at home.

After Yongle’s death, though, successors soon banned foreign expeditions and destroyed much of the documentation of the Zheng He’s voyages. The coin provides one of the few tangible links between Africa and China at that time. As for Manda, where the coin was discovered, that island was home to an advanced civilization for around 1,200 years, but it was abandoned in 1430 AD, never to be inhabited again.

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Image: USDA

In Australia, they’ve got a giant snail problem. The giant African snail is a true nightmare. These snails grow to the size of a baseball, can lay 1,200 eggs every year, survive all sorts of extreme temperatures, have no natural predators, and eat 500 crops, plus the sides of houses. Also, they carry meningitis that can infect and kill humans. Somewhat understandably, Australia isn’t pleased with any of this. So when one of these snails showed up in a shipping container yard in Brisbane, it was seized by Australian officials and destroyed, as quickly as possible.

The last time Australia dealt with the snail was in 1977, when they spent eight months hunting the invaders and exterminated 300 of them. Florida has dealt with the snail in the past too, spending a million dollars in 1975 to get rid of the snail that they estimated cost $11 million in damages each year. And last year, they were back in Miami. ABC News reports:

Officials realized they had a problem on their hands last week when two sisters flagged down a fruit fly inspector performing a routine check.

“A homeowner came out and said, I found these snails in my yard and she had one of them.  He recognized it as potentially being a giant African land snail,” Feiber said.

Officials have been focusing on the one square mile area around the home in southwest Miami. They are only 30 to 40 percent done with their investigation and have already found 1,100 snails.

These snails were so bad that NPR actually ran a story with the headline: “Miami Invaded By Giant, House-Eating Snails.”

The Department of Agriculture, Fisheries and Forestry of Australia has this to say about the snails:

Giant African snail originated in East Africa and is now present on most Pacific and Indian Ocean islands. The species was first recorded in American Samoa in the mid-1970s: a million snails were collected by hand in 1977 during a government campaign to reduce snail numbers, and more than 26 million snails were collected over the following three years.

The snails can come from all over. They might hitch a ride on a shipping container. Humans sometimes ship them in intentionally: In Miami, officials think an earlier snail outbreak might have come from a man practicing the African religion If a Orisha. In 1965, a child brought some snails back from Hawaii in his pocket, costing the city a million dollars and ten years of work.

All this makes it a little more understandable why Australia has spent so much energy killing this one individual snail.

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A black fly, the vector for river blindness, with a parasitic larvae emerging from the fly’s antenna. Photo: US Department of Agriculture

River blindness, one of the world’s leading causes of blindness, begins when a small parasitic worm wiggles its way into human skin. Tracking down this parasite once it’s entered a human body is challenging. But now scientists have developed a novel, easy-to-perform test that uses a molecule found in urine to issue a diagnosis, ScienceNOW reports.

After a parasitic worm first makes it under a person’s skin, it grows into an adult and releases eggs. These eggs move through the host’s bloodstream, and if the larvae happen to wind up in a person’s eye—and this happens quite often—he or she will likely go blind. An estimated 500,000 people in sub-Saharan Africa have lost their sight this way, ScienceNOW writes.

A variety of medications are available to kill the parasites, some more effective than others. But most treatments rely upon multiple doses over time to make sure a person’s system is completely purged of worms. Figuring out whether or not a person truly is free from the pests is key to knowing when to bombard their system with anti-parasite medications and when to stop.

Currently, to see if someone is infected, doctors perform a “skin snip,” cutting off a small piece of the patient’s skin and checking for worms inside. It’s not the most effective method. Researchers from Imperial College London hope to improve detection with a new method they just presented in the Proceedings of the National Academy of Sciences. ScienceNow describes the finding:

They compared the amounts of hundreds of molecules found in urine samples of infected and healthy Africans and discovered one striking difference: An unknown molecule was present at levels six times higher in the urine samples of infected individuals than in samples from healthy people. The researchers identified the molecule as the remnant of a neurotransmitter that larval stages of the worm excrete and that is then broken down in the human body before being excreted in the urine.

The test could be ready in three years, the team says.

More from Smithsonian.com:

The Parasite that Makes a Rat Love a Cat 
Blood-Eating Parasite Named for Late Reggae Artist Bob Marley 

Photo: Merseyside IT

Dominant female meerkats are bossy little animals. They fight their way to the head of the pack, slap the other females around—especially when they’re pregnant—and assume a position at the front of the line when the group moves around. When things get hairy, however, dominant females are more than happy to let their subordinantes assume the risk. New research shows that animals lower on the totem pole are forced to cross busy roads first while the leader assesses the danger from safety, Conservation Magazine reports.

In this new study, researchers wanted to know how meerkats in South Africa respond to human-imposed threats, like roads. They observed four groups of animals during 52 different crossings. The dominant female led the group half of the time, but after reaching the road she usually dropped back and allowed another meerkat to cross first. When dominant females were in the lead, they led the group across the road only 41 percent of the time, whereas when subordinates were in the lead from the beginning, they continued across the road 84 percent of the time.

The dominant female is obviously watching her own back, but the authors point out that this behavior also may help the group as a whole. Dominant females, in addition to pushing the smaller and younger girls around, act to hold the group together as leaders and also bear the brunt of reproduction.

More from Smithsonian.com:

Meerkats and Ground Squirrels Live Together, Respond to Threats Differently 
Wild Things: Life as We Know It