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for May, 2010.
Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.
Well, it looks like its time to clean out the animal file again and I’ve got some lovely bizarre animals for you. Our first stories deal with the hard stuff and I’m not talking about alcohol!
If you ever gone wading in the waters around the Marianas, you may have had an unfortunate encounter with a sea urchin. Those black guys with the long spines are called Diadema urchins and I know several people who’ve had the misfortune to step on one or back into one. The spines aren’t poisonous, but getting stabbed with the equivalent of a knitting needle always hurts.
Diadema urchins are free roving, but many urchins live at the tide line and you can see them at low tide. Just look below the high tide water line on any rock and you’re likely to see an urchin-sized hole with the spines of an urchin at the bottom of it.
So here’s your first science question of the day. How do sea urchins make holes in solid rock?
An international team of researchers has considered that very problem and come up with some interesting answers that may give engineer’s insights into creating ever-sharp tools or mechanical parts. It turns out that sea urchins dig themselves hiding holes into limestone rocks using teeth that don’t go blunt.
The urchins dig holes to fit their globular bodies using five teeth arranged in a pentagon. The teeth are like rodent teeth because they’re ground down at the tip but continue to grow on the other end throughout the animals’ lives. But here’s the amazing part. The teeth, which need to be harder and stronger than the rocky limestone they’re digging into, are made almost entirely of calcite – the same calcite that makes up much of the limestone.
How is this possible? In a series of studies spanning more than a decade, the researchers have discovered that the urchins’ secret lies in a combination of very ingenious design strategies.
The scientists found that the sea urchins’ teeth contain crystals of magnesium calcite, which are smaller, harder and denser than those of pure calcite. These crystals are concentrated at the grinding tip of each tooth, particularly in the tip’s center, where the most force is exerted in the course of grinding. The hard crystals are held at the center of the tip in a matrix of larger and softer calcite crystals.
In most teeth, a matrix of hard fibers contains a softer filling but the reverse is true for the sea urchin teeth. A matrix of relatively soft calcite fibers holds the harder magnesium calcite crystals, which allows these crystals to spread over the entire surface of the tooth. The presence of magnesium calcite crystals acts like sand paper that helps to grind down the rock.
But that’s not the only interesting innovation practiced by these spiny critters. The researchers have also used X-ray photoelectron emission spectromicroscopy and other high-resolution imaging methods to uncover yet another amazing structural feature of sea urchin tooth design. They found that all the crystal elements that make up the tooth are aligned in two different arrays, and that these arrays are interlocked like the fingers of folded hands, just at the tip of the tooth where the most wear occurs. The scientists believe that the interlocking produces a notched, serrated ridge that resembles a carpenter’s file. This ridge is self-sharpening: as the tooth is ground down, the crystalline layers break in such a way that the ridge always stays corrugated.
BURROWING INTO OTHER THINGS
So, digging holes in rocks may not be your thing, but how about burrowing into bone. No, that’s not my thing either, but researchers at the Monterey Bay Aquarium Research Institute (MBARI) in California have found the makings of a horror movie at the bottom of the Monterey Canyon. They’ve discovered eyeless, mouthless worms that lurk in the dark of the deep sea and then settle on dead animals and send out green "roots" to devour their bones.
These boneworms were first discovered in 2002 by researchers at MBARI while they were using a robot submarine to explore Monterey Canyon. But that wasn’t the end of the story. After "planting" several dead whales on the seafloor, a team of biologists recently announced that as many as 15 different species of boneworms may live in Monterey Bay alone.
After years of study, the researchers have begun to piece together the bizarre story of the boneworms, all of which are in the genus Osedax. The worms start out as microscopic larvae, drifting through the darkness of the deep sea. At some point they encounter a large dead animal on the seafloor. It may be a whale, an elephant seal, or even the carcass of a cow that washed out to sea during a storm. Following chemical cues, the tiny larvae settle down onto the bones of the dead animal.
Once there, the boneworms grow quickly. One end of each worm develops feathery palps, which extract oxygen from seawater. The other end of the worm develops root-like appendages that grow down into the bone. Bacteria within these roots are believed to digest proteins and perhaps lipids within the bones, providing nutrition for the worms.
Soon the worms become sexually mature. Strangely enough, they all become females. Additional microscopic larvae continue to settle in the area. Some of these larvae land on the palps of the female worms. These develop into male worms that never grow large enough to be seen by the naked eye.
The microscopic male worms then find their way into the tube that surrounds the female’s body. Dozens of them share this space, not eating at all, but releasing sperm that fertilize the female’s eggs. Eventually the female worm sends thousands of fertilized eggs out into the surrounding water, and the cycle begins again.
Between 2004 and 2008, the MBARI scientists towed five dead whales from Monterey Bay beaches and sank them at different depths in Monterey Canyon. Every few months team researchers would send one of MBARI’s remotely operated vehicles down to study the worms and other animals that colonized the whale carcasses.
To their surprise, each whale carcass yielded different types of boneworms and one carcass had four different kinds of worms. After examining the worms, they concluded that most of them were entirely new to science. The researchers also discovered that the worms will colonize cow-bones placed on the seafloor, showing they aren’t choosy about their food.
The scientists have done DNA analyses on all the different types of Osedax worms that have been discovered so far (including two species found off Sweden and Japan). Their findings suggest the worms could belong to as many as 17 different species, most of which have yet to be named. None of the worms appear to interbreed, despite the fact that some of them grow side by side.
Based on their appearance and similarities in their DNA, the researchers divided the boneworms into several groups. Some of the worms have feathery palps, which may be red, pink, striped, or even greenish in color. Others have bare palps. One type of boneworm has no palps at all. Its body forms a single, long, tapering tube, which curls at the end like a pig’s tail. This worm has evolved to live in the seafloor sediment near a dead animal. It sends long, fibrous "roots" into the mud, presumably in search of fragments of bone on which to feed.
If they know how fast the DNA of these worms changes over time, the researchers can calculate how long it has been since worms in the genus Osedax first evolved as a distinct group. Using one possible estimate of mutation rates, the researchers hypothesized that this group could have evolved about 45 million years ago — about the time the first large open-ocean whales show up in the fossil record. Alternatively, the worms may have evolved more slowly, which would suggest that the genus is much older, and first evolved about 130 million years ago. If this second estimate is correct, the worms could have feasted on the bones of immense sea-going reptiles during the age of the dinosaurs.
Eventually the researchers will give all these new worms their own species names. First, however, they must collect enough samples of each possible species for additional laboratory analysis and distribution to type-specimen collections. Like a classic horror story, the macabre saga of the boneworms will continue to thrill marine biologists for years to come.
This photograph shows a female of an unnamed boneworm in the genus Osedax, which has been carefully removed from the whale bone in which it was growing. This worm has green, feathery palps, which extract oxygen from seawater. At its lower end are an ovisac and bulbous "roots," which would normally be embedded in the whale bone. (Credit: Copyright 2009 Greg Rouse)
And now for our final story we move on to a truly amazing animal. If you check back to the story of the boneworms, you’ll discover that once they settle on their bone, they send ‘roots’ into the bone on one end and they grow palps on the other end to extract oxygen from seawater. Now this should not surprise you at all. Animals MUST have oxygen which is what makes us so dependent on the plants that produce it. Well, apparently not.
Italian researchers have discovered small animals deep in the Mediterranean Sea that live their entire lives without oxygen. Now this boys and girls should be even bigger news than the last episode of Lost! The scientists say in their report that these multicellular organisms are alive, metabolically active, and apparently reproducing despite a complete absence of oxygen.
The animals are called lociferans (members of the phylum Locifera). The lociferans are all microscopic (the biggest about a millimeter long) and they are among the newest animals discovered. They were first described in 1983. They firmly attach themselves to gravel on the ocean floor which probably explains why they weren’t discovered earlier.
The researchers retrieved sediment samples from an area on the ocean floor in the Mediterranean that is hypersaline, rich in sulfides and has no oxygen. They had previously discovered bodies of multicellular animals, but figured they were simply carcasses that had drifted down from the upper oxygenated waters. Much to their surprise, the lociferans they recovered were alive and some of them contained eggs.
Apparently, these tiny animals don’t have mitochondria (the organelles all animals harbor that allow the animals to metabolize oxygen), they have organelles resembling the hydrogenosomes found previously in protozoans that allow them to metabolized hydrogen and inhabit anaerobic environments.
This discovery opens a window on what life may have been like half a billion years ago before the plants provided enough oxygen to allow the rise of the animals.
Researchers have discovered small animals that live their entire lives without oxygen and surrounded by ‘poisonous’ sulphides, deep under the Mediterranean Sea. (Credit: Danovaro et al. / BMC Biology)
Animals that eat rock, eat bones and don’t breath oxygen. I think you’ll agree that it’s a strange and wonderful world we live in!
Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.
Greetings everyone! Well, I have a couple of follow-up stories for subjects that I featured over the last couple of weeks and then we’ll make a little trip to Rome. Our first follow-up is on global warming One of the things about global warming that I always figured was that I’d be pushing up daisies long before it became a serious enough problem to seriously affect my lifestyle. Now, I’m not so sure.
HOT ENOUGH FOR YOU?
According to NOAA (the National Oceanic and Atmospheric Administration) last month was the hottest April since record keeping began in 1880. The average land and sea temperature was 58.1 degrees Fahrenheit. That’s 1.37 degrees F above the 20th century average of 56.7 degrees F.
Not only was April the hottest April ever recorded, so were the first four months of 2010. The average temperature for January-April 2010 was 56.0 degrees which is 1.24 degrees F above the 20th century average.
Areas that were significantly warmer than average included Canada, Alaska, the eastern United States, Australia, South Asia, northern Africa and northern Russia. Cooler-than-normal places included Mongolia, Argentina, far eastern Russia, the western contiguous United States and most of China.
Climate experts said the El Nino warming of the tropical Pacific Ocean weakened in April and that Arctic sea ice was below normal for the 11th consecutive April, covering an average of 5.7 million square miles. On the plus side (and there aren’t many in this report) Antarctic sea ice extent in April was near average, just 0.3 percent below the 1979-2000 average. On the minus side, the North American snow cover for the month was the smallest on record for April.
So, ladies and gentlemen, no matter who or what we decide to blame for causing it, there is NO question that global warming is HERE! So, prepare for more power outages and buy lots of hand fans. And don’t go buying any beachfront property!
This map shows the April 2010 temperature variations from the 20th Century average.
Now that I have your attention, remember last week’s articles on the dangers of drug-resistant tuberculosis? Well, it isn’t just TB!
THE CLAP THAT KEEPS ON GIVING
I suspect that many Chamorus and Filipinos don’t have any idea why haoles get that funny look on their faces when an emcee gets up and says “Wasn’t that wonderful, folks? Now let’s all give them the clap!”. Because for us, ‘clap’ doesn’t mean applause. It’s street slang for a very nasty sexually transmitted disease, gonorrhea. And there’s some pretty bad news about some new strains of “the clap”. Like TB, gonorrhea is about to achieve superbug status.
Researchers from England have proposed the very real possibility that strains of Neisseria gonorrhoeae resistant to all current treatment options could emerge in the near future. They write that some strains of the bacteria that cause the disease are showing decreased sensitivity to the current antibiotics used to treat them — ceftriaxone and cefixime.
Gonorrhea is the second most common bacterial sexually-transmitted infection and if left untreated can lead to pelvic inflammatory disease, ectopic pregnancy and infertility in women. Current treatment consists of a single dose of antibiotic given in the clinic when prescribed, by mouth for cefixime and by injection for ceftriaxone.
Gonorrhea is already resistant to penicillin and a number of other antibiotics as well. Ceftriaxone and cefixime are still effective but there are signs that resistance particularly to cefixime is emerging and if gonorrhea becomes resistant to them, there are very limited numbers of effective antibiotics left in the arsenal.
The researchers warn that if the problem isn’t addressed and people don’t take their antibiotics as directed that gonorrhea could emerge as a very nasty infection. And that’s nothing to clap about!
And now that we’ve had our horror stories for the week, let’s turn to something a little more benign. Let’s head off for ancient Rome for some surprising modern-day news.
WHERE DID HE COME FROM?
Researchers excavating an ancient Roman cemetery recently made a surprising discovery when they extracted ancient DNA from one of the skeletons buried at the site. They discovered two very interesting things. The bones were 2,000-years old and they weren’t Roman. The gentleman they belonged to was from a country far, far away. He was from Eastern Asia.
According to Tracy Prowse, assistant professor of Anthropology, and the lead author on the study, the evidence indicates that the subject was not born in the area around Vagnari the site of the cemetery. Based on her work in the region, she thinks the East Asian man, who lived sometime between the first to second centuries AD — the early Roman Empire — was a slave or worker on the site. His surviving grave goods consist of a single pot (which archaeologists used to date the burial). What’s more, his burial was disturbed in antiquity and someone was buried on top of him.
Prowse’s team can’t say how recently he, or his ancestors, left East Asia: he could have made the journey alone, or his East Asian genes might have come from a distant maternal ancestor. But the evidence indicates that he was definitely not born in Italy and likely came here from elsewhere in the Roman Empire.
During this era, Vagnari was an Imperial estate owned by the emperor in Rome and controlled by a local administrator. Workers were employed in industrial activities on the site, including iron smelting and tile production. These tiles were used for roofing buildings on the site and were also used as grave covers for the people buried in the cemetery. Fragmentary tiles found in and around Vagnari are marked "Gratus Caesaris," which translates as "slave of the emperor."
Although this man was probably a slave, his DNA tells us that he was born far beyond the borders of the Roman empire at that time. It also probably tells us that people of that time were wanderers just like they are today. And now, another interesting cemetery discovery from ancient Rome.
The grave of a mystery man. (Credit: Image courtesy of McMaster University)
AND DO WE WANT TO LET HIM OUT?
If the previous story leaves us with a mystery about where the man came from, there is more grave news from Rome. In the ruins of a city that was once Rome’s neighbor, archaeologists have found a 1,000-pound lead coffin.
Who or what is inside is still a mystery, said Nicola Terrenato, the University of Michigan professor of classical studies who leads the project — the largest American dig in Italy in the past 50 years. The sarcophagus will soon be transported to the American Academy in Rome, where engineers will use heating techniques and tiny cameras in an effort to gain insights about the contents without breaking the coffin itself.
"We’re very excited about this find," Terrenato said. "Romans as a rule weren’t buried in coffins to begin with and when they did use coffins, they were mostly wooden. There are only a handful of other examples from Italy of lead coffins from this age — the second, third or fourth century A.D. We know of virtually no others in this region."
And this coffin is especially unusual because of its size. It’s made from a sheet of lead that’s an inch thick and folded onto itself an inch thick. A thousand pounds of lead represented an enormous amount of wealth in ancient Roman times and the researchers are mystified as to why so much of it would be used in a burial.
Human remains encased in lead coffins tend to be well preserved, if difficult to get to but the researchers want to avoid breaking into the coffin because the amount of force necessary to break through the lead would likely damage the contents. Instead, they will first use thermography and endoscopy.
Thermography involves heating the coffin a few degrees and monitoring the resulting thermal response. Bones and any artifacts buried with them would have different thermal responses. Endoscopy involves inserting a miniature l camera through a small hole bored into the coffin. But how well that works depends on how much dirt has found its way into the container over the centuries. The researchers could also do an MRI scan, but that would require hauling the half-ton casket to a hospital.
Was the deceased a soldier? A gladiator? A bishop? All are possibilities, some more remote than others. The researchers will do their best to examine the bones and any "grave goods" or Christian symbols inside the container in an effort to make a determination.
The site of Gabii, situated on undeveloped land 11 miles east of Rome in modern-day Lazio, was a major city that pre-dates Rome but seems to have waned as the Roman Empire grew. Studying Gabii gives
researchers a glimpse into pre-Roman life and offers clues to how early Italian cities formed. It also allows them easier access to more substantial archaeological layers or strata. In the city of Rome, layers of civilization were built on top of each other, and archaeologists are not able or allowed to disturb them. The researchers hope to find many things at Gabii, not just a mysterious coffin
The lead coffin archaeologists found in the abandoned ancient city of Gabii, Italy could contain a gladiator or bishop. (Credit: Image courtesy of University of Michigan)
Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.
Well, my office is about to be taken over by the bulging medical files, so it’s off we go into a little excursion into what ails us. There’s good news and there’s bad news and today we’re considering some diseases that ail us specifically here in the Marianas. And of course, the disease that’s on the upswing with all that good food all over the world is diabetes.
GETTING AT THE ROOT
Scientists have known for quite some time that babies with low birth weights have an increased risk of developing type 2 diabetes as adults. This is usually attributed to malnutrition of the mother during pregnancy, but German scientists have done some data analysis and discovered that genetic background may also play a major role. They analyzed the data of 729 children whose mothers had type 1 diabetes and who thus had a higher diabetes risk.
The scientists investigated the genetic background of fetuses for alterations in individual DNA bases. They focused on three gene regions that are known to be involved in diabetes caused by reduced insulin secretion and looked at them in relation to birth weight. They discovered that two of the regions had a significant association with low birth weights in the infants. This implies that there may be a genetic cause for both low birth weights and the development of diabetes later in life.
With their findings, the German researchers have come a step closer to understanding the underlying genetic mechanisms of diabetes diseases. Their next investigation will be to see if the gene regions examined in the study also have an effect on body weight later in life. Since their study has run continuously since 1989, this data already exists and simply needs to be analyzed.
So, it appears that genetic factors can cause both low birth weights and diabetes later in life. But where are the diabetics? Well, we know that there are many in the Marianas, and that diabetes is becoming more prevalent in the mainland US, but that’s not where most diabetics are and their location may surprise you.
WHERE THE PROBLEM LIES
A large population-based study of diabetes conducted by investigators from Tulane University and their Chinese colleagues has concluded that the disease has reached epidemic proportions in the adult population of China. The study estimates that 92.4 million adults age 20 or older (9.7 percent of the population) have diabetes and 148.2 million adults (15.5 percent) have prediabetes, a key risk factor for the development of overt diabetes and cardiovascular disease. (This compares with 7.8 percent of the United States population).
The study builds on several recent large studies in China that have documented a rapid increase in diabetes in the population. The current study administered an oral glucose tolerance test to 46,239 adults aged 20 or older from 14 provinces and municipalities throughout China in order to identify cases of previously undiagnosed diabetes. Subjects of the study who had been previously diagnosed with diabetes were identified through questioning by the study’s data collectors.
Following recent rapid economic development in China, cardiovascular disease has become the leading cause of death in the county. Diabetes is a major risk factor for cardiovascular disease, and the prevalence of diabetes in China, as this study indicates, is high and increasing. Diabetes increases the risk of cardiovascular complications and premature death, and results in a massive economic burden for society.
The researchers noted a higher prevalence of diabetes among urban residents in China than among rural ones, a result consistent with observations that have been made in developing countries throughout the world. "Urbanization is associated with changes in lifestyle that lead to physical inactivity, an unhealthful diet and obesity, all of which have been implicated as contributing factors in the development of diabetes," says Dr. Jiang He, a professor at Tulane University and the senior author of the study.
With its very large population, China may bear a higher diabetes-related burden than any other country. Especially alarming is the finding that the majority of cases of diabetes (60.7 percent) are undiagnosed and untreated. The researchers conclude that diabetes and its consequences have become a major public health crisis in China, and recommend that the country quickly develop and institute national strategies for preventing, detecting and treating diabetes in the general population.
So, how do the Marianas stack up in the race no one wants to win? According to the most recent data, our population is right up there with China’s at between 9 and 10 percent diabetic.
How do you keep from being diabetic? Exercise more and eat less! All your life!! And stop drinking the sugared soft drinks. It couldn’t hurt! And here’s something else that couldn’t hurt.
AN OUNCE OF PREVENTION
So you want more advice on how to avoid diabetes and even heart disease? Start taking your vitamin D. According to a team of English researchers, middle aged and elderly people with high levels of vitamin D could reduce their chances of developing heart disease or diabetes by 43%.
Vitamin D is a fat-soluble vitamin that is naturally present in some foods and is also produced when ultraviolet rays from sunlight strike the skin and trigger vitamin D synthesis. Fish like salmon, tuna and mackerel are good sources of vitamin D, and it is also available as a dietary supplement.
Researchers looked at 28 studies with almost 100,000 participants. The people were from a variety of ethnic groups and the studies included both men and women. Half of the studies were conducted in the United States, eight were European, two studies were from Iran, three from Australasia and one from India.
The researchers discovered a significant association between high levels of vitamin D and a decreased risk of developing cardiovascular disease (33% reduction), type 2 diabetes (55% reduction) and metabolic syndrome (51% reduction).
So keep eating that fish and taking time for a little sunshine in your busy day. Your body will love you for it!
And now we turn our attention to another real problem here in the Marianas. It’s a real killer and it’s on the upswing everywhere. It’s tuberculosis.
FIGHTING THE BAD ONES
Tuberculosis is a nasty disease that can take many forms in the body. The bad news is that a bad disease takes bad drugs to kill it and they must be taken every single day over a long period of time. The real problem is that once people start to feel better, they stop taking their drugs early. Unfortunately, they haven’t killed the killer; they’ve done something infinitely worse. They’ve made it drug-resistant.
According to the World Health Organization in some areas of the world, one in four people with tuberculosis (TB) becomes ill with a form of the disease that can no longer be treated with standard drugs regimens. That’s right, folks, there’s TB out there that’s resistant to every drug on the planet.
Not only that. TB has another little trick up its sleeve. TB can affect you two ways. When people are infected with TB they can become sick immediately. But in many cases, the TB hides in your body and becomes inactive or latent. Unfortunately, NONE of the antibiotics used to fight TB are effective against latent TB. They only work when the disease becomes active. This is a major problem as ten percent of the people who have latent TB will develop the active disease at some point and become both sick and contagious.
A team of researchers from Australia has discovered a protein that’s essential for TB to survive and they’ve had some success in developing a drug that will inhibit that protein. They are currently doing studies to see just how effective the drug is against latent TB. If the project succeeds, it will be the first new treatment for TB since 1962.
This is exciting news given that TB kills almost 2 million people each year. One third of the world’s population, or two billion people, are infected with TB. Every second of every day another person is infected.
And like diabetes, this one is at our doorstep too. It has reared its ugly head in my very own family. But at least here, there’s no problem with people not taking their drugs. Public Health requires that you take your drugs in front of a nurse. Every single day. Diabetes and tuberculosis. Just two of the things that are poised to get you. Live healthy and you’ll live longer!
Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.
I’ve decided that it’s time to take a look at those other living things that share the planet with us. No, not the animals, we’ve visited them several times recently, and not the microbes even though technically we share the planet with them and not the other way around, but those living things without whom we would die very quickly. Stumped? They make your oxygen for you and without them you’d starve. We’d do just fine without the other animals, thank you, but your very existence depends on the plants.
We’ll start our journey into the photosynthetic part of the kingdom with a couple of stories about a plant that’s very important right here in the Marianas. Rice.
RICE IN TROUBLE
Huge floods in the Philippines, India’s delayed monsoon, and extensive drought in Australia all took their toll on last year’s rice crops, demonstrating the vulnerability of rice to extreme weather.
The magazine Rice Today (I bet you didn’t know there’s a whole magazine devoted to rice, did you?) recently focused on climate change and its potential impact on rice. They report that the International Rice Research Institute (IRRI) has mapped rice-growing regions in the Philippines that are most likely to experience the negative effects of climate change, showing the extent to which climate change threatens rice production.
Luckily for the rice eaters of the world, the IRRI has solutions to help farmers cope with climate change. Cyclone Nargis wreaked havoc on the country of Myanmar and its rice crops in 2008. Since then, IRRI has sent submergence-tolerant and salt-tolerant rice varieties for testing there as more resilient options for farmers.
Massive rat infestations in Myanmar followed cyclone Nargis and the rats have also been causing trouble in Laos and Bangladesh, where the rodents ate up to 100% of rice crops, invaded house stores of food and bit sleeping people.
The IRRI sponsored a Rice Genetics Symposium in the Philippines last year where scientists exchanged information about the latest rice genetics research. In California, rice growers are directly funding their own research to develop rice varieties suited to their conditions. The California growers are trying to meet the global shortfall aggravated by drought in Australia. In sub-Saharan Africa, rice growers are being guided by research to help them adopt suitable mechanization techniques to improve their production.
Rice is the second most cultivated starch after corn and it provides the bulk of the calorie intake for most of Asia. China and India are the world’s largest rice producers but most of their production is consumed ‘in-house’.
Unfortunately for the future, much rice is produced in river deltas that are prone to flooding and salt contamination if world sea levels rise.
BUT HELP IS ON THE WAY
Although more corn is produced than rice, rice actually feeds over half of the world’s population. Rice hasn’t changed as much in appearance from its wild counterparts as corn has, but it is domesticated rice that provides almost all the world’s rice crops. But domesticated rice is genetically static and it’s hard for the plant to adapt to changing growing conditions. There are traditional varieties of rice that are still genetically evolving. Researchers hope to tap into these traits to improve crops worldwide.
Scientists from Washington University in St. Louis and Chiang Mai University in Thailand are showing how natural genetic drift and the agricultural practices of traditional farmers combine to influence the genetic diversity of a given strain of rice.
The researchers studied a variety of rice grown by the Karen people in Thailand and compared the genetic variation among the same variety of rice grown in different fields and villages. They discovered that the varying genetic types of the rice population occurred (unsurprisingly) in much the same pattern as the genetic diversity of native plant species. The further apart the rice fields are, the more genetically distinct they are.
In the vast delta of the Chiang Mai river, farmers grow modern high-yield rice. In the hills, the Karen people practice traditional agriculture, growing ancestral varieties of rice with traditional practices. Expert farmers play a role in maintaining their crop’s genetic diversity by exchanging and choosing seeds to plant the following year.
The researchers discovered that one farmer had had a genetic mutation in one of his fields. One of the rice plants produced a purple head. He was very curious and removed the seeds to grow in an isolated area because he wanted to see what it looked like and tasted like. The researchers said this was probably how humans domesticated plants, smart people were making smart choices in what to plant and grow.
Most of today’s crops have been genetically optimized to consistently give large yields. Seeds are purchased from a supplier and the plants are all genetically similar. They may be extraordinarily important in feeding the world, but their genetic sameness leaves them vulnerable to change.
The rice grown by the Karen people is genetically dynamic, because of genetic drift and the farmer’s artificial selection. Each year, the farmers choose the seeds that grow best in their fields, which may differ in soil type, elevation, and temperature from other fields. Their crops are constantly evolving in response to local conditions.
Although most agriculture in the United States for instance, focuses on growing high-yield crops to produce food for people living in cities, varieties of corn and other crops exist in seed banks.
The Hopi Indians in Arizona are also beginning to concentrate on growing their native varieties of corn. These varieties are important because they’re adapted to hot and dry conditions, something that will become more prevalent as the climate warms.
So here’s to the Karens and the Hopis. Their traditional ways may keep all of us from starving later on!
Traditional varieties of rice provide a genetically evolving pool of traits that can be tapped to improve crops worldwide, a new study suggests. (Credit: National Science Foundation)
So . . . . if we lose rice and we lose corn, what are we going to eat? Hang in there! Help is just around the corner, in a very unexpected form.
JUST EAT THE WEEDS
Anyone who has ever made a trip to the southeastern United States definitely noticed all those vines that hang all over everything. That’s kudzu, a vining member of the pea family that has been called “The vine that ate the South”
Kudzu has overgrown almost 10 million acres in the southeastern United States, but researchers in Alabama and Iowa are reporting the first evidence that root extracts from kudzu show promise as a dietary supplement for a high-risk condition, metabolic syndrome, the ‘fat disease’ that affects almost 50 million people in the United States alone.
People with metabolic syndrome are obese, have high blood pressure and high cholesterol, and problems with their body’s ability to use insulin. Those disorders mean a high risk for heart attacks, strokes, and other diseases. Researchers have been seeking natural substances to treat metabolic syndrome. The current study evaluated kudzu root extracts, which contain healthful substances called isoflavones.
An excessive amount of glucose in the blood is linked to both diabetes and obesity. An extract from kudzu roots called puerarin (the plant’s scientific name is Pueraria lobata) seems to regulate glucose by steering it to places where it’s needed, like muscles, and away from fat cells and blood vessels.
The study found that a kudzu root extract had beneficial effects on lab rats used in a study on the causes and control of metabolic syndrome. After two months of taking the extract, the rats had lower cholesterol, blood pressure, blood sugar, and insulin levels that a control group not given the extract. Although more work remains to be done (as always!) kudzu root just could be a magic bullet for metabolic syndrome and go from “The plant that ate to the South” to “The plant that made us healthy”!
Kudzu, a nuisance vine, shows promise as a dietary supplement that fights an unhealthy condition called metabolic syndrome. (Credit: Wikimedia Commons)
One wonders what miracles lie in the roots of tangan-tangan or Kadena de Amor? Of course, I’ve been saying for years that there’s a very simple way to deal with our brown tree snake problem. Just convince the Chinese and other Asians that some part of the snake (extraction of which involves killing it) is a powerful human aphrodisiac. Voila! No more snake problem!
Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.
Well, there’s one file drawer that I’m been seriously avoiding, because all the news in it is bad, but it’s another stunningly beautiful day on Guam and I think we can handle it. So let’s go have a look at the latest on global warming. Our first story gives you some really good ideas about where NOT to buy property!
THE BIG BOYS WEIGH IN
Scientists at Princeton and Harvard have carried out an analysis of the geologic record of global sea levels and reached some very troubling conclusions. Their novel statistical approach shows that our planet’s polar ice sheets are vulnerable to large-scale melting even if it doesn’t get much warmer. This melting would lead to a large and relatively rapid rise in global sea levels.
According to the analysis, an additional 2 degrees of global warming could cause a long term sea level rise of 20 to 30 feet. If sea levels rise this much, say goodbye to New Orleans, most of southern Florida, Bangladesh, most of the Netherlands and (and this is the REALLY bad part) virtually every port city in the world.
As part of their study, the researchers compiled an extensive database of geological sea level indicators for a period known as the last interglacial stage about 125,000 years ago. Polar temperatures during this stage were likely 5 to 10 degrees F. warmer than today.
Previous geological studies of sea level benchmarks like as coral reefs and beaches had shown that in many places local sea levels during the last interglacial stage were higher than today. But sea levels during an ice age can also change because all that ice deforms the land. Therefore it’s hard to determine global sea levels from local levels unless you have a really big data base and understand how massive quantities of ice (and their disappearance) can change things. You also need to be able to integrate all that data. (Luckily, if you’re from Harvard and Princeton, you have that at your disposal.)
The researchers determined there’s a 95 percent probability that in the last interglacial stage, global sea level peaked somewhere between 25 and 30 feet above its present level. They also determined that during the last interglacial it was slightly warmer than current temperature levels. They also found that global sea levels rose for centuries at least two to three times faster than the current rate, and that both the Greenland and West Antarctic ice sheet likely shrank significantly and made important contributions to sea level rise.
So, Harvard and Princeton scientists probably aren’t buying property in New Orleans or New York or Miami or Agana. Twenty-five to thirty feet. And don’t go making plans to travel to Honolulu. Not only are their port facilities underwater in a 25 foot sea level rise, so is their airport. Not good in an island economy where almost everything is imported! Say, do any of you readers have anything to do with the port? Could we maybe put all those cranes on wheels so we can just drive them to higher ground?
So, they say this was what it was like in the last interglacial, but what’s happening up there (and down there) right now?
WARMER WATER EVERYWHERE
Well, for one thing, it turns out that we’re exporting our warm water north and unfortunately for the port cities (and the planet) subtropical waters are reaching Greenland’s glaciers, driving melting and triggering an acceleration of ice loss.
A team of researchers led by Fiamma Straneo, a physical oceanographer from the Woods Hole Oceanographic Institution (WHOI) have been exploring the area around Greenland and Straneo says, “This is the first time we’ve seen waters this warm in any of the fjords in Greenland. The subtropical waters are flowing through the fjord very quickly, so they can transport heat and drive melting at the end of the glacier.”
Greenland’s ice sheet, which is two-miles thick and covers an area about the size of Mexico, has lost mass at an accelerated rate over the last decade. The ice sheet’s contribution to sea level rise during that time frame doubled due to increased melting and, to a greater extent, the widespread acceleration of outlet glaciers around Greenland.
While melting due to warming air temperatures is a known event, scientists are just beginning to learn more about the ocean’s impact — in particular, the influence of currents — on the ice sheet.
“Among the mechanisms that we suspected might be triggering this acceleration are recent changes in ocean circulation in the North Atlantic, which are delivering larger amounts of subtropical waters to the high latitudes,” says Straneo. But a lack of observations and measurements from Greenland’s glaciers prior to the acceleration made it difficult to confirm.
The research team, which included colleagues from University of Maine, conducted two extensive surveys collecting both ship-based and moored oceanographic data from Sermilik Fjord — a large glacial fjord in East Greenland. Sermilik Fjord, which is about 65 miles long, connects Helheim Glacier with the Irminger Sea. In 2003 alone, Helheim Glacier retreated several kilometers and almost doubled its flow speed.
Deep inside the Sermilik Fjord, researchers found subtropical water as warm as 39 degrees F. The team also enlisted the help of a novel team of researchers. They used data collected by 19 hooded seals tagged with satellite-linked temperature depth-recorders. Their data revealed that the water warms from July to December, and that subtropical waters are present on the shelf year round. (Although I confess that I’m having a little trouble calling 39 degree water ’subtropical’!)
“This is the first extensive survey of one of these fjords that shows us how these warm waters circulate and how vigorous the circulation is,” says Straneo. “Changes in the large-scale ocean circulation of the North Atlantic are propagating to the glaciers very quickly — not in a matter of years, but a matter of months. It’s a very rapid communication.”
Straneo also adds that the study highlights how little is known about ocean-glacier interactions. How these warm water currents interact with the coastal ice is a connection not currently included in climate models.
Recent changes in ocean circulation in the North Atlantic are delivering larger amounts of subtropical waters to the high latitudes. Melting ice also means more fresh water in the ocean, which could flood into the North Atlantic and disrupt a global system of currents, known as the Ocean Conveyor. (Credit: Jack Cook, Woods Hole Oceanographic Institution)
If the North Pole ice cap melts it won’t contribute much to sea level rise because that ice is already in the water and as we all know nine tenths of an iceberg is already IN the water so if it melts only the remaining tenth contributes to sea level rise. The ice that covers Greenland is a problem, of course, but Greenland is only the size of Mexico. The real ice champion is, of course, Antarctica. So, what’s going on at the bottom of the world? And as you suspected, the news is NOT good.
WARMING WARMING EVERYWHERE
Ice shelves are retreating on the Antarctic Peninsula due to climate change, according to new data. This could result in glacier retreat and sea-level rise if warming continues, threatening coastal communities and low-lying islands worldwide, experts say. (Hmmm where have we heard this before?)
Research by the U.S. Geological Survey is the first to document that every ice front in the southern part of the Antarctic Peninsula has been retreating overall from 1947 to 2009, with the most dramatic changes occurring since 1990.
The ice shelves are attached to the continent and already floating, (good news!) These ice shelves, however, are the last ramparts that hold the Antarctic ice sheet in place. You know the Antarctic ice sheet. It covers about 98 percent of the Antarctic continent. As the ice shelves break off and become free-floating ice bergs, it’s easier for outlet glaciers and ice streams from the ice sheet to flow into the sea. (BAD news!)
The Antarctic Peninsula is the ‘hook’ of land (ice?) that reaches up toward South America and it’s one of Antarctica’s most rapidly changing areas because it’s farthest away from the South Pole. Its ice shelf loss may be a forecast of changes in other parts of Antarctica and the world if warming continues.
Ice retreat along the southern part of the Peninsula is of particular interest because that area has the Peninsula’s coldest temperatures and it shows that global warming is affecting the Peninsula’s entire length.
The Antarctic Peninsula’s southern section contains five major ice shelves: Wilkins, George VI, Bach, Stange and the southern portion of Larsen Ice Shelf. The ice lost since 1998 from the Wilkins Ice Shelf alone totals more than 4,000 square kilometers, an area larger than the state of Rhode Island and the Larsen Ice Shelf has also sustained major ice loss.
This image shows ice-front retreat in part of the southern Antarctic Peninsula from 1947 to 2009. USGS scientists are studying coastal and glacier change along the entire Antarctic coastline. The southern portion of the Antarctic Peninsula is one area studied as part of this project, and is summarized in the USGS report, “Coastal-Change and Glaciological Map of the Palmer Land Area, Antarctica: 1947–2009″ (Credit: Image courtesy of U.S. Geological Survey)
Oh, and did I mention that there’s data (mindful of that erupting volcano in Iceland) that some of the mountains buried under miles of ice in Antarctica are actually ACTIVE volcanoes? What melting fun if one of them erupts!
Jim is, above all, a passionate eco-humanitarian who has developed his own science talk-radio show to inform The DEEP’s listeners about such newsy topics as global warming, shark-finning and reef protection as well as to explore earth’s many underwater and space mysteries.
sailing 12,000 miles and visiting five countries Jim is back here, ready to explore the depths of the ocean to the deepest frontier, space MORE>>
Lady Pam Eastlick is an expert in both the stars
and seas as a graduate of the University of Guam Marine
Lab and the Director of the UOG Planetarium.