Other Fish in the Sea

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<figcaption>The meaning of the word "bichir" (pronounced "be-SHEER"), the name African fishermen have used for this fish since the early 19th century, is obscure.
        
        <div class="credit">© PhotoVault</div>
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<h3>Bichir</h3><p>Bichir are the only living fossil fish commonly kept as pets.</p><p>Bichir are bottom-dwelling freshwater fish native to western Africa. They are among the most primitive of the ray-finned fish, the dominant group of modern fish, which arose about 395 million years ago. A bichir's long, narrow body is commonly two to three feet long and covered with thick, diamond-shaped scales made of a shiny enamel-like substance called ganoine. Such scales were also present in the earliest ray-finned fish and are different from those of other living fish, except gar.</p><p>Like many of the other living fossil fish, the bichir is especially adapted to life in dry environments. Instead of a regular swim bladder it has a pair of modified "lungs," like those of the lungfish, which enable it to survive out of water for several hours.</p>
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<figcaption>The main predator of bowfin are bigger bowfin.
        
        <div class="credit">© Shedd Aquarium</div>
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<h3>Bowfin</h3><p>Bowfin are normally ravenous eaters but they can go without eating longer than any other fish—for nearly a year if necessary—because of their low metabolisms.</p><p>There is only one living species of bowfin, which is also called the dogfish, mudfish, or grindle. This uniquely American freshwater fish is found in the Mississippi River basin, the Great Lakes, and other small bodies of water east of the Great Lakes. It is a fierce fighter with sharp teeth that is known to eat fish of all kinds as well as frogs, snakes, turtles, and even small mammals. It also sometimes cannibalizes other bowfin. Bowfin do not make good eating but are considered good game fish.</p><p>Bowfin can use their swim bladders, which most other fish use as a kind of flotation device, as a lung, allowing them to survive out of water for up to a day. In oxygen-poor water, bowfin will often gulp surface air in order to breathe. Paleontologists have discovered fossilized bowfin from North America, South America, Europe, Africa, and Asia, the earliest of which dates to the Jurassic Era, which began 213 million years ago.</p><p><br/></p>
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<figcaption>A needle-nosed gar caught from the Pecos River near Carlsbad, New Mexico.
        
        <div class="credit">© Shedd Aquarium</div>
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<h3>Gar</h3><p>Gar eggs are lethally toxic to humans and other warm-blooded vertebrates.</p><p>Gar (named for the Anglo-Saxon word for "spear") are freshwater fish found in the warmer rivers and lakes of the southern U.S., Central America, Mexico, and the West Indies. They are highly predaceous, with long jaws and large, sharp teeth. They will attack any fish in their path, lying perfectly still until they sense potential prey, then striking and taking a "victory lap" or two around their kill. Fishermen consider them a nuisance because they destroy many fish, sometimes without bothering to eat them; they are also inedible.</p><p>Gar sport a fierce-looking armature of plate-like scales shaped like diamonds, which are made of inorganic salt, like those of many now-extinct fish. Like other primitive fish, the gar has a swim bladder connected to its esophagus, which can be used for breathing.</p>
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<figcaption>Hagfish are popular in South Korea, where almost five million pounds of their meat is consumed every year.
        
        <div class="credit">© Shedd Aquarium</div>
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<h3>Hagfish</h3><p>The hagfish is the only vertebrate whose body fluids are the same concentration as the surrounding seawater.</p><p>It is easy to see how this mud-dwelling, eel-like fish named for its hideous appearance has been overshadowed by the comparatively comely coelacanth. Also known as slime eels, hagfish are indigenous to both the Atlantic and Pacific oceans, where they live at depths of 100 to 3,150 feet.</p><p>Eyeless, jawless, and dependent on their sense of smell to find food, hagfish invade feeble or dead fish by entering through their mouths and settling in their stomachs, where they secrete a slimy substance that protects them from the digestive juices of their hosts. They then eat their hosts from the inside out. Because hagfish are soft-bodied, it has been difficult for scientists to find and interpret evidence of their existence in the fossil record. They believe, however, that this vertebrate's nearly identical ancestor arose more than 550 million years ago, in the Precambrian Era.</p><p><br/></p>
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<figcaption>A lamprey can kill as much as 40 pounds of fish during the 12 to 20 months of its adult life.
        
        <div class="credit">© Shedd Aquarium</div>
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<h3>Lamprey</h3><p>King Henry I of England died in Normandy in 1135 after gorging himself on his favorite food: boiled lampreys.</p><p>Like hagfish, lampreys belong to the jawless fish, the most primitive of all fish. Adult lampreys have a notochord, a backbone-like structure that more-evolved vertebrates lose after the embryonic stage.</p><p>Lampreys live in both freshwater and marine environments worldwide, usually migrating from saltwater to freshwater to spawn. Some sea lamprey populations have become landlocked and represent serious pests to fishing industries. Adult lampreys parasitically attach themselves to other fish, sucking out their body fluids after scratching a hole with their sandpapery tongues. Lampreys have an anticoagulant in their saliva that keeps the blood of their host fluid, and some lampreys eat flesh as well. Their unwilling hosts may eventually die.</p>
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<figcaption>The Queensland lungfish inhabits the rivers of southeastern Queensland, Australia.
        
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<h3>Lungfish</h3><p>The lungfish is the only living fossil fish to have a rock band named after it.</p><p>The first living lungfish was discovered in the 1830s, almost a century before the coelacanth appeared. Like the coelacanth, this fish was previously thought to be extinct, because it was known only from fossilized Devonian-Period remains almost 450 million years old.</p><p>The "lungs" of the lungfish are similar to those of land animals. They are modified swim bladders, which most fish use for buoyancy while swimming. Lungfish use theirs to absorb and conserve oxygen from air. Modern lungfish, which are found in rivers and swamps in Africa, South America, and Australia, can remain alive out of water by using their swim bladders like lungs. They are so adapted to living out of water that some species will drown if they are deprived of air.</p><p>Scientists believe lungfish are the closest living relatives of tetrapods—four-legged animals—with which they share a number of important characteristics, including tooth enamel; the arrangement of some skull bones; a separation of pulmonary-system blood flow from blood flow throughout the rest of the body; and four similarly sized limbs that have the same position and structure as tetrapod legs.</p>
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<figcaption>Paddlefish roe are important to the caviar business; indeed, much of the caviar sold as sturgeon roe is actually paddlefish roe.
        
        <div class="credit">© Shedd Aquarium</div>
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<h3>Paddlefish</h3><p>Spanish explorer Hernando de Soto discovered the paddlefish while exploring the Mississippi River in the 16th century.</p><p>There are only two species of paddlefish, which are defined by their large, paddle-shaped snouts. One is found in the Mississippi and the other in China's Yangtze River. Scientists once thought that these fish used their paddles to dig in muddy river bottoms or as a means of providing balance in river currents. The paddle, though, is used to gather sensory data, such as smells, tastes, and the electrical fields given off by other fish and prey. Oddly enough, adult paddlefish missing all or part of their paddle have no trouble surviving.</p><p>Paddlefish are large, reaching up to 15 feet in length as adults. They feed on crustaceans, and humans feed on them. North American paddlefish used to reach weights of 300 pounds, but the species has been overfished and now 100-pound paddlefish are considered large. Unlike most modern fish, paddlefish have skins with few scales, skeletons made almost wholly out of cartilage, and upturned tail fins like those of sturgeon and sharks.</p><p></p>
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<figcaption>The white sturgeon, native to the Pacific Ocean along the U.S. coastline and the rivers of northern California, is on the U.S. Endangered Species List.
        
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<h3>Sturgeon</h3><p>The sturgeon is the largest freshwater fish in the world.</p><p>There are 24 species of sturgeon worldwide, the most famous of which is the beluga sturgeon of the Caspian Sea, prized for its caviar. Found in fresh and salt waters in the Northern Hemisphere, the sturgeon is a bizarre-looking creature whose retractable mouth can be projected like a miniature elephant trunk from the underside of its head and whose body is armored with rows of thick plates. An adult Pacific sturgeon can weigh 400 pounds and reach more than 20 feet in length. These fish can live well over 100 years.</p><p>In addition to their armored appearance, sturgeon have several characteristics that are not found in modern fish and that mark them as ancient. Though most modern bony fish have symmetrical tails (the top and bottom lobes are the same size), sturgeon have asymmetric tails like those of a shark. They also have notochords, lack scales, and, like sharks, have spiral valves in their guts instead of intestines.</p>

<p>The coelacanth gets all the attention, but there are other &quot;fossil fish&quot; just as fascinating.</p>

Accidental Discoveries

<h3>
	Fortuitous accidents</h3>
<p>
	Accidents in medicine: The idea sends chills down your spine as you conjure up thoughts of misdiagnoses, mistakenly prescribed drugs, and wrongly amputated limbs. Yet while accidents in the examining room or on the operating table can be regrettable, even tragic, those that occur in the laboratory can sometimes lead to spectacular advances, life-saving treatments, and Nobel Prizes.</p>
<p>
	A seemingly insignificant finding by one researcher leads to a breakthrough discovery by another; a physician methodically pursuing the answer to a medical conundrum over many years suddenly has a "Eureka" moment; a scientist who chooses to study a contaminant in his culture rather than tossing it out stumbles upon something entirely new. Consider the following historic cases:</p>
<h3>
	Quinine</h3>
<p>
	The story behind the chance discovery of the anti-malarial drug quinine may be more legend than fact, but it is nevertheless a story worthy of note. The account that has gained the most currency credits a South American Indian with being the first to find a medical application for quinine. According to legend, the man unwittingly ingested quinine while suffering a malarial fever in a jungle high in the Andes. Needing desperately to quench his thirst, he drank his fill from a small, bitter-tasting pool of water. Nearby stood one or more varieties of cinchona, which grows from Colombia to Bolivia on humid slopes above 5,000 feet. The bark of the cinchona, which the indigenous people knew as <i>quina-quina,</i> was thought to be poisonous. But when this man's fever miraculously abated, he brought news of the medicinal tree back to his tribe, which began to use its bark to treat malaria.</p>
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<img alt="Bark of cinchona tree" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/accidental-discoveries-01.width-990_xbLGGKG.jpg"/>
<figcaption>A laborer scrapes the bark from a cinchona tree. The bark is then sundried and pulverized to make the drug quinine.
        
        <div class="credit">Corbis</div>
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<p>
	Since the first officially noted use of quinine to fight malaria occurred in a community of Jesuit missionaries in Lima, Peru in 1630, historians have surmised that Indian tribes taught the missionaries how to extract the chemical quinine from cinchona bark. In any case, the Jesuits' use of quinine as a malaria medication was the first documented use of a chemical compound to successfully treat an infectious disease. To this day, quinine-based anti-malarials are widely used as effective treatments against the growth and reproduction of malarial parasites in humans.</p>
<h3>
	Smallpox vaccination</h3>
<p>
	In 1796, Edward Jenner, a British scientist and surgeon, had a brainstorm that ultimately led to the development of the first vaccine. A young milkmaid had told him how people who contracted cowpox, a harmless disease easily picked up during contact with cows, never got smallpox, a deadly scourge.</p>
<p>
	With this in mind, Jenner took samples from the open cowpox sores on the hands of a young dairymaid named Sarah Nelmes and inoculated eight-year-old James Phipps with pus he extracted from Nelmes' sores. (Experimenting on a child would be anathema today, but this was the 18<sup>th</sup> century.) The boy developed a slight fever and a few lesions but remained for the most part unscathed. A few months later, Jenner gave the boy another injection, this one containing smallpox. James failed to develop the disease, and the idea behind the modern vaccine was born.</p>
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<img alt="painting of Edward Jenner vaccine" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/accidental-discoveries-02.width-990_V6q8CpV.jpg"/>
<figcaption>A depiction of Edward Jenner vaccinating James Phipps, a boy of eight, on May 14, 1796
        
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<p>
	Though doctors and scientists would not begin to understand the biological basis of immunity for at least 50 years after Jenner's first inoculation, the technique of vaccinating against smallpox using the human strain of cowpox soon became a common and effective practice worldwide.</p>
<h3>
	X-Rays</h3>
<p>
	X-rays have become an important tool for medical diagnoses, but their discovery in 1895 by the German physicist Wilhelm Conrad Ríntgen had little to do with medical experimentation. Ríntgen was studying cathode rays, the phosphorescent stream of electrons used today in everything from televisions to fluorescent light bulbs. One earlier scientist had found that cathode rays can penetrate thin pieces of metal, while another showed that these rays could light up a fluorescent screen placed an inch or two away from a thin aluminum "window" in the glass tube.</p>
<p>
	Ríntgen wanted to determine if he could see cathode rays escaping from a glass tube completely covered with black cardboard. While performing this experiment, Ríntgen noticed that a glow appeared in his darkened laboratory several feet away from his cardboard-covered glass tube. At first he thought a tear in the paper sheathing was allowing light from the high-voltage coil inside the cathode-ray tube to escape. But he soon realized he had happened upon something entirely different. Rays of light were passing right through the thick paper and appearing on a fluorescent screen over a yard away.</p>
<p>
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<img alt="Wilhelm Conrad Rontgen" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/accidental-discoveries-03.width-990_TV7sczp.jpg"/>
<figcaption>Physicist Wilhelm Conrad Rí¶ntgen (1845-1923), discoverer of the X-ray
        
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<p>
	Ríntgen found that this new ray, which had many characteristics different from the cathode ray he had been studying, could penetrate solids and even record the image of a human skeleton on a photographic negative. In 1901, the first year of the Nobel Prize, Ríntgen won for his accidental discovery of what he called the "X-ray," which physicians worldwide soon adopted as a standard medical tool.</p>
<h3>
	Allergy</h3>
<p>
	Charles Robert Richet, a French physiologist, made several experiments testing the reaction of dogs exposed to poison from the tentacles of sea anemones. Some of the dogs died from allergic shock, but others survived their reactions and made full recoveries.</p>
<p>
	Weeks later, because the recovered dogs seemed completely normal, Richet wasted no time in reusing them for more experiments. They were given another dose of anemone poison, this time much smaller than before. The first time the dogs' allergic symptoms, including vomiting, shock, loss of consciousness, and in some cases death, had taken several days to fully develop. But this time the dogs suffered such serious symptoms just minutes after Richet administered the poison.</p>
<p>
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<figcaption>Charles Robert Richet used poison from a sea anemone like this one in his experiments on allergies.
        
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<p>
	Though Richet was puzzled by what had happened, he realized he could not disregard the unexpected result of his experiment. Later, he noted that his eventual conclusions about the dogs' affliction were "not at all the result of deep thinking, but of a simple observation, almost accidental; so that I have had no other merit than that of not refusing to see the facts which presented themselves before me, completely evident."</p>
<p>
	Richet's conclusions from his findings came to form the theoretical basis of the medical study and treatment of allergies. He eventually proved that there was a physiological state called anaphylaxis that was the antithesis of prophylaxis: When an allergic subject is exposed to an allergen a second time, he or she is even more sensitive to its effects than the first time. Instead of building immunity to the substance through exposure (prophylaxis), the allergic subject's immunity becomes greatly reduced.</p>
<p>
	In 1913 Richet received a Nobel Prize for his discovery and articulation of diseases of allergy.</p>
<h3>
	Insulin</h3>
<p>
	Frederick G. Banting, a young Canadian doctor, and Professor John J.R. MacLeod of the University of Toronto shared a Nobel Prize in 1923 for their isolation and clinical use of insulin against diabetes. Their work with insulin followed from the chance discovery of the link between the pancreas and blood-sugar levels by two other doctors on the other side of the Atlantic decades earlier.</p>
<p>
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<img alt="Frederick Banting" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/accidental-discoveries-05.width-990_iQbreSv.jpg"/>
<figcaption>Frederick Banting (left) and John MacLeod discovered insulin, the elusive substance that regulates blood-sugar levels in the body.
        
        <div class="credit">Corbis</div>
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<p>
	In 1889, German physicians Joseph von Mering and Oscar Minkowski removed the pancreas from a healthy dog in order to study the role of the pancreas in digestion. Several days after the dog's pancreas was removed, the doctors happened to notice a swarm of flies feeding on a puddle of the dog's urine. On testing the urine to determine the cause of the flies' attraction, the doctors realized that the dog was secreting sugar in its urine, a sign of diabetes. Because the dog had been healthy prior to the surgery, the doctors knew that they had created its diabetic condition by removing its pancreas and thus understood for the first time the relationship between the pancreas and diabetes.</p>
<p>
	With more tests, von Mering and Minkowski concluded that a healthy pancreas must secrete a substance that controls the metabolism of sugar in the body. Though many scientists tried in vain to isolate the particular substance released by the pancreas after the Germans' accidental discovery, it was Banting and MacLeod who established that the mysterious substance was insulin and began to put it to use as the first truly valuable means of controlling diabetes.</p>
<h3>
	Pap smear</h3>
<p>
	Dr. George Nicholas Papanicolaou's chance observation, while doing a genetic study, of cancer cells on a slide containing a specimen from a woman's uterus spawned the routine use of the so-called "Pap smear," a simple test that has saved millions of women from the ravages of uterine cancer.</p>
<p>
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<img alt="George N. Papanicolaou" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/accidental-discoveries-06.width-990_RUTj5zu.jpg"/>
<figcaption>Dr. George N. Papanicolaou, who devised the "Pap" smear test for cancer, examines a slide in his laboratory in 1958.
        
        <div class="credit">Corbis</div>
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<p>
	In 1923, Papanicolaou undertook a study of vaginal fluid in women, in hopes of observing cellular changes over the course of a menstrual cycle. In female guinea pigs, Papanicolaou had already noticed cell transformation and wanted to corroborate the phenomenon in human females. It happened that one of Papanicolaou's human subjects was suffering from uterine cancer.</p>
<p>
	Upon examination of a slide made from a smear of the patient's vaginal fluid, Papanicolaou was astonished to discover that abnormal cancer cells could be plainly observed under a microscope. "The first observation of cancer cells in the smear of the uterine cervix," he later wrote, "gave me one of the greatest thrills I ever experienced during my scientific career." Papanicolaou quickly realized that doctors could administer a simple test to gather a sample of vaginal fluid and test it for early signs of uterine and other cancers.</p>
<h3>
	Penicillin</h3>
<p>
	The identification of penicillium mold by Dr. Alexander Fleming in 1928 is one of the best-known stories of medical discovery, not only because of its accidental nature, but also because penicillin has remained one of the most important and useful drugs in our arsenal, and its discovery triggered invaluable research into a range of other invaluable antibiotic drugs.</p>
<p>
	While researching the flu in the summer of 1928, Dr. Fleming noticed that some mold had contaminated a flu culture in one of his petri dishes. Instead of throwing out the ruined dish, he decided to examine the moldy sample more closely.</p>
<p>
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<img alt="Penicillium mold" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/accidental-discoveries-07.width-990_R7Shz9d.jpg"/>
<figcaption>Penicillium mold (enlarged here many times) is a fungus that differs little from one that appears on bread in warm, humid weather.
        
        <div class="credit">Corbis</div>
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<p>
	Fleming had reaped the benefits of taking time to scrutinize contaminated samples before. In 1922, Fleming had accidentally shed one of his own tears into a bacteria sample and noticed that the spot where the tear had fallen was free of the bacteria that grew all around it. This discovery peaked his curiosity. After conducting some tests, he concluded that tears contain an antibiotic-like enzyme that could stave off minor bacterial growth.</p>
<p>
	Six years later, the mold Fleming observed in his petri dish reminded him of this first experience with a contaminated sample. The area surrounding the mold growing in the dish was clear, which told Fleming that the mold was lethal to the potent staphylococcus bacteria in the dish. Later he noted, "But for the previous experience, I would have thrown the plate away, as many bacteriologists have done before."</p>
<p>
	Instead, Fleming took the time to isolate the mold, eventually categorizing it as belonging to the genus <i>penicillium.</i> After many tests, Fleming realized that he had discovered a non-toxic antibiotic substance capable of killing many of the bacteria that cause minor and severe infections in humans and other animals. His work, which has saved countless lives, won him a Nobel Prize in 1945.</p>
<h3>
	Keep that mind open</h3>
<p>
	For all you would-be Nobel Prize-winners, remember the one trait that tied all these lucky strikers together: openmindedness. As the American physicist Joseph Henry once noted, "The seeds of great discoveries are constantly floating around us, but they only take root in minds well prepared to receive them."</p>

Some of medicine's most important treatments, including quinine, insulin, and penicillin, arose through serendipity.


The Final Eight Minutes

Annotated cockpit recordings reveal how the deadliest aviation disaster in history unfolded on March 27, 1977.
				

Miracle of Rice

<p>
	With at least a million children weakened by vitamin-A deficiency every year and an additional 350,000 going blind, the possibility that genetically engineered rice may soon be widely available in Asia and Africa makes rice seem nothing short of miraculous.</p>
<p>
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<figcaption>In the year 2000, annual production of rice worldwide was well over 400 million tons.
        
        <div class="credit">© Mark Gillow/iStockphoto</div>
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<h3>
	Origins</h3>
<p>
	A Malaysian aboriginal myth holds that all of the sky once lay flat on the Earth in the form of rice until the women of the tribe, wielding their long wooden rice brooms, heaved it upwards in the first harvest. From then on, rice fell back to Earth each year in time for a bountiful harvest.</p>
<p>
	Rice's evolutionary origins go far back into history, so far that scientists can only make intelligent guesses as to where the rice genus (<em>Oryza)</em> first grew. One theory maintains that rice arose in the ancient supercontinent known as Gondwana. Then, when Gondwana fragmented into Africa, South America, Antarctica, Australia/New Zealand, India, and Madagascar beginning about 200 million years ago, <em>Oryza</em> went with the fragments.</p>
<p>
	Rice, an annual grass belonging to the same family as barley, oats, rye, and wheat, grows today in a range of habitats almost unparalleled in the plant kingdom. It is cultivated in the cool Himalayan climates of Nepal and in the scorching deserts of Pakistan, Iran, and Egypt. In Latin America it grows as a dry-land crop, in Southeast Asia as a paddy crop watered by monsoon rains and floodwater. All told, some 358 million acres, or roughly 11 percent of the world's arable land, are given over to rice cultivation, according to the International Rice Research Institute (IRRI) in the Philippines.</p>
<p>
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<img alt="rice fields in Bali, Indonesia" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/miracle-rice-02.width-990_a3ddTyD.jpg"/>
<figcaption>Terraced rice fields in Bali, Indonesia. Farmers must incessantly weed such paddies to maintain water flow through the terraces.
        
        <div class="credit">© LP7/iStockphoto</div>
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<h3>
	Raising rice</h3>
<p>
	Rice-growing methods are almost as varied as the grain's geographical habitats. In the United States, farmers use highly mechanized systems, but in most developing nations, rice farming remains extremely labor-intensive. The work is backbreaking and relentless, and in Japan and other Asian countries where farmers tend terraced paddies, it is also muddy.</p>
<p>
	Paddy rice is irrigated by water diverted from rivers and mountain streams into a complex system of canals and riverways developed and perfected through centuries of use. Terracing, which requires constant maintenance, allows water to flow continuously down through successive rice fields (see <a href="http://www.pbs.org/wgbh/nova/satoyama/hillside.html">Build a Rice Paddy</a>). Farmers usually plant rice seed in a seedbed, then transplant young plants into the paddies, which have about six inches of water at this stage. As the plants mature, cultivators allow the water level in the field to drop. By the time the plants reach full maturity, the ground is entirely dry, and farmers can easily harvest the rice.</p>
<p>
	Harvesters cut the ripe grain from the stalk and then, after it has dried, thresh it to separate the grains from the so-called rice straw. In Asia, oxen typically do the threshing by trampling the rice laid out before them. Milling then removes each grain's hull to reveal the part of the rice plant that eventually ends up in our mouths. Milling both the hull and bran layers of the kernel renders so-called white rice; brown rice retains the bran. After the harvest, farmers turn over the soil, readying the paddy for another season.</p>
<p>
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<img alt="dried rice plant and rice grains" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/miracle-rice-03.width-990_vEWS3Gp.jpg"/>
<figcaption>Keeping the dried rice grains dry is key to their preservation.
        
        <div class="credit">© lamiel/iStockphoto</div>
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<p>
	The role rice plays in national culture varies dramatically depending on where you are. Most Americans, for example, view rice as just another commodity available on supermarket shelves. But in Japan, <em>o-kome,</em> or "honorable rice," is much more than a commodity. In the Shinto religion, sake, rice cakes, and other rice products are the most sacred of offerings, and to a nation that must import most of its meat, fish, and fruit, rice is a symbol of independence. Indeed, as a matter of tradition, the Japanese government strictly prohibits the import of rice as long as local crops provide harvests bountiful enough to satisfy the national appetite.</p>
<p>
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<img alt="rice flour in spoon" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/miracle-rice-04.width-990_IP6LABk.jpg"/>
<figcaption>In Japan, ground rice flour is the basis of everything from savory noodles to sweet <em>mochi</em> pastry.
        
        <div class="credit">© FotografiaBasica/iStockphoto</div>
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<p>
	Rice is the staple in many Asian countries besides Japan, and in the early 1960s it became apparent that the fast-growing Asian population would soon begin devouring rice at a far greater pace than it could produce it, leading to widespread famine.</p>
<p>
	The newly formed IRRI's solution to this potentially crippling pan-Asian problem was dramatic and far-reaching. It transformed the rice plant, eking out new varieties with built-in solutions to three main obstacles. First, the institute's researchers genetically reduced plant height from about five feet to roughly three feet. This change allowed farmers to douse rice plants with larger amounts of powdered fertilizer without causing their stalks to sag and even topple from the weight of increased panicles (clusters of grain). Second, they shortened the plant's growing period from about 160 days to 110, so that in warm climates, irrigation could supplement seasonal rainfall, and farmers could raise two or three crops every year instead of just one. Lastly, rice varieties were bred to be resistant to the most crippling diseases and insect pests. In most areas where these new varieties were sown, the results were—and continue to be—staggering. According to IRRI, from 1967 to 1992 during the so-called Green Revolution, the world's rice harvest doubled. In some countries such as Indonesia, the national rice harvest more than tripled.</p>
<p>
	But it's not over yet. Scientists have to reinvent the rice plant again in order to keep up with the still rapidly growing Asian population. The IRRI estimates that rice production must increase approximately 60 percent before the year 2020. One possible fine-tuning involves the addition of stalks to each plant (from about 15 to 25), allowing for more panicles per plant. The IRRI's Genetic Resources Center has a cold-storage unit that houses some 80,000 rice samples waiting to be crossbred into new varieties. The newest techniques in biotechnology and genetic engineering, which enable IRRI scientists to transfer the genes from one rice plant directly into the cells of another, reduce breeding time and allow for the transfer of specific traits. Instead of crossbreeding plants by hand in the field, scientists are now able to make finite genetic changes to plant embryos in test tubes, virtually ensuring the success of the transfer.</p>
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<img alt="variety of rice types in bowls" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/miracle-rice-05.width-990_7hncaA8.jpg"/>
<figcaption>Over centuries, agricultural techniques have lead to the cultivation of tens of thousands of rice varieties. Shown here are black wild rice, red wild rice, brown rice, mixed wild rice, green pandanus leaf flavored rice, red roselle flower flavored rice, and blue butterfly pea flower flavored rice.
        
        <div class="credit">© ShutterWorx/iStockphoto</div>
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<h3>
	A miracle's miracle</h3>
<p>
	Not surprisingly, the genetic manipulation of rice has become part of the increasingly polarized public debate about whether to welcome or ward off the addition of genetically modified foods into our diets. GM foods—so-called "Frankenfoods" in the minds of many people—made their commercial debut in the 1990s. Ever since, they have become the target of environmentalists and consumer advocates, who fear that genetically tinkering with the food we eat may have harmful repercussions for our health and the environment.</p>
<p>
	Specialists working on the rice plant would argue that the case of genetically engineered rice is different than that of other kinds of GM foods, such as mush-resistant bananas, self-fertilizing corn, and lettuce made unappealing to caterpillars. IRRI scientists have come up with Golden Rice, which is fortified with vitamin A and may benefit not just the wallets of the farmers who grow it but also the health of the consumers who eat it. This new rice, engineered to make its own supply of vitamin A (which gives the rice a golden color), could conceivably prevent blindness and even death among the developing world's poorest, most vitamin-A-deficient people. If that happened, it would be a miracle's miracle.</p>

Rice feeds the world. Explore the history and future of this indispensable grain, including its genetic engineering. 


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New regulations enacted after aviation disasters, such as this one involving a depleted fuel supply, help prevent future crashes.

Making Air Travel Safer

<div class="related"></div>
<p>Ironically, the very airplane crashes that give air travelers the most pause serve as the chief catalysts for increased safety, as most key improvements to flight protocols and equipment follow large-scale investigations into the most terrible disasters. In this overview, learn about a handful of major crashes that resulted in extensive inquiries and consequent changes. While safety experts caution that much still needs improvement—including reducing the more than 300 runway incursions that occur in the U.S. alone each year—these changes have made flying safer than ever.</p>
<p></p><h2>KLM Flight 4805 and Pan Am Flight 1736, March 27, 1977</h2><p>This crash remains the deadliest ever, claiming the lives of 583 people when two 747s collided on a foggy runway on the island of Tenerife in the Canary Islands. It occurred after a series of miscommunications between the two flight crews and Air Traffic Control. The KLM plane initiated takeoff while the Pan Am plane, unseen in the fog, was taxiing midway down the same runway. As the KLM plane began to lift off the tarmac, the lower part of its fuselage struck the upper fuselage of the Pan Am plane, which was in the process of turning off the runway. After Tenerife, officials made sweeping changes to international airline regulations, requiring that all control towers and flight crews worldwide use standardized English phrases. Also, cockpit procedures were modified so that the hierarchy among crew members was deemphasized and decision-making by mutual agreement was the rule. Known in the industry as "crew resource management," this modus operandi is now standard worldwide. (Watch NOVA's <a href="http://www.pbs.org/wgbh/nova/planecrash/">"Deadliest Plane Crash"</a>.)</p><h2>Avianca Flight 52 | January 25, 1990</h2><p>This Boeing 707 on service from Bogota, Colombia, crashed while approaching its destination at New York's JFK International Airport. Seventy-three of the 158 people aboard were killed. The accident occurred after the plane flew in a holding pattern for 77 minutes while awaiting landing clearance at JFK and ran out of fuel. The NTSB attributed the crash to the failure of the flight crew to manage the aircraft's fuel load and to communicate to ground controllers what had become an urgent fuel situation. The board also criticized the airline for failing to provide the crew with the latest wind shear information in New York, which could have helped the pilot anticipate landing delays there and plan for an alternative destination. The FAA subsequently mandated stricter flight planning and communication requirements for all foreign carriers operating in the U.S.</p><h2>USAir Flight 427 | September 8, 1994</h2><p>It took one of the longest air crash investigations in U.S. history to determine what happened (if not why) to cause this accident near Pittsburgh, Pennsylvania, which killed all 132 people aboard. En route from Chicago, the Boeing 737 went down in a wooded area 10 miles north of its destination at Greater Pittsburgh International Airport just seconds after the captain declared an emergency. In its final report released five years after the crash, the NTSB concluded that the aircraft's rudder, a moveable control surface hinged to the tail fin, became jammed for still unknown reasons, forcing the plane into an almost vertical roll at about 3,600 feet. NTSB recommendations prompted Boeing to completely redesign the 737's rudder control system and revise the aircraft's flight manual to include a procedural checklist for pilots faced with rudder-control problems.</p><p></p>
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<img alt="" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/making-air-travel-safer-02.width-990_ohA0T0B.jpg"/>
<figcaption>Following the investigation of American Eagle Flight 4184, all ATR-72s were retrofitted with additional de-icing equipment.
        
        <div class="credit">Courtesy of ATR Aircraft</div>
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<p></p><h2>American Eagle Flight 4184 | October 31, 1994</h2><p>Heavy air traffic and poor weather postponed the arrival of this flight at Chicago's O'Hare International Airport, where it was to have landed en route from Indianapolis, Indiana. The ATR-72, a twin-engine turboprop carrying 68 people, entered a holding pattern 65 miles southeast of O'Hare, which it maintained for over an hour in freezing rain. As the plane circled, a ridge of ice formed on the upper surface of its wings, eventually causing the aircraft's autopilot to suddenly disconnect and the pilots to lose control. The ATR disintegrated on impact with a field below, killing everyone aboard. Following an NTSB investigation, the FAA required that all ATR aircraft be fitted with expanded de-icing equipment. It also issued 18 "airworthiness directives" for all pilots operating small commuter aircraft, instructing them on how to recognize and respond to dangerous icing conditions.</p><h2>American Airlines Flight 965 | December 20, 1995</h2><p>Just 40 miles from its destination in Cali, Colombia, this nighttime flight from Miami, Florida, careened into the crest of an Andean mountain at about 8,900 feet, killing all but four of the 163 people aboard. Investigators identified a series of operational errors committed by the flight's two pilots. Their primary mistake was failure to correctly input heading instructions into an automated Flight Management System, which brought the airplane into an unfamiliar and dangerous landing approach. Furthermore, the inquiry found the 757's Ground Proximity Warning System to be inadequate. The investigation report introduced the issue of pilots' potential overreliance on automated flight systems and motivated the NTSB to make sweeping recommendations to address this problem. As a result, the FAA ordered most American-registered passenger aircraft to use an Early Ground Proximity Warning System to add redundancy in this area. It also ordered standardization of the input codes for electronic navigational systems worldwide.</p><p></p>
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<img alt="" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/making-air-travel-safer-03.width-990_astGI5n.jpg"/>
<figcaption>With small pieces of debris spread over a large swath of swampland, NTSB investigators said the recovery site of ValuJet Flight 592 was the most challenging one they had ever encountered up until that time.
        
        <div class="credit">Courtesy National Transportation Safety Board</div>
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<p></p><h2>ValuJet Airlines Flight 592 | May 11, 1996</h2><p>This tragedy, which caused the deaths of all 110 people aboard, led to significant aviation policy changes, a 24-count criminal indictment against the airline's maintenance contractors, and, ultimately, the downfall of the carrier. The crash occurred in the swampy Florida Everglades shortly after the DC-9 took off from Miami International Airport en route to Atlanta. An uncontrolled fire broke out in the cargo hold and disabled the plane's electrical system. NTSB investigators determined that volatile oxygen-generating canisters incorrectly labeled as empty and illegally stowed by maintenance technicians in the jet's cargo hold exploded, unleashing an inferno. After ValuJet 592, all planes would be retrofitted with smoke detectors and fire-suppression equipment in cargo holds. Furthermore, the FAA enacted stricter rules regarding the transportation of hazardous materials by air and banned chemical oxygen canisters. Finally, it initiated a formal review of its own procedures for overseeing airlines' maintenance contractors.</p>
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<h2>TWA Flight 800 | July 17, 1996</h2><p>Flight 800, a Boeing 747 flying to Paris from New York's JFK International Airport, plunged into the ocean off Long Island, New York, after a catastrophic break-up shortly after take-off. None of the 230 people aboard survived. With the Summer Olympics set to begin in Atlanta in two days, speculation of a terrorist bombing immediately arose. But after one of the most intricate inquiries in aviation history, which included the first full-scale re-creation of a downed aircraft from its debris, NTSB investigators ruled out terrorism. They focused instead on the aircraft's near-empty center fuel tank, where, they determined, an explosion of still unknown origin brought the plane down. The NTSB's recommendations focused on the flammability of the 747's fuel tank, including its potential ignition sources, design, and certification standards, and on the maintenance and aging of the aircraft's other systems, particularly wiring and fittings that could spark or overheat. Within two years of the crash, new fuel-management procedures were required for all 747s.</p><p></p>
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<img alt="Collected Fragments" class="richtext-image full-width" src="https://www.pbs.org/wgbh/nova/media/images/making-air-travel-safer-04.width-990_OIgEjd6.jpg"/>
<figcaption>Thousands of fragments from Swissair Flight 111 were collected as part of the crash inquiry and held in a giant hangar, where investigators pored over them seeking clues to the disaster's cause.
        
        <div class="credit">© AFP/CORBIS</div>
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<p></p><h2>Swissair Flight 111 | September 2, 1998</h2><p>This flight on an MD-11 plummeted into the sea off Nova Scotia, Canada, while traveling from New York to Geneva at night. All 229 people on board were killed. The crash occurred after the pilot radioed that there was smoke in the cockpit and requested an emergency landing. As he dumped the aircraft's fuel, vectored for a runway at Halifax's airport, and reported an escalation of the emergency, Flight 111 disappeared from radar. After a four-and-a-half-year investigation, which revealed evidence of an in-flight fire above the cockpit caused by faulty wiring and fueled by flammable airframe insulation, Canada's Transportation Safety Board published its final recommendations. These included toughening flammability standards for all materials used in airplanes and more stringent testing and certification of electrical wires. The FAA ultimately issued an order requiring the replacement of insulation in 700 commercial jetliners in the U.S., including every MD-11 in service. At least 500 other MD-11s worldwide were also modified. (In Sources below, see an update regarding NOVA's 2004 program "Crash of Flight 111.")</p><h2>Alaska Airlines Flight 261 | January 31, 2000</h2><p>All 88 people aboard perished when this MD-83 aircraft nose-dived with devastating force into the Pacific Ocean off southern California. Flight 261 had left Puerto Vallarta, Mexico, and was en route to San Francisco when it ran into trouble. At 28,000 feet, the crew reported problems with the plane's stabilizer trim (small flaps on the horizontal portion of its tail) and were unable to control the pitch of the aircraft. Moments later, they began an uncontrolled descent. In its investigation, the NTSB found that too little grease on the jet's jackscrew, a tail component that helps move the plane's stabilizer, had promoted excessive wear on its threads. Their report blamed Alaska Airlines for shoddy maintenance standards and the FAA for approval of these standards, which increased the likelihood of inadequate greasing. Changes have since been made to Alaska Airlines' maintenance procedures and the FAA's oversight apparatus, but federal prosecutors eventually opened a criminal probe into the crash.</p><h2>American Airlines Flight 587 | November 12, 2001</h2><p>Just two months after the four airplane disasters of September 11, 2001, an Airbus A-300 taking off from New York's JFK International Airport for Santo Domingo, Dominican Republic, crashed into a neighborhood in Belle Harbor, Queens, immediately raising fears of another terrorist attack. Five people on the ground and all 260 people aboard the plane were killed. The NTSB ruled out terrorism, focusing instead on the plane's vertical tail stabilizer and rudder, which snapped off as the plane fell from the sky. Several months after the accident, the NTSB issued two safety recommendations involving the A-300's vertical stabilizer and rudder, pointing out that some maneuvers can lead to structural failure. As a result of the warnings, Airbus is addressing these issues and American Airlines has implemented regular inspections of the tail sections on all its A-300s.</p>
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<p data-block-key="a5y5f">Horrifying as they are, the worst airline accidents spark the most safety improvements.</p>

Lexi Krock

Articles