Blueberries, Already a Superfood, May Help Combat PTSD

Blueberries are not only scrumptious – they may be able to protect us from cardiovascular disease, cancer, memory loss, and maybe even PTSD in the future.

Bears go bats over blueberries. In blueberry season, bears will travel miles just to get their paws – well, lips – on a ripe and scrumptious blueberry patch. And an increasing amount of scientific evidence indicates that we should all be as pro-blueberry as the bears.

Blueberries these days are touted as a superfood – an unofficial term that refers to low-calorie edibles with greater-than-average (even super) nutritional and health benefits. Among these – along with the yummy blueberries – are broccoli, kale, kiwi fruit, pomegranates, beans, salmon, and sardines.

The notable health value of blueberries derives in part from their lush content of antioxidant flavonoids – compounds that not only make blueberries blue, but also act to mop up free radicals.

Blueberry fields turn bright red in Maine during the autumn season. Photograph by B. Anthony Stewart, National Geographic

Free radicals are highly reactive molecules with the potential to damage cell integrity and mess with our all-important DNA. These are products of normal body metabolism – each of our body’s cells generates about 20 billion every day – and we also pick up a good many from pollutants and radiation in the environment. Free radicals, as destructive as molecule-gobbling Pac Men, have been implicated in everything from cardiac disease to cancer, memory loss, autoimmune disorders, and neurodegenerative diseases such as Alzheimer’s and Parkinson’s disease.

Our bodies do their best to beat these off – we have a couple of enzymes tailor-made to combat and eliminate free radicals – but with age and environmental exposure, they can begin to overwhelm us. We can help protect ourselves with antioxidant-enriched foods – and when it comes to antioxidants, blueberries are at the top of the food heap. According to the U.S.Department of Agriculture, blueberries, antioxidant-wise, out-rank everything but red beans – and red beans aren’t ahead by much.

The latest in the array of blueberry bennies is their possible potential to combat post-traumatic stress disorder (PTSD). About 8 percent of the American population suffers from PTSD at some point in their lives, due to emotional or physical trauma, and – at an estimate – PTSD afflicts up to 20 percent of veterans. Current, but not particularly effective, treatments for PTSD are drugs known as selective serotonin re-uptake inhibitors or SSRIs – that is, medications that boost levels of serotonin, a neurotransmitter associated with mood disorders.

A sprig of black highbush blueberry blossoms and berries from the February 1919 issue of National Geographic. Illustration by Mary E. Eaton

Some recent research, however, indicates that blueberries may be a helpful alternative, at least in rats. Experiments conducted by Philip Ebenezer and colleagues at Louisiana State University involved rats which developed PTSD after being (deliberately) terrified by cats. The researchers found that rats who were fed blueberries following their traumatizing experience had markedly higher serotonin levels than rats fed a blueberry-less control diet, suggesting a better recovery. If blueberries have similar effects on neurotransmitter levels in human beings, they may help alleviate the problems of the severely traumatized.

Other health benefits of blueberries have been in the news for a while. A cup of blueberries a day, according to the Journal of the Academy of Nutrition and Dietetics, may reduce the risk of cardiovascular disease. Other studies indicate that blueberries decrease the risk of prostate cancer, combat urinary tract infections, reduce age-related memory loss, and promote brain health. Various experiments have shown that blueberries boost brain power, variously upping memory, learning, and cognitive functions – among these reasoning skills, decision making, verbal comprehension, and numerical ability. To be fair, there are other foods that are also excellent sources of brain-bolstering flavonoids – among them wine, tea, dark chocolate, and tofu. But blueberries are also great sources of vitamin C – and, since a cup of blueberries adds up to a mere 80 calories, they’re not about to make you fat.

What to make of all of this? Scientists tell us not to go overboard. Popular claims for superfoods can be exaggerated; and chances are that blueberries aren’t a universal panacea.

But a cup a day sure can’t hurt.

Photo of the Day Ram’s Eye

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JANUARY 12, 2015

Ram’s Eye

Photograph by Dawn Wilson, National Geographic Your Shot

“During a recent trip to Wyoming to photograph wildlife, I made a point of stopping in the North Fork Canyon outside Cody, Wyoming, to photograph the bighorn sheep during their annual rut,” writes Your Shot member Dawn Wilson. “The weather had been warm, so activity was a bit low. But on my final drive out of the canyon before heading home, I came upon two rams fighting nonstop, to the point that each had a bloody nose. An hour into the battle, this ram, which wound up being defeated, stopped for the briefest of moments to look at me, almost like a plea for help.”

Wilson’s picture recently appeared in Your Shot’s Daily Dozen.

This photo was submitted to Your Shot. Check out the new and improved website, where you can share photos, take part in assignments, lend your voice to stories, and connect with fellow photographers from around the globe.

Arctic's 'Penguins of the North' Find Workaround to Climate Change New study finds that little auks are adjusting their food supply, raising questions of adaptation.

Little auks returning from sea to nest after feeding on copepods.

PHOTOGRAPH BY PAUL NICKLEN, NATIONAL GEOGRAPHIC

Brian Clark Howard

National Geographic

PUBLISHED JANUARY 12, 2015

What's New: The latest research on little auks, sometimes called "penguins of the north," reveals a surprising response to a rapidly warming Arctic: The birds make up for food lost to the effects of climate change by catching prey that were stunned by the cold water running off melting glaciers—another effect of climate change.

The study, published Monday in the journal Global Change Biology, is the first to examine the feeding habits of little auks as Arctic ice is lost. Scientists watched the birds in Franz-Josef Land, off the northern coast of Russia, during an expedition supported by the National Geographic Society.

Since 2005, the auks' water has become essentially ice-free in summer, reducing the numbers of tiny animals known as zooplankton, a key food source for the auks. Zooplankton normally congregated around sea ice, but now the birds have shifted to eating zooplankton that are stunned—and thus easier to catch—by cold water running off glaciers melting on land. (See photos from the expedition.)

The shift hasn't been entirely seamless. Little auk chicks have been growing just as quickly as they did before 2005, but the adults' body mass has dropped an average of 4 percent since the early 1990s. That might not sound like much, but "we don't know what the weight loss is that would really harm them," says Enric Sala, a co-author of the study and a National Geographic explorer-in-residence.

Little auks return to land in the Arctic, after feeding on plankton at sea.

Why It Matters: Little auks are considered especially vulnerable to climate change. The birds are often considered an indicator species of the Arctic, raising red flags for ecological changes.

"It's good news that the little auks are adapting now," Sala says, "but because the system is changing continuously, we don't know how long they will be able to keep up."

The birds also play an important role in the Arctic ecosystem, so other species could be affected by changes in little auks. (Learn about big waves forming in an ice-free Arctic.)

The Big Picture: To date, the Arctic has warmed twice as fast as lower latitudes have. The Arctic will be essentially free of summer sea ice by the 2030s, with drastic implications for species from seabirds to polar bears, according to the Intergovernmental Panel on Climate Change. (Similar forces are at work around Antarctica.)

Some Arctic species may go extinct, scientists have warned, but precisely how individual species will respond is largely unknown and will probably hold some surprises, as this new paper suggests.

What's Next: The scientists estimate that all continental glaciers will disappear from Franz-Josef Land within about 180 years, although meltwater could decrease significantly before that. As that happens, it's unclear if the birds will be able to find enough food.

"Ultimately, there is only one thing we can do for little auks, polar bears, and everything else that is affected," says Sala. "That's to reduce emissions of greenhouse gases."

Photo of the Day Flashy Feathers

JANUARY 9, 2015

Flashy Feathers

Photograph by Ivan Lesica, National Geographic Your Shot

"One of my favorite places to photograph exotic birds is in New York's zoo in Central Park," says Your Shot community member Ivan Lesica, who took this photo. "On a high branch in a bright spot with a deep shadow behind it, I noticed a beautiful [Nicobar] pigeon, one of my favorite birds in the zoo. I knew that the bird's glorious colors would 'explode' if the bird would slightly move its wings. Waiting for the right moment was the name of the game. I did not have to wait long. The bird decided to stretch its wings, and I was fortunate enough to be there to capture it."

Lesica's picture recently appeared in Your Shot's Daily Dozen.

This photo was submitted to Your Shot. Check out the new and improved website, where you can share photos, take part in assignments, lend your voice to stories, and connect with fellow photographers from around the globe.

Watch: Fishermen Catch Huge Numbers of Live Venomous Sea Snakes

Watch: Fishermen Catch Huge Numbers of Live Venomous Sea Snakes

Scientists sound a conservation alarm on the harvest of over 80 tons of sea snakes each year in the Gulf of Thailand.

National Geographic

PUBLISHED JANUARY 8, 2015

Fishermen wading barefoot through a writhing ball of venomous serpents can pay a high price for participating in the Gulf of Thailand's (map) sea snake harvest. Some die from snakebites, according to a recent study that suggests the snake catch may be one of the biggest hauls of marine reptiles in the world.

Scientists published estimates of the catch size in the journal Conservation Biology in December, along with some of the first research documenting who's buying and selling sea snakes and the fishery's indirect role in rhino poaching.

Fishermen bitten by their deadly catch believe that drinking ground-up rhino horn—or putting chunks of horn on the wound—can cure them. (See "Why African Rhinos Are Facing a Crisis.")

Caught in the glare of artificial lights, these sea snakes are destined for dinner plates and use in traditional medicines.

PHOTOGRAPH BY ZOLTAN TAKACS

Some scientists are raising concerns about the practice. Little is known about the region's sea snakes, including what species and how many live there, so it's not clear whether the harvest is sustainable.

An overharvest, these researchers worry, could jeopardize potential medicinal discoveries. Compounds in venom, once processed and administered in controlled amounts, can be beneficial in treating human ailments like heart disease.

The sea snake catch—a side job for the region's Vietnamese squid fishers—takes in over 80 tons (73 metric tons) of the marine reptile annually. That's roughly 225,500 individual sea snakes per year, valued at over $3 million.

Fishermen bitten by sea snakes use treatments that contain rhinoceros horn (shown above), which has no proven medical benefits.

PHOTOGRAPH BY ZOLTAN TAKACS

The fishery of opportunity occurs during squid hunts conducted each lunar cycle before the moon gets too bright.

Most of the sea snakes end up in China and Vietnam, says the study's lead author Zoltan Takacs, whose work was funded by the National Geographic Society. Restaurants use the meat in soups and employ either the whole animal or just its blood in alcoholic beverages.

The snake's organs, including the heart and gallbladder, play central roles in concoctions meant to relieve maladies such as joint pain, anorexia, and insomnia.

Little is known about sea snakes in the Gulf of Thailand, so researchers aren't sure whether current harvest levels are sustainable.

PHOTOGRAPH BY ZOLTAN TAKACS

Lost Medicines?

Hunting snakes for food or medicinal purposes is nothing new, says John Murphy, a sea snake researcher at the Field Museum in Chicago. "[And] the Gulf of Thailand harvest seems to be driven by the Chinese market," says the biologist, who was not involved in the study.

Snakes figure prominently in traditional Chinese medicines, Murphy says. Coupled with the country's strong economy, "the demand for snakes—not just sea snakes—is huge." (See why "China's Expanding Middle Class Fuels Poaching, Decadence in Myanmar.")

Fishermen handle their highly venomous catch with little or no protection, often wading into pens barefoot and grabbing sea snakes with their bare hands.

PHOTOGRAPH BY ZOLTAN TAKACS

The demand extends to Western medical practices in other parts of the world, says Takacs, a pharmacologist specializing in animal toxins at ToxinTech in New York City.

"Out of the top three heart attack medications, two of them come from snake venoms," he says.

The potential uses of venoms in the sea snakes in the Gulf of Thailand haven't been studied, says Takacs. "So we absolutely have no idea what kind of venoms or toxins we are eating away."

Follow Jane J. Lee on Twitter.

Sea snakes destined for market are sorted by weight and can fetch up to $20 per pound.

PHOTOGRAPH BY ZOLTAN TAKACS

Why Do "Disco Clams" Put On Brilliant Light Shows? The mollusk's flamboyance may warn predators or lure prey, research suggests.

A pair of disco clams share a crevice in Raja Ampat, Indonesia.

PHOTOGRAPH BY LINDSEY DOUGHERTY, UNIVERSITY OF CALIFORNIA, BERKELEY

for National Geographic

PUBLISHED JANUARY 6, 2015

The so-called "disco clam" is one eye-catching mollusk—nestled in coral reefs off Indonesia, the animal generates brilliant flashes of light that earned it its festive name.

Though fascinating, this flamboyant bivalve (Ctenoides ales) is still poorly understood, somethingLindsey Dougherty, a graduate student at the University of California, Berkeley is trying to change. Earlier this year, Dougherty shed light on how the clam's flashing works—by reflecting light through tiny bits of silica near the edge of its shell, and not throughbioluminescence like other species.

Now Dougherty and her colleagues have gotten closer to why the clams put on their marine light show: to warn predators or lure prey. (Watch a video of the ocean's flashy dressers.)

"Most animals don't do something that's energetically costly unless there's [a payoff]," said Dougherty, who presented the new research this week at the annual conference of the Society of Integrative and Comparative Biology in West Palm Beach, Florida.

For instance, "light displays are often used to try to attract a mate or to attract prey, and some of the displays can also be defensive, like with the [extremely poisonous] blue-ringed octopus," she said.

Shedding More Light on the Disco Clam

Dougherty and her team tested three hypotheses for the clam's brilliance: attracting a mate to spawn eggs, catching the attention of light-seeking plankton, or sending a warning to potential predators.

The scientists tested the three hypotheses by introducing threats, food, and the opposite sex into tanks with captive clams and observing how the mollusks reacted. (See National Geographic's pictures of colorful sea creatures.)

The team found little evidence that the disco flashing draws in suitors, since the clams' eyesight is likely too poor to see the flashes.

Watch a video of the flashing clam.

But the other two hypotheses bore (at least preliminary) fruit.

When the team moved a fake predator toward a disco clam, its flash increased in frequency, from 1.5 to 2.5 hertz, she said. "So it has a really obvious reaction to potential predators."

When plankton were introduced to the tank, the disco clams flash rate also increased, although not as much.

In both instances, "they get excited, you could say. Excited or scared."

Leaving a Bad Taste

The team was surprised to find sulfur in both the tentacles and mantle—the fleshy protruding part—of the disco clam.

"Sulfur is the main ingredient in sulfuric acid, which is really distasteful to predators," Dougherty said.

PHOTOGRAPH BY LINDSEY DOUGHERTY, UNIVERSITY OF CALIFORNIA, BERKELEY

The disco clam has about 40 eyes that are located between their tentacles.

To further test the predator hypothesis, the team introduced the mantis shrimp, a type of aggressive crustacean, into the tank. (Also see "5 of Nature's Wildest Animal Showdowns.")

The shrimp then started acting strangely: "We have some footage of a mantis shrimp sort of recoiling and then cleaning its mouth parts and then going into a catatonic state after interacting with the disco."

Dougherty says that suggests that the predator ignored the clam's flashing only to taste something it didn't like, like sulfuric acid.

She added that more research is necessary in the wild to determine whether plankton can actually see the disco's visual displays, and whether similar types of clams also secrete sulfuric acid.

That's no problem for Dougherty. "For me," she said, "the most fun place is underwater with the clams."

For Orphaned Elephant Calf, Harrowing Rescue Ends in Hope In Kenya, baby elephant fights to survive after poachers poisoned her mother.

PHOTOGRAPH BY SIDDHARTH RAMASWAMY

A tourist photographs a baby elephant and her mother on Kenya’s Masai Mara plains—just a day before the mother was killed by poachers. 

 

MASAI MARA, Kenya—One day last October, a mother elephant and her ten-month-old calf were seen playing together on the plains of the Masai Mara National Reserve when a passing tourist photographed the tranquil scene.

Twenty-four hours later, on October 22, the young calf was spotted again—this time standing over her mother's poisoned carcass, seemingly reluctant to leave her side.

The young calf had her head down, and her trunk was draped across the mother's back when Richard Roberts, from the Mara Elephant Project, arrived.

After examining the dead mother more closely, he found a poisoned spear wound in her cheek, indicating a fatal attack by ivory poachers.

The hungry orphan tried to suckle, but the mother gently pushed her away.

The mother was still nursing the calf before the lethal, fast-acting poison stopped her heart, and now, as she lay motionless on the dry plains, the baby was left without a source of food.

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When the herd slowly began to move away, the calf followed behind another lactating mother and her calf. The hungry orphan tried to suckle, but the mother gently pushed her away.

"An orphan will sometimes get taken in by another mother in a breeding herd," said Angela Sheldrick, executive director of the David Sheldrick Wildlife Trust(DSWT), an orphan-elephant rehabilitation facility based in Nairobi. 

"But she will only share her milk in situations where it would not jeopardize the health of her own infants."

It was obvious that the mother was denying the orphan milk. Deprived of sustenance, the young elephant would soon weaken in the heat of the day, fall behind the herd, and likely die on the plains.

The herd was moving toward the Tanzanian border, and if the baby elephant crossed it, a rescue mission would be impossible. 

The young elephant’s chances of survival hinged on a successful capture and transport operation, so the trust's rescue unit was called in from Nairobi to assist with the mission.

See a video of the dramatic rescue:

The Rescue

In the meantime, the matriarch of the herd had become extremely protective toward the orphaned baby, and the rescuers faced a difficult task in separating the calf from her and the rest of the herd.

After carefully maneuvering a Land Cruiser into place, they isolated the baby from the matriarch and leaped from the vehicle, restraining the little elephant by hand.

They wrapped the traumatized baby in warm blankets and hoisted her into the bed of the four-by-four and rushed her to the Mara airstrip.

As the Cessna took off, the infant lay quietly, her pale eyes staring up at the trust's elephant keepers, who gave her tranquilizers to calm her as they bumbled east over the Great Rift Valley, en route to an unfamiliar new world.

The team landed in Nairobi at dusk and offloaded the sleeping calf onto a flatbed truck. She finally arrived at the DSWT nursery, in Nairobi National Park, after dark, where she thankfully accepted a fresh bottle of milk.

The elephant calf made it through the night, and in the morning the team named her Roi.

After a flurry of media coverage around the incident, little has been revealed about Roi's progress at the orphanage.

The grieving ten-month-old calf stands over her poisoned mother, gently caressing her body as other members of her herd crowd around. 
PHOTOGRAPH BY SWATI PRASAD SIDDHARTH

The Power of Grief

"The first few weeks for a young elephant orphan are always critical," Sheldrick said.

The first few weeks for a young elephant orphan are always critical.

"Like humans, elephants have a remarkablecapacity for emotions, and we see behaviors linked to this every day.

"They show signs of depression, which manifests in listless and withdrawn behavior and wanting to spend long periods in solitude. The frightened elephants have to learn to adapt to their new surroundings."

Sadly, not all elephants make it, Sheldrick explained. If the feeling of grief or distress becomes too much, they can literally give up on life, refusing food or water.

VIRGINIA W. MASON AND LISA R. RITTER, NGM STAFF. SOURCES: DAVID SHELDRICK WILDLIFE TRUST; IAIN DOUGLAS-HAMILTON, SAVE THE ELEPHANTS; PATRICK OMONDI, KENYA WILDLIFE SERVICE; AFRICAN ELEPHANT STATUS REPORT 2007, IUCN; WORLD DATABASE ON PROTECTED AREAS

 

Ensuring that the orphans feel like part of a herd—a family—is extremely important, along with constant touch and attention from the keepers who feed and nurse them on their road to recovery.

Roi Doing Well

After two days in the stockade, Roi was let out with the other orphan elephants in the Nairobi herd. She was immediately comfortable and content among the older orphans, who gave her the attention and love she needed.

She craved her milk bottle and gravitated to the keepers for her three-hourly feedings.

Roi will live among the Nairobi herd until the age of three, when she'll be moved to one of the DSWT rehabilitation centers in the Tsavo national parks. There, she'll be weaned off milk and reintroduced to wild elephants in the area.

It can take as long as ten years for an orphan to choose to leave her adopted family and rejoin a wild herd.

After a dramatic rescue, the baby (at right) was taken to the elephant nursery at the David Sheldrick Wildlife Trust, in Nairobi. Comforted among fellow orphans, Roi, as the keepers christened her, is doing well.

 
PHOTOGRAPH BY DAVID SHELDRICK WILDLIFE TRUST

"As a young milk-dependent calf, Roi wouldn't have survived without our intervention, and she's now been given a second chance," Sheldrick said.

"Over the years, we've raised and reintroduced over 90 elephants into the wild, and 82 infant elephants are currently reliant on us," she said.

"The poaching situation is escalating in East Africa, and we need to be ready to provide that same lifesaving care for other orphaned elephants in need."