Pictures: New Dinosaur, Crocodile Cousin Found in Brazil

The nearly complete skull of a new species of ancient crocodile cousin has been found inBrazil, paleontologists say.

The animal is what's called a crocodyliform, part of a group known as the crocodilians that includes modern-day alligators, caimans, and more. (Seealligator and crocodile pictures.)

DubbedPepesuchus deiseae, the new species lived between 99 million to 65 million years ago during the lateCretaceous period.Brazilian National Museumpaleontologists recently found a skull and jawbone of the crocodile cousin at a fossil site in São Paulo state.

Seen above during a March 16 presentation, the fossil skull is"in incredibly good condition,"said team leader Alexander Kellner."We had enough basis to build a fairly good replica, showing what it probably looked like in real life."

(Relatedpictures:"5 'Oddball' Crocs Discovered, Including Dinosaur-Eater.")

The new crocodile cousin and another newfound species—a meat-eating dinosaur that's the biggest of its kind yet found in Brazil—were described recently in theAnnals of the Brazilian Academy of Sciences. The fossils are now housed at the Federal University of Rio de Janeiro's National Museum.

—Sabrina Valle in Rio de Janeiro, Brazil

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Pictures: New Ruby-Eyed Pit Viper Discovered

Seen coiled around a branch in an undated picture, a new species of snake called the ruby-eyed green pit viper (Cryptelytrops rubeus) has been discovered in Southeast Asia, according to a recent study. The snake lives in forests near Ho Chi Minh City and across the low hills of southernVietnamand easternCambodia's Langbian Plateau.

Scientists collected green pit vipers from Thailand, Laos, Vietnam, and Cambodia between 1999 and 2003 and examined them in the lab, using physical characteristics and genetics to identify new species.

"We know this species from only a few specimens, and very few people in the world have seen this snake,"said study co-authorAnita Malhotra, a molecular ecologist at Bangor University in the U.K."We know very little about what it does, to be honest."

Malhotra and colleagues also discovered a very similar species with striking yellow eyes (not pictured) dubbed the Cardamom Mountains green pit viper (Cryptelytrops cardamomensis), which inhabits southeastern Thailand and southwestern Cambodia. Both new species were described in theJanuary 23 issue of the journal Zootaxa.

—Brian Handwerk

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Pictures: Rare Penguins Blackened by Remote Oil Spill

Oil patches cover a northernrockhopper penguinon March 23, a week after a cargo vessel slammed into Nightingale Island in the South Atlantic, initiating a roughly 1,500-ton of fuel-oil spill, according to the U.K.-basedRoyal Society for the Protection of Birds.

The island, part of the British territory ofTristan da Cunha (see map), is home to 200,000 northern rockhopper penguins, half the world's population. TheInternational Union for Conservation of Naturelists the bird as endangered, due to its mysteriously rapid decline in the past three decades.

Oil-Spill Video: Nightingale Island Wildlife

On March 18, two days after it had run aground, theMalta-registered"M.S. Oliva broke her back in the force of a relentless swell,"leaking oil that spread into an 8-mile (13-kilometer) slick, according to the bird-protection group and theTristan da Cunha government's website. However the slick seemed to have mostly dissipated by March 23.

Some 65,300 tons of unprocessed soybeans also spilled from into the ocean, and the vegetables' impact to the sensitive marine environment are unknown, the government's website said.

Hundreds of oiled birds are washing ashore, and a preliminary estimate suggests up to 20,000 birds may have been affected, according to the government's website.

(See pictures of birds oiled by the 2010 Gulf of Mexico oil spill.)

"The scene at Nightingale is dreadful,"Trevor Glass, the conservation officer for the territory, said in a statement.

The"grave environmental disaster"may also reach ecosystems of the nearby Inaccessible and Gough islands, both UNWorld Heritagesites, according to the government's website.

—Christine Dell'Amore

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Odd Saber-Toothed Beast Discovered—Preyed on ... Plants?

Thriving long before thedinosaurage,Tiarajudens eccentricuswas armed with an incredible arsenal of teeth for grinding, tearing, and even scaring. But the newly discovered saber-toothedmammalancestor was a vegetarian, a new study says.

Not only did the big-dog-sizeanimal have huge canines—each as large as a crayon—but the roof of the animal's mouth appears to have been studded with teeth, which allowed for rapid replacement of lost teeth, as in sharks, researchers say.

Part of the Anomodontia suborder within the Therapsida order—often called mammal-likereptiles—the 260-million-year-old fossil vegetarian"looks like a combination of different animals, and it takes some time to believe it when you see this animal in front of you,"said paleontologistJuan Carlos Cisneros, who discovered the fossil inBrazil.

"It has the incisors of a horse, which are very good for cutting and pulling plants; the big molars of acapybara (picture), for grinding; and the canines of a saber-toothed cat."

(Related:"'Social' Sabertooths Hunted in Packs, Study Says.")

Paleontologist Jörg Fröbisch said the saber teeth are a particular surprise, considering the animal's diet of fibrous plants.

"You would usually expect saber teeth in a carnivore,"said Fröbisch, of theHumboldt University of Berlin.

"The best known animals are obviously saber-toothed cats or tigers, but there are also some {extinct} forms known among the marsupials, relatives of kangaroos and wombats,"added Fröbisch, who wasn't involved in theTiarajudens eccentricusstudy, to be published tomorrow in the journalScience.

T. eccentricus'saber teeth might have deterred predators or intimidated or wounded rivals of the same species, the study authors speculate.

"Saber teeth used for display or fighting between members of the same species is something that we thought appeared in herbivores less than 60 million years ago,"said study leader Cisneros, of Brazil's Federal University of Piauí.

"IfTiarajudens eccentricus{used them this way}, then it appeared much earlier, when terrestrial communities were ... dominated by herbivores."

(Also see"Sabertooth Cousin Found in Venezuela Tar Pit—A First.")

Tooth Trials: Secret of Evolutionary Success?

Why did plant-eatingTiarajudens eccentricus—"the eccentric tooth of the Tiarajú region"—have idiosyncratic dentition? The answer may lie in evolutionary experimentation.

(Also see: the first knownvegetarian spideranddinosaur evidence of a shift to a vegetarian diet.)

No matter how unusual,Tiarajudens eccentricus'wildly differing teeth fit closely together during a bite—the better to grind up and process fibrous leaves and stems. This early example of a tight tooth fit in a therapsid may offer insights into why humans and other mammals are so equipped today, since mammals evolved from therapsids.

"This animal was already capable of eating like a modern ruminant, and that's very interesting,"Cisneros said. Ruminants are animals such as cows and goats, which chew their cud and have complex, multichambered stomachs.

These unique dental adaptations may also offer some clues to the striking success of the anomodonts during the middle Permian era, before dinosaurs dominated Earth. (Seea prehistoric time line.)

"Anomodonts were the most successful group of terrestrial vertebrates, with the most species, most diverse morphologies, and most ecological adaptations during this time,"the University of Humboldt's Fröbisch said.

"There were burrowing forms, climbing forms, semiaquatic forms, small rat-sized animals, and large cow-sized animals in this same group, and this is unique in the ancestral lineage of mammals,"he said.

"This early experimentation in different teeth, I'm sure, is part of why this group became so successful."

More: Saber-Toothed Cat Had Weak Bite, Digital Model Says>>

forNational Geographic News

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Why Transylvanian Chickens Have Naked Necks

Scientists have cracked why the Transylvanian naked neck chicken has a featherless neck—and it isn't to give vampires easier access.

The Transylvanianbird's naked neck results from a random genetic mutation that causes the overproduction of a feather-blocking molecule called BMP12, a new DNA study shows. (Get the basics on genetics.)

The mutation first arose in domestic chickens in northernRomaniahundreds of years ago. The naked neck chicken—also dubbed the churkey or turken—has a chicken-like body but a turkey-like head atop a long, deep-red neck.

Surprisingly, when scientists treated standard-breed chicken embryos with BMP12 in the lab, the young chickens developed no feathers on their necks—suggesting the neck is more sensitive to the molecule, according to study leaderDenis Headon, a developmental biologist at the University of Edinburgh's Roslin Institute.

To find out why, Headon and his team did a further DNA analysis, which revealed an acid derived from Vitamin A is produced on the naked neck's neck skin. The acid essentially enhances the BMP molecule's effects, making the birds' necks bare, they found.

(See"Half-Male, Half-Female Chicken Mystery Solved.")

Naked-Necked Birds Can Handle the Heat

Unlike most genetic mutations, which are generally bad for an animal, the naked-neck tweak has increased naked necks' popularity worldwide.

That's because bare-necked birds are more resistant to heat and thus produce better meat and eggs—especially crucial for poultry producers in hot climates such asMexico's, Headon said.

And naked necks aren't alone:"We think all birds have this priming or readiness to lose neck feathers first,"he noted.

"Once you have a mutation that increases BMP12 in skin, the neck is the region that's ready to lose its feathers—it's already more sensitive."

In the wild, for instance, it's likely thatostrichesand storks have lost their neck feathers to stay cool, though it's unclear whether BMP12 played any role. (See National Geographic's collection of bird pictures.)

"Evolution has always found it easy to lose neck feathers whenever it gets hot and the bird gets big."

National Geographic News

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Why Human Penises Lost Their Spines

Men have lost the DNA code that once made human penises spiny, according to a new analysis of thehuman genome.

Penile spines, which are still present in several modern animals, are usually small barbs of keratin—a type of hard tissue—that line the outside of the organ.

The prehistoric male enhancement existed in the common ancestor ofchimpanzeesand humans, which lived about six million years ago, according to the gene analysis.

But the"penile spine enhancer"code disappeared from human genes before our common ancestor split into modern humans and Neanderthals about 700,000 years ago, said study co-authorGill Bejerano, a developmental biologist at Stanford University in California.

(Seepictures:"'Torture' Phalluses Give Beetles Breeding Boost.")

In total, the scientists found at least 510 DNA"deletions"that have occurred during human evolution by comparing the human genome with those of a range of modern and extinct species—including chimps and Neanderthals.

These deletions have brought about various changes to our bodies, for instance, boosting ourbrainsizes and stripping our faces of sensory whiskers. (Explore an interactive of the human body.)

In addition to the penile spines,"we think there are probably 500 fascinating other stories out there—that's part of the excitement of this paper,"Bejerano said.

DNA"Switches"Can Have Big Effects

The DNA deletions—actually the result of rare cell mutations—do not hinder the overall function of a gene, the study authors noted. (Get a genetics overview.)

"Think about it as a lightbulb that's controlled by lots of different switches,"said study co-authorDavid Kingsley, also of Stanford.

"If you smash the lightbulb, the lights go out,"he said. But"if you just remove an individual switch, {you've} altered the response to one particular input. That may produce a big effect for that little circuit, but it still preserves lots of other things."

Co-author Bejerano emphasized that one of the paper's key messages is that sometimes small changes to DNA sequences can actually lead to larger, more elaborate structures in organisms, such as more complex brains.

To the University of Sheffield'sRhonda Snook, that concept is as interesting as the"titillating"penis findings.

Some"might think {the switches} are marginal,"said Snook, who was not involved in the new research.

But these small tweaks"could have potentially really profound effects on the way that organisms evolve from their ancestors."

Monogamy Led to Simpler Penises?

For instance, such minor genetic shifts have made human penises smoother and simpler over time, according to the study, which appears tomorrow in the journalNature.

This may be because men no longer need the additional hardware. In some modern animals, such as domestic cats, penile spines help males fertilize females when sperm competition inside the female is fierce.

For instance, the spines can break through copulatory plugs, or coagulated secretions of fluids placed inside the female by other males to prevent different sperm from fertilizing the egg.

(See"Sperm Recognize 'Brothers,' Team Up for Speed.")

But most women today are monogamous, and the males"are not just present during the competitive act of fertilization—they establish long-term relationships with females,"Kingsley said.

Snook, who studies the evolution of sperm form and function, said theories linking simpler genitalia to monogamy are still tenuous.

For instance, a phylogenetic analysis—a study comparing the presence or absence of spiny penises in different organisms over time—would offer more insight.

Human Evolution an"Impenetrable Mystery"

Overall, this type of sophisticated DNA research became possible just ten years ago, when the human genome was published, Snook noted.

"We've got just such an amazing power now to know a lot more about how evolution really occurs and how it changes,"she said.

(Related:"Human Genome Shows Proof of Recent Evolution, Survey Finds.")

Study co-author Kingsley added:"We happen to live in this magic time where we have the complete genome sequence of ourselves and our relatives."

Finding out how we became who we are"can be a huge, impenetrable mystery,"he said, but we're"beginning to tease out some of the molecular differences that make us human."

National Geographic News

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Pictures: Prehistoric American Skull Found in Sea Cave?

Divers carefully place a marker near a human skull found upside down in a large underwater cave near the Caribbean Sea onMexico'sYucatán Peninsula (map)in 2007.

Based on the skull's location, the team believes the remains ended up there about 10,000 years ago—just before the then dry cave was inundated as sea level began rising.  If confirmed, that age would make the skull one of the oldest known remains of an early American, or Paleo-Indian.

Though the skull was found alongside bones of a mastodon and other prehistoric animals in 2007, news of the find was released only late last month, to allow time to properly document the site, train the divers in archaeological practices, and coordinate with authorities.

The divers had previously seen Ice Age animal remains in surrounding caves, but the human skull was a surprise."That's one of the beauties of exploration—you never know what you're going to find,"diverAlberto Navasaid.

Now comes the tricky part."We want to figure out the story of Hoyo Negro and how the human and animal remains got there,"said Nave, of the Projecto Espeleológico de Tulum (PET) organization and Global Underwater Explorers (GUE).

(Read the account of a National Geographic archaeologist involved with the project:"Skull in Underwater Cave May Be Earliest Trace of First Americans.")

—Ker Than

Note:National Geographicmagazinepartially funded archaeological training for the divers on this expedition. Both the magazine and National Geographic News are parts of the National Geographic Society.

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Best Rare-Bird Pictures of 2010 Named

A picture of an endangeredAsian crested ibissoaring overChinais a first-prize winner in the first annual World's Rarest Birds international photo competition, organizers announced in January.

Launched in 2010, the competition ranked pictures of birds that fall into three categories determined by theInternational Union for Conservation of Nature: endangered or data deficient, critically endangered or extinct in the wild, and critically endangered migratory species.

The above shot took top honors in the"endangered or data deficient"category. The Asian crested ibis once thrived in Russia, Japan, and China, but its population has shrunk to about 250 in China's Shaanxi Province. Agricultural activities have probably affected the bird by reducing available feeding grounds, according to the World's Rarest Birds website.

(Related:"Birds in 'Big Trouble' Due to Drugs, Fishing, More.")

A panel of five independent judges—including two wildlife photographers, a wildlife artist, a citizen interested in birds, and a book editor—rated the entries on image quality, subject rarity, and aesthetics. Winning images will be featured in the book The World’s Rarest Birds, to be published in 2012 by WILDGuides.

The book's"key message is poignant—a large proportion of the world's birds, including every one depicted, is threatened with extinction,"Andy Swash, managing director of WILDGuides, said in a statement.

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Male Monkeys Wash With Urine to Attract Females?

Talk about"eew"de toilette—male monkeys that wash with their own urine may be putting out an irresistible scent to females, a new study suggests. (See monkey pictures.)

Males and females of several monkey species pee into their hands and then vigorously rub the fluid into their fur. Scientists have posed various theories to explain the behavior, which range from regulating body temperature to communicating aggression.

(See"Women's Tears Reduce Sex Drive in Men, Study Hints.")

Now,brainimages of female capuchin monkeys have revealed that male urine sends sexual signals, according to study leaderKimberley A. Phillips, a psychologist at Trinity University in San Antonio, Texas.

"Apparently, a male covered in urine is quite attractive,"Phillips said.

Monkey Urine Reinforces Dominance?

During MRI tests, Phillips and colleagues exposed four female monkeys to urine previously collected from adult males and juvenile males. All of the monkeys used in the experiment were born in captivity.

The team found that parts of the females' brains associated with smell and sexual behavior were activated more by the adults' urine than by the juveniles', Phillips said.

Phillips doesn't know exactly what message urine-washing males are sending the females. But it's possible the urine—which contains the male sex hormone testosterone—is another way for females to assess a male's social status, she noted.

(See"'Makeover' Birds Get Testosterone Jolt.")

For instance, sexually receptive female capuchins will solicit alpha males—which have more testosterone in their pee—about 80 percent of the time, she said.

Phillips added that she hasn't fully explained the purpose of urine washing, especially since females and juveniles also engage in this behavior. In addition, she hasn't yet tested how male brains respond to female urine.

Sexual signaling, she added, is"certainly not the whole picture."

The urine-washing study appeared online February 15 in theAmerican Journal of Primatology.

National Geographic News

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Dolphin-Baby Die-Off in Gulf Puzzles Scientists

This winter an alarmingly high number of youngbottlenose dolphinsin theGulf of Mexico (map)have been washing up dead on U.S. shores, government scientists report.

The reason for the die-off is a mystery, and experts are urging caution in drawing any connections to last year'sBP oil spill.

"Everybody wants to jump to that conclusion ... but at this point in time, it's too early to tell,"said Blair Mase, coordinator of the Southeast Marine Mammal Stranding Network of theNational Atmospheric and Oceanic Administration (NOAA).

Since January 1, 80 dead dolphins have been discovered along the coasts ofLouisiana,Mississippi,Alabama, andFlorida, according to the latest NOAA figures.

Forty-two of the dead were calves. Most of the juvenile dolphins are washing up in Mississippi and Alabama, because dolphins typically give birth and raise calves along the shallow shores of those states.

The normal gestation period for the dolphins is one year, and mothers usually give birth in March and April, so scientists think the affected calves are either being aborted, stillborn, or born prematurely.

"That's one part of the investigation that we're going to be looking at very carefully,"Mase said.

"We'll methodically score each animal that has come ashore to determine if, in fact, it was an aborted calf or an animal born alive."

(Related:"Dolphin Mystery: What's Killing Firstborn Calves?")

BP Oil Spill"a Factor We Need to Consider"

Dolphin die-offs—which scientists call unusual mortality events—occur every few years. But this one stands out, because young dolphins appear to be hardest hit, marine biologistMoby Solangisaid.

"Usually in a stranding, you have a mixture of animals—males, females, adults, calves—but this one is distortedly focused on neonates,"said Solangi, director of the Institute for Marine Mammal Studies (IMMS) in Gulfport, Mississippi, which is helping to investigate the deaths.

Also unusual: Only dolphins appear to be affected so far. No mass deaths of turtles, fish, or birds have been reported for this die-off. (Also see"Why Are Birds Falling From the Sky?")

Known causes of dolphin die-offs include unusually cold waters, ocean biotoxins, and diseases.

NOAA's Mase said scientists are investigating all of these factors and are not ruling out a possible connection to the BP oil spill.

"It's something that we are including in our investigation,"Mase said.

IMMS's Solangi agreed that the BP oil spill"is a factor that we need to consider."

"The oil spill lasted several months, and it covered tens of thousands of square miles and much of the habitat of these animals."

IMMS scientists are currently performing necropsies on the dead dolphins to try to determine causes of death. The process—including analyzing tissue samples for signs of diseases, viral infections, and toxins—could take several weeks or months, Solangi said.

(Relatedpictures: ten animals at risk due to the Gulf oil spill.)

Oil Link Tough to Prove

While a link between last year's BP oil spill and this year's dolphin deaths is possible, it could be very difficult to prove, saidCraig Matkin, a marine biologist at the North Gulf Oceanic Society in Alaska.

Matkin co-authored a study in 2008 that looked at the effects of the 1989Exxon Valdezoil spill on killer whale populations in Alaska's Prince William Sound. (ReadNational Geographicmagazine's 1990coverage of theExxon Valdezoil spill.)

"I'm not overly optimistic that they're going to be able to find a link,"he said.

One reason is that—unlike other environmental toxins, such as the pesticide DDT—the hydrocarbon molecules in oil are quickly processed by the body and do not persist in tissues, Matkin explained.

Scientists also don't have a good idea of how the spill might have affected dolphins still in the womb.

Oil is thought to affect marine animals through inhalation or direct and indirect ingestion—for example, by eating taintedfish. But the calves now showing up dead may not have even been conceived before or during the worst weeks of the spill and thus were not exposed to the oil directly.

Dolphin Die-offs Largely Cold Cases

In his 2008 study, Matkin's team concluded that theExxon Valdezspill affected Alaskan killer whale populations for decades after the event. After inhaling oil vapors or eating oil-coated seals, for example, the whales experienced everything from"mild irritation"to instant death, the study days.

It's unknown how the 1989 spill affected calves. Killer whales tend to give birth in deep water, so dead calves are much less likely to wash ashore.

(Related:"Exxon Valdez Anniversary: 20 Years Later, Oil Remains.")

Matkin pointed out key differences between the two events.

"This is just not the same kind of situation,"he said."We were following individual animals for a period of time before the{Exxon Valdez}spill, so we knew who was missing, down to the individual.

"It's very different when you have a bunch of unknown animals stranded on a beach and you don't know anything about their history."

NOAA's Mase said it's possible that no satisfactory answer will ever be found for the dolphin-baby die-off.

"There have been 14 {unusual mortality events} since 1990,"she said."And of those 14, we've only been able to determine the causes for 6."

forNational Geographic News

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8 Jules Verne Inventions That Came True (Pictures)

As made interactively evident by a retro-futuristicGoogle doodle, Tuesday would have been the 183rd birthday ofJules Verne. Had he lived to see 2011, the French science fiction writer also would have seen many of his fanciful inventions made real—more or less.

In perhaps his most famous novel,Twenty Thousand Leagues Under the Sea,Verne's Captain Nemo travels the world's oceans in a giant electric submarine, theNautilus—the inspiration for the portholed Jules Verne Google doodle.

Aside from its organ, formal dining room, and other luxuries, theNautilusisn't all that different from some modern subs, such as the circa-1964, three-passengerAlvin(pictured), which is powered by lead-acid batteries.

LikeAlvin,theNautiluswas fully powered by electricity,"which at that time had a kind of magical aura,"saidRosalind Williams, a historian of technology at the Massachusetts Institute of Technology (MIT).

In the book Captain Nemo describes electricity as"a powerful agent, obedient, rapid, easy, which conforms to every use, and reigns supreme on board my vessel."

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Pictures:"Remarkable" Ice Age Fossil Cache Found

Scientists unearth an Ice Age bison skull near Snowmass Village,Colorado, on November 6.

"I'm trying to think of a cooler fossil that I've even seen in my life,"dig team memberKirk Johnson, chief curator at the Denver Museum of Nature& Science, said in a statement.

The bison skull is part of a"bumper crop"of Ice Age animals recently discovered at the site, including American mastodons, Columbian mammoths, tiger salamanders, and a Jefferson's ground sloth—the first ever found in Colorado, according to the Denver museum. Construction workers stumbled upon the Ice Age treasure trove in October while working on a reservoir-expansion project.

While winter weather has put a hold on excavations at the site, scientists are analyzing many of the 600 fossils found so far—thought to date to at least 130,000 years ago—at the Denver museum's laboratory. (See"Comet"Shower"Killed Ice Age Mammals?")

Team memberScott Elias, a paleoecologist at Royal Holloway, University of London, also announced in January that he has extracted beetles and other insects from peat samples taken from the site.

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Photos:"Zombie" Ants Found With New Mind-Control Fungi

A stalk of the newfound fungus species Ophiocordyceps camponoti-balzani, grows out of a"zombie"ant's head in a Brazilian rain forest.

Originally thought to be a single species, called Ophiocordyceps unilateralis, the fungus is actually four distinct species—all of which can"mind control"ants—scientists announced Wednesday.

The fungus species can infect anant, take over itsbrain, and then kill the insect once it moves to a location ideal for the fungi to grow and spread their spores.

(Relatedpictures:""Zombie"Ants Controlled, Decapitated by Flies.")

All four known fungi species live inBrazil's Atlanticrain forest, which is rapidly changing due toclimate changeanddeforestation, said study leaderDavid Hughes, an entomologist at Penn State University.

Hughes and colleagues made the discovery after noticing a wide diversity of fungal growths emerging from ant victims, according to the March 2 study in the journalPLoS ONE.

"It is tempting to speculate that each species of fungus has its own ant species that it is best adapted to attack,"Hughes said.

"This potentially means thousands of zombie fungi in tropical forests across the globe await discovery,"he said."We need to ramp up sampling—especially given the perilous state of the environment."

—Matt Kaplan

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"Dramatic" New Pictures: Rare Javan Rhino Spotted

A Javan rhinoceros triggers a camera trap inIndonesia's Ujung Kulon National Park in late 2010. The image was released this week byWWF-Indonesiaand Indonesia's National Park Authority.

A motion-activated video camera also recorded"dramatic"footageof four of the rhinos, deemed critically endangered by theInternational Union for Conservation for Nature. At fewer than 40 individuals, the Javan rhino may be the rarest mammal on the planet, according to WWF.

(Seepictures:"14 Rarest and Weirdest Mammal Species Named.")

Though the videos and pictures are"great news,"the animals still face grave threats, WWF-US chief scientistEric Dinersteinnoted in a statement.

For instance, an eruption of the nearby Anak Krakatauvolcanocould easily wipe out all life on the peninsula that the rhinos call home.

"There are no Javan rhinos in captivity,"he said."If we lose the population in the wild, we've lost them all."

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Pictures: 10 Most Threatened Forest Hot Spots Named

A boy in a basin navigates through a floating village in Tonle Sap Great Lake,Cambodia, on September 13, 2009.

The lakes, rivers, and floodplains of theIndo-Burma region (see map)crisscross one of the world's top ten at-risk forest biodiversity hot spots, according to a new ranking created by the nonprofit Conservation International. Biodiversity hot spots, first defined in 1988, are areas that conservationists deem most critical for saving species.

The areas included in the 2011 report each harbor at least 1,500 native plant species but have lost 90 percent or more of their original habitats. The report was compiled to coincide with the United Nations'International Year of Forests. (See"Tigers, Elephants Returning to War-Torn Cambodia Forest.")

Forests cover only 30 percent of the planet's area but are home to 80 percent of the world's land animals and plants, according to the conservation group. In addition to housing diverse species, forests provide"vital benefits"for humans, including timber, food, shelter, recreation,fresh water, and erosion prevention, according toOlivier Langrand, Conservation International's international policy chief.

"Forests are being destroyed at an alarming rate to give room to pastures, agricultural land, mineral exploitation, and sprawling urban areas, but by doing so we are destroying our own capacity to survive," Langrand said in a statement.

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