Sunday, December 30, 2012

A Fallacy, Naturally

Volcanic eruptions must be good, right?

If I could reverse one trend in the year ahead, it would be the use of the word "natural" in advertising. Our legal system spent too many resources in 2012 wrestling with whether products like Sobe® lifewater® or Dreyer's ice cream could legally claim to be "all natural" (the lifewater suite was dismissed, the Dreyer's suit was allowed to continue).
   Even if we could agree on what is natural, all-natural, unnatural or not-in-the-least-bit-natural, nothing can be ascertained from such information. British philosopher Julian Baggini says "There is no factual reason to suppose that what is natural is good (or at least better) and what is unnatural is bad (or at least worse)."
   The idea that chemicals are artificial and necessarily bad is absurd. Everything including our own bodies are made of the same basic building blocks. Living things, both plant and animal, require the same ~30 elements to live and be healthy. We would be much better served by reading the calorie and fat content of that ice cream instead of trying to figure out if the chocolate is natural.
   Most biologists denounce an appeal to nature (also known as a naturalistic fallacy) because they want to describe the natural world honestly, without extracting morals about how we ought to behave. Canadian psychologist Steven Pinker explains "If birds and beasts engage in adultery, infanticide, cannibalism, it must be OK. The moralistic fallacy is that what is good is found in nature. It lies behind the bad science in nature-documentary voiceovers: lions are mercy-killers of the weak and sick, mice feel no pain when cats eat them, dung beetles recycle dung to benefit the ecosystem and so on. It also lies behind the romantic belief that humans cannot harbor desires to kill, rape, lie, or steal because that would be too depressing or reactionary." I could not agree more.
   Maybe I'm just more sensitive to crass marketing than most—I don't know. It could be because I work in the industry, so bad marketing hits a nerve with me. Or maybe it just bothers me that these sort of tactics work so well—a sign of a generally uneducated public, at least as far as science is concerned. I borrow from the Irish comedian Dara O Briain: "Science knows it doesn't know everything; otherwise, it'd stop. But just because science doesn't know everything doesn't mean you can fill in the gaps with whatever fairy tale most appeals to you." 
   Don't even get me started on what marketers have done with the word "organic".

Sunday, December 23, 2012

Understanding the Big Bang

An artist’s concept illustrating the expansion of
the Universe after the Big Bang.

The term Big Bang was originally coined by the English astronomer Fred Hoyle in an attempt to help listeners to a radio program that he was a guest on understand the difference between it and the popular Steady State theory of which he was a proponent. The Steady State theory had been around since 1920 and proposes that matter in the Universe was being continually created, and had existed pretty much as it does today for all time. 
   In 1931, the Belgian physicist Georges LemaĆ®tre first suggested the evidence for the expansion of the Universe, if projected back in time, meant that all the mass of the Universe was at some point concentrated into a single “Primeval Atom”. Einstein initially refused to accept the concept, telling LemaĆ®tre that “Your math is correct, but your physics is abominable.” It would take Einstein another four years to embrace the theory.
   Simply put, The Big Bang theory states that because space is expanding, the Universe must have been much denser in the past. Einstein’s theory of gravity lets us run time backwards to calculate the density of the Universe billions of years ago. As a result we know that the observable Universe must have expanded from an extremely dense and hot state about 13.7 billion years ago.
   During the Big Bang, matter did not explode into space from a point. The Big Bang was an expansion of space itself that filled all of space with energy right from the beginning. 
Timeline of the Universe.
   Evidence indicates only that the early universe was extremely dense, but not necessarily extremely small. Even though the observable portion of the Universe was once packed into an incredibly small volume, it was not surrounded by empty space—it was surrounded by more matter and energy which is now beyond the observable Universe. This leads to an amazing little-known conclusion: if the whole Universe is infinitely large, then it was always infinitely large, even during the Big Bang.
   Current evidence also tells us that the Universe is either infinitely large, or else is so large that we cannot detect its curvature from what we can observe—similar to how we can not tell that the Earth is round by looking at our back yard.
   The observational evidence for the Big Bang is overwhelming and is known as the Four Pillars of Big Bang Cosmology: Hubble expansion as measured through the redshifts of distant galaxies, the discovery in 1965 of cosmic microwave background radiation, the abundance of hydrogen and helium in proportions predicted to have been produced during the Big Bang, and the formation of galaxies and large-scale structure such as galactic superclusters.
   But the Big Bang is not the whole story—its details are a subject of intense research. The Big Bang theory says nothing about how the universe came into being in the first place—it just assumes that energy, space and time already existed. And because current description of physical laws do not yet apply to such extremes of nature, we may never know what actually happened during the Big Bang. 

Monday, December 17, 2012

Space: The Misunderstood Frontier

According to Einstein’s theory of general relativity,
gravitational attraction between masses results from
their warping of space and time.

This week I am going to deal with some popular misconceptions about space and the Universe in general. Next week I will tackle the Big Bang theory.
   First off, we must realize that when we look out in space we are looking back in time. It takes a long time for the light from distant objects in the Universe to reach us. Light from the Sun takes eight minutes to reach us, and light from nearby stars takes years. Distant galaxies are seen as they looked millions or even billions of years ago. Galaxies extend out far beyond what we can see today, but how far no one knows. Because the Universe has been evolving and expanding over time, most of the light from the distant reaches of the Universe has not yet had time to reach us. 
   As far as we can tell, there is no edge to the Universe. Galaxies extend as far as we can detect in every direction with no sign of diminishing. Even though galaxies extend much further than we can see, we don’t know if the Universe is infinite. So when a galaxy is described as being near the edge of the Universe, what is really meant is that it is near the edge of the observable Universe.
   Until Einstein showed that space has structure, astronomers thought of space as just the emptiness that contains matter. But Einstein showed, through his general theory of relativity, that space is flexible and can be warped. Now when we talk about the expansion of the Universe, we are referring to the stretching of space itself—not just galaxies moving apart through space.
   The notion that space is expanding was predicted by Einstein’s theory of gravitation which describes a simple but universal relationship between matter, space and time. It was a prediction that Einstein initially couldn’t embrace. He modified his theory by adding a term to achieve a static Universe that he called a cosmological constant. Later, after observational evidence by Edwin Hubble indicated that the Universe was indeed expanding, Einstein abandoned his constant calling it his biggest blunder.
   Today, we know that not only is the Universe expanding, but that it is expanding at an ever-accelerating rate. Cosmologists use the term “dark energy” to explain this mysterious energy that Einstein had embraced, then discarded. The best explanation we have today for dark energy is that it is a vacuum energy associated with virtual particles—quantum fluctuations which produce particle pairs that blink into existence and then annihilate in a times pan too short to measure. This happens everywhere, throughout the Universe. But there is a big problem with this theory—vacuum energy is far too weak to account for the acceleration of the expansion of the Universe. One thing is clear—discovering the properties of space remains one of the core problems of modern science.

Sunday, December 9, 2012

Ten Great Moments in Science

This week’s quiz will test your knowledge of science history. As you read these ten great moments in science, try to match them up with the year in which they occurred.
   I’m starting something new this week: a ladder competition. If you submit your name along with your answers I will keep a running tally of the top ten scores over time and update the results weekly. See if you have what it takes to make the top ten!

Here are the years to choose from for the ten items below. Each year is only used once.: 1543, 1665, 1687, 1775, 1859, 1905, 1909, 1919, 1923 and 1928.

1) Newton publishes Principia, describing the three fundamental laws of motion forming the basics of classical mechanics. ______

2) Hans Geiger and Ernest Marsden, under the direction of Ernest Rutherford, perform the gold foil experiment which probes the structure of the atom demonstrating the existence of the atomic nucleus. ______

Charles Darwin
3) Darwin’s On the Origin of Species is published and becomes the foundation for evolutionary biology. ______

4) Joseph Priestley discovers oxygen. ______

5) Albert Einstein’s Miracle Year, where he publishes four articles that contribute to the foundation of modern physics, covering the photoelectric effect, Brownian motion, special relativity and mass/energy equivalence. ______

Nicolaus Copernicus
6) Nicolaus Copernicus describes a heliocentric solar system with the Earth and other planets revolving around the Sun, challenging the common perception at the time that the Earth was the center of the universe—as had been the assumption since the time of the Greeks. ______

7) Alexander Fleming discovers penicillin, the world’s first antibiotic. ______

8) Arthur Eddington observes the bending of light during a total solar eclipse, confirming Einstein’s theory of general relativity. ______

9) Robert Hooke coins the term “cell” to describe the building blocks of life that he saw and described in his book Micrographia. ______

10) Edwin Hubble discovers that Andromeda is a galaxy, proving that the Milky Way is only one of hundreds of billions of galaxies in the visible universe. ______

Saturday, December 1, 2012

Did Einstein Really Say That?

It is very popular, nowadays, to strengthen an argument by quoting Einstein. The problem is that many of the quotes attributed to Einstein were never actually his. Some were him repeating a quote of another individual, but many others seem to be completely made up. Einstein has become the source to a treasure trove of phony quotes, largely because the internet has enabled us to share so much without sourcing anything.
   Einstein did not humiliate an atheist professor as an undergraduate, but Google returns over 61,000 hits on the subject. Nor did he trade places with his chauffeur and let the driver give his lecture instead. Recently, Einstein has been resurrected to say that if all the bees disappeared mankind would be extinct in four years. A classic case of a quote being invented and attributed to someone famous to give it extra credence. Einstein has been used by both sides of the debate on religion.
   So, how well do YOU know what Einstein said? Take our quiz and find out—you might be surprised.

Saturday, November 17, 2012

The Last Arctic Penguin

Penguins today are not found north of the Equator, except in zoos and on Christmas cards, but this was not always the case. What follows is a sad tale of how the penguin of the north met its demise. 
   Off the coast of England, secluded by blankets of fog and gray rain clouds, is Lundy, which translates to the old Norse words for “puffin island”. This enormous block of granite rises over a hundred meters above the treacherous seas that surround it. Its towering, rocky cliffs and ledges providing breeding grounds for thousands of seabirds. It was here in 1835 that an islander saw a pair birds, the likes of which he had never seen before. He called them the “king and queen murres...because they were so big and stood up so bold-like”.
   Only one bird fits such a description. By the time of this encounter, the species in question had become so rare that to locals they were little more than legend. They spoke of a murre so large it was unable to fly, with a beak big enough to make that of its cousin, the Razorbill, seem small in comparison.
The Great Auk, although not directly related
to the King Penguin, filled a similar ecologic
niche in the north that the King Penguin fills
in the south.
   This original “penguin” was in fact the now-extinct Great Auk (Pinguinus impennis), once found in vast numbers around northern shores of the Atlantic. Although no relation to true penguins, they were similar in appearance, filling much the same ecological niche as the King Penguin that lives on the islands around Antarctica. In fact the word “penguin” was initially a synonym for Great Auk, and is thought to have come from the Welsh pen gwyn which means “white head”. As Europeans travelled to southern seas, the word was used to describe the birds they found there.
   As the Great Auk passed into legend among the people of the North, it was quickly acquiring a prominent reputation among collectors. Its last hideouts were sought out by seamen looking for specimens to sell to wealthy collectors and museums for incredibly high sums.
   Some 78 skins and 75 eggs have been recorded and throughout the nineteenth century examples were regularly offered for sale, many of them at Stevens Auction Rooms in London, a venue celebrated for the natural history items they sold. So close was the connection of this firm with the dispersal of remains of the Great Auk, that its address was simply, “Auks, London”. In early years, Great Auks and their eggs fetched just a few pounds each but by 1900 a choice egg sold for £330. By 1971, a stuffed bird sold in London to an Icelandic museum for a record £9,000.
Great Auk (Pinguinis impennis)
specimen and replica egg, Glasgow.
   The eggs of the Great Auk, for which there was such fierce competition, were dirty yellow-white in color, particularly around the fat end, with an irregular pattern of pale grey or brown. A single, large egg was laid—about as large as an Emu egg, and pyriform shaped, so that when nudged they move in a tight circle instead of rolling away and being dashed to bits on the rocks. This feature is of great importance to a bird that makes no nest. 
   On the rocky platforms that provided the Auks with their home, territory would be defended by a few low croaks. The beak could be used to administer an unpleasant bite but, apart from this, Auks were more or less defenceless.
   At breeding colonies, their great size set them apart from the other murres but they could also be immediately distinguished from the Guillemot and the Razorbill by their more upright stance. Most eggs were found in June and hatched by July. Their diet was made up of fish, crustaceans and other marine invertebrates which the Auk could pursue through the water with tremendous speed and agility.
   At one time the Great Auk was widely distributed across the North Atlantic, from the Gulf of St. Lawrence in the west to Norway in the east and as far south as the Channel Islands. The Little Ice Age pushed the Auks south as these birds could not thrive under arctic conditions. With the advance of the great ice sheets during this time, more of their breeding islands became exposed to polar bears.
   Despite their wide distribution, Great Auks preferred to breed in colonies at just a few select locations, leaving many seemingly suitable sites unoccupied. Rookeries were known to exist at the Gulf of St. Lawrence, the Newfoundland coast, near Iceland, and at St Kilda.
   The Great Auk was an excellent swimmer, using its wings to propel itself underwater. On land it was clumsy and slow, waddling as it dragged itself across rocky shores. Their large size, combined with a pathetic inability to fly or evade capture, made the Great Auk an easy target for hunters. To those who eked out a meager living among the bleak isles of the north, or sailors and fishermen anxious to replenish stocks before venturing into the icy waters of the Arctic, such a bird was irresistible. Vast numbers were slaughtered for their feathers which were used to make pillows. On Funk Island, the unfortunate creatures were herded into pens, clubbed to death and tossed into vats of boiling water to loosen their feathers. The fires beneath these cauldrons were fuelled by the fat and oil from auks that had already met a similar fate.
   By 1800, the Great Auk was all but gone. The few recorded encounters with the species after this time make up a sordid list of human cruelty and ignorance. One bird was captured on St Kilda. Two men and two boys spotted it from a boat, sitting upon a low ledge. The men landed at either end of the shelf and began a steady approach while the boys rowed close to the rock, just below the spot where the bird was resting. As the men drew nearer, the Auk, by now becoming increasingly alarmed, made a desperate bid for the safety of the water but instead jumped straight into the arms of one of the waiting boys. This bird was kept alive and sent to Edinburgh, but managed to escape during one of its leashed swims, never to be seen again.
   Many years later, an elder resident of St Kilda claimed to have caught a Great Auk with the help of two accomplices. The bird was found sleeping and was captured and taken to the islander’s hut. There they kept it in captivity for three days, until a big storm arose. Thinking that the bird had caused the storm and was really a witch, they clubbed it to death.
Eldey island, the last home of the Great Auk.
   The Great Auks’ last colony was on Geirfuglasker, an islet off the coast of Iceland, but in 1830, it was sunk by volcanic activity. Nearly 50 of the surviving birds continued to breed on the nearby Eldey island and it was here that the species was hunted for the last time. The colony had been ravaged by museum collectors for over a decade, when on the morning of July 3, 1844, a party of three sailors landed on the island. Among a group of Guillemots, they spotted a pair of Great Auks and immediately attacked. The frightened creatures frantically tried to escape, but were overtaken. One was trapped between rocks and the other captured just a few steps from safety. Both were strangled to death. The female had been sitting on an egg which was crushed during the scuffle. Their skins were sold to a collector in Reykjavik. And while no doubt other individuals lingered here and there, soon after, somewhere in the cold and lonely waters of the North Atlantic, the last arctic penguin died.

Monday, November 12, 2012

The Water Quiz

Water is quite arguably the most important substance on Earth. Without it, life could not exist. Its high polarity makes it a universal solvent, able to dissolve both organic and inorganic compounds. And because it exists as a liquid at room temperature, it can transport those compounds through the body. It's high surface tension and adhesive/cohesive properties allows capillary action. In plants, water flows against gravity from the roots through the plant stem to provide nutrients to the rest of the plant. 
   How much do you know about this incredible substance? Take this week's quiz and find out.

Saturday, November 3, 2012

The Black Swallower

The Black Swallower is a deep sea fish notable for its ability to swallow fish much larger than itself. It lives in tropical and subtropical waters, in the pelagic zone at a depth of 700 to 2,745 meters below sea level. This unusual fish is small—none longer than 25 cm in length have been found. As their name suggests, they are black in color. They have an unusual jaw—the lower jaw extends past the upper and their single row of teeth interlock when they close their mouth to create an eating trap. 
   When the Black Swallower preys, it eats its victim whole. It has a distensible stomach that can hold prey twice its own length and ten times its own body mass. Its hinged jaw has the capability of surrounding prey much larger than the Black Swallower’s head. As the Swallower eats, it starts at the tail and slowly walks its jaws up the fish’s body until fully consumed. But that it eats its prey like a some sort of aquatic python is a matter of supposition as nobody has ever observed the Black Swallower alive.
   Scientists don’t get to see these creatures in action, only as the result of a deathly case of indigestion. Usually the Swallower will bite off more than it can chew and swallow a fish so big that it can’t digest the whole thing. After a few days its meal starts to decompose and release gasses that get trapped inside the creature. Like a balloon, the extra buoyancy brings the fish to the surface where it can be collected and observed. 
In 2007, this Black Swallower was found having bitten off
more than it could chew—an 89-cm long snake mackerel.
   In 2007, a local Cayman Islands fisherman found a Black Swallower that had risen to the surface. In its stomach was a fish called a snake mackerel that was more than four times its own body length. This particular Swallower, at 19 cm in length, had eaten a fish that was over 86 cm long! Could this be where the saying “Never bit off more than you can chew.” came from?!

Monday, October 29, 2012

Dead Sea Diving

The Dead Sea has such a high saline content
that pillars of salt form near its banks.

Lying on the border of Israel and Jordan, the Dead Sea is a one of the best-known examples of a hypersaline lake. With a salinity of 33.7 percent, it is more than ten times saltier that the ocean. And at 377 meters deep, it’s also the world’s deepest hypersaline lake. 
   The Jordan River used to feed fresh water into the Dead Sea, but in the 1950s it was diverted to supply drinking water to Israel and Jordan instead. This lowered the lake’s water level, and it continues to drop more each year. Water levels have fallen by more than 25 meters over the last 40 years. Since the basin has no outlet, water only escapes by evaporation, leaving behind salt and other minerals. Over time, this made the Dead Sea much saltier than ocean water.
   Fish can’t survive in the Dead Sea, but it’s not totally lifeless. Extremophiles—organisms adapted to live in extreme conditions such as high temperature or salinity—do live in the Dead Sea. Salt-loving microbes known as halophiles can survive and thrive in the lake.
   In 2010, researchers from Ben-Gurion University found several giant craters at depths of 30 meters spewing fresh water and brimming with bacteria at the bottom of the otherwise barren lake. The craters were covered with thick layers of a new microbial species that live near fresh water plumes that shoot from underwater springs.
   Reaching the springs is a bit of a challenge. Divers carry about 40 kg of weight to lower their buoyancy enough to sink, since the salty water is so dense it makes you float. They also must wear full face masks to protect their eyes and mouths. Getting Dead Sea water in your eyes could cause blindness and swallowing it would cause choking and possibly suffocation.
   The bacteria they found were similar to what you’d find living in a regular saltwater ocean. These bacteria use both sunlight and sulfides to survive. Not only have the organisms evolved in such a harsh environment, the bacteria can cope with sudden changes in salinity as fresh water and saltwater currents swirl around the springs.
   Normally, highly salt-adapted bacteria die when placed in fresh water, and fresh water bacteria die when they come in contact with salt water. Researchers claim that being able to live in both environments is something very unexpected and deserves further study. 

Saturday, October 20, 2012

The Evolution of Sight

The compound eye of the Arctic krill is highly evolved
for such a small creature.

Our vision is based upon a very small sliver of the electromagnetic (EM) spectrum. Humans can sense EM radiation between the wave lengths of 380 nm and 750 nm, ranging from violet through red. We cannot see, however, all the electromagnetic chatter that is happening around us outside the visible range. We’re bathed in an ocean of electromagnetic waves all day, every day. There is nothing qualitatively different about the visible portion of the spectrum compared to radio waves or ultraviolet waves, for example; it’s just that we can sense some waves (which we call light), yet have no awareness outside this narrow range.
   There’s a very good reason for this—it’s not just a coincidence. It’s because of the way light attenuates in water. Attenuation is the physical property that describes the gradual decrease in intensity of electromagnetic radiation as it travels through a medium—in this case sea water. When the Sun’s rays reaches the surface of the ocean, visible light is absorbed at the longest wavelengths, red and orange, first. Blue and violet wavelengths reach deeper into the water column, which is why deep-ocean water appears blue.
The attenuation (decibels/meter) of EM radiation in water as a function of wavelength (nm). EM attenuation in water drops six orders of magnitude just around the visual range.
   Now expand this concept to the entire spectrum of EM radiation. Species began to evolve eyes during the Cambrian explosion (about 540 million years ago), while life was still confined to the sea. Eyes developed sensitivity to the 380-750 nm range because that band of EM radiation travels through water with an attenuation 1,000 orders of magnitude lower than that of adjacent wavelengths. Being able to see in deeper water provided an evolutionary advantage, so the earliest animals developed sensitivity in the portion of the spectrum that reached the greatest depth. During this time the eye developed rapidly. After creatures began to move onto land, there was no evolutionary incentive to see a larger portion of the spectrum because every other organism also saw in this range.
A Trilobite fossil with the eye structure outlined in red.
   Sight gave predators the ability to find prey, triggering an evolutionary arms race where animals either evolved or died. Trilobites possessed highly-advanced compound eyes that gave them a competitive advantage in both finding food and avoiding predators. It’s no surprise that trilobites thrived during the Cambrian explosion to become one of the most diverse and successful classes of all the early animals, roaming the oceans of the world for the next 270 million years. Continual adaptation during the Cambrian explosion was needed in order to maintain relative fitness amongst all the other species that were evolving at the same time. This is known as the Red Queen Effect, a term taken from Lewis Carroll’s Through the Looking-Glass where Alice and the Red Queen are running yet not getting anywhere: 
   “Well, in our country,” said Alice, still panting a little, “you’d generally get to somewhere else—if you run very fast for a long time, as we’ve been doing.”
   “A slow sort of country!” said the Queen. “Now, here, you see, it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!”

Monday, October 15, 2012

The Antarctic Paradox

A phytoplankton bloom off the
coast of Argentina.

Recently I wrote about how the population of Antarctic krill has dropped by 80% over the last 40 years. I have to admit, I was feeling a bit depressed after writing that column. It seems that the natural world is forever being drop-kicked at the expense of progress. But are the two competing worlds forever destined to be in conflict? Maybe not.
   Let’s look a little closer at the problem of declining krill numbers. It’s paradoxical that there are vast areas of the Southern Ocean that contain plenty of nutrients to support phytoplankton growth, the primary food source for krill, yet we don’t see the growth that would normally be expected. These low-plankton regions near Antarctica are called HNLC areas because the have High Nutrient yet Low Chlorophyll.
   The main reason for this is a lack if iron in the water. Iron is an element that is required in trace amounts for photosynthesis to take place, but it is insoluble in sea water, making it a limiting nutrient for plankton growth.
   Over the last 20 years, there has been considerable research into the problem and it has been shown that phytoplankton growth can be stimulated by adding iron. Usually such iron fertilization occurs naturally by ocean current upwellings, wind-born dust being deposited over the ocean’s surface or iron-rich minerals being carried to the ocean by glaciers or icebergs. 
   And there is another potential benefit beyond boosting the bottom of the food chain. When Mount Pinatubo erupted in 1991, it deposited about 40,000 tons of iron-rich dust into the world’s oceans. What happened as a result was remarkable: over the next few years, phytoplankton blooms increased substantially, causing planetary carbon dioxide levels to drop and oxygen levels to increase. It was estimated that over a billion tons of CO2 was removed from the atmosphere.
   There are now plans underway to do this on a large-scale, commercial basis. However, there is considerable uncertainty and disagreement as to whether it will do more harm than good on a large scale. Some scientists remain skeptical about whether the process would remove carbon dioxide for the long term and what the ecological impact will be. Further experimentation is needed and one thing is for certain: future policies and carbon-offset markets will emerge, and possibly without a sound scientific basis. Iron fertilization should be considered along with any other geoengineering solution. And if it feeds a few more whales in the process, all the better.

Sunday, October 7, 2012

A Strange Sight Over Moscow

On October 7th, 2009, a strange-looking formation was seen in the sky over Moscow. When it appeared, scores of supernatural enthusiasts speculated that it had been created be an alien spacecraft. Turns out, it was actually a hole-punch cloud. Because the center of the formation appears to be a falling streak of clouds, nepholologists call it a fallstreak hole. 
   A fallstreak hole is a large circular gap that can appear in cumulus clouds, usually at an elevation of six kilometers or more above the Earth. Such holes form when a cloud is made of both ice crystals and super-cooled water droplets that exist together in a delicate balance. When such a balance occurs, it only takes a slight disruption, such as a passing jet, to set off a chain reaction that transforms the super-cooled water droplets into ice which clings to existing ice particles. The quick build-up of ice falls from the cloud and dissipates the water, creating a void.
   Hole-punch clouds are rare, but when they do form, they’re large enough to be seen for many kilometers in every direction. Because they are so rare and have an unusual appearance, fallstreak holes are often mistaken for UFOs.
   Upon further investigation of the Moscow hole-punch cloud incident, it seems to have been inadvertently caused by the Russian Air Force—at the request of Yury Luzhkov, Moscow’s mayor—to test its cloud-seeding program. The idea was to fly over the approaching clouds and spray silver iodide into them. Moisture would quickly condense around the fine particles, creating snow much sooner than it would normally. 
   In theory, if the clouds shed enough precipitation before reaching the city, Moscow could avoid the usual heavy winter snowfalls for which they are so well known. Luzhkov said such efforts could save the city $4 million in snow-removal costs each year, and improve their quality of life during winter.
   But there was a problem: Mother Nature refused to cooperate. The pilots needed two weeks advance notice for maximum effectiveness, yet meteorologists had a hard enough time predicting snowfall two days in advance. So while Luzhkov blamed the hapless weathermen and promised to find a solution, Muscovites did not hold their breath. 

Monday, October 1, 2012

Bengal Tigers of the Sundarbans

The Sundarbans is a United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage Site covering parts of Bangladesh and India. The region is densely covered by mangroves, and is the largest mangrove forest in the world. It is also one of the largest reserves for the Bengal tiger.
   The Sundarban forest lies in the expansive Bay of Bengal delta. Inland from the mangrove forest lies the seasonally flooded Sundarbans freshwater swamp. The Sundarbans is estimated to cover about 4,100 square kilometers and serves as a protective barrier against cyclone flooding. 
   A 2007 UNESCO report states that a likely 45-cm rise in sea level by the end of this century, along with other human-derived stresses, could lead to the destruction of 75% of the Sundarbans mangroves. 
A satellite image of the Sundarbans.
   The Sundarbans is intersected by a complex network of tidal waterways, mudflats and small islands of mangrove forests. Almost every part of the forest is accessible by boat. The fertile soil of the delta has been used for agriculture for centuries, with the forested regions dwindling to about one third the size that it originally measured some 200 years ago. What remains, along with the Sundarbans mangroves, is an important habitat for the endangered Bengal tiger. 
   Over the past century, the tiger population has fallen dramatically, and continues to decrease. Loss of habitat and poaching are the two most-serious threats to their survival.
   In 2006, the Indian government granted some of their most impoverished communities the right to own property in the forests, which brings them in conflict with the Bengal tiger. Tiger attacks in the Sundarbans kill from 50 to 250 people each year. Although precautions that were enacted in 2004 temporarily stalled the attacks, recently attacks have been on the rise. In 2007, Cyclone Sidr devastated the Bangladesh side of the swamp, depriving the tigers of their usual food sources and pushing them towards the more populated Indian side of the Sundarbans.
   Villagers tried wearing face masks on the back of their heads to confuse the tigers, which prefer to attack from behind. This worked for a while until the tigers figured it out, after which the attacks continued. Government workers wear strong padding on the back of the necks, similar to those worn by U.S. football players, to prevent the tigers from biting their spine. This is their favorite method of attack.
   Villagers in the area occasionally release livestock into the forest in order to provide an alternative food source for the tigers and discourage them from coming into the villages. The government subsidizes the project to encourage village participation.

If you enjoyed this article you might also want to read my article on the Siberian Tiger Project.

Monday, September 24, 2012

When the Lights Go Out

One of my readers posed the question: When I turn off the light in my bedroom at night, where does all the light go? Before we answer this, we need to make a few assumptions. Let’s assume that the bedroom is a perfect container: It has no windows for light to escape from and no cracks around the door so light can’t escape there either. Also, let’s say the walls are perfectly solid, and consist of a regular structure of atoms. Imagine a grid of hard spheres laying next to  each other. This is the surface of the walls. 
   First, we need to realize that light is a form of energy. While the light switch is on, it closes an electric circuit and electrons flow through the light bulb. The light bulb converts the energy from the electric current to light energy in the form of photons. Photons are tiny packet of electromagnetic energy and momentum. When you turn the light off, the circuit is broken, the energy stops flowing, and the light goes away. But where does it go?
   The photons travel across the room at the speed of light. When a photon hits the wall, its energy and momentum is either absorbed by the atoms in the wall, or are reflected to another wall where it again may get absorbed or reflected. One of the fundamental concepts of physics tells us that both energy and momentum are conserved, which means that an atom will get a small kick from absorbing a photon. It will move, and kick against its neighbor, etc. If enough photons get absorbed, this will result in the wall warming up slightly. So the light gets converted into thermal energy in the wall. This is what is meant by having a temperature. 
   If the wall were at absolute zero, these atoms do not move and are simply at rest, each one just touching the next. By saying that the wall has a temperature, we are really saying that it contains thermal energy. This thermal energy is the random vibration of the atoms around their equilibrium point. Such a vibration can travel through the grid of atoms in the form of a wave. One atom pushes the next, which pushes the next, etc. 
   When you turn off the light switch, the process just stops—the bulb stops generating photons, and the last set of photons hit walls until they’re all absorbed, all within a fraction of a second.

Monday, September 17, 2012

The Keystone Species of the Southern Ocean

A swarm of krill in the Southern Ocean

Worldwide there are about 85 species of krill, the largest of which is the Antarctic krill (Euphausia superba) which averages about five centimeters in length. Antarctic krill live in dense concentrations in the cold Southern Ocean. At any given time there are four or five billion individuals, and when they congregate for spawning they create a pink swarm so large that it can be seen from space.  
   Krill are crustaceans like crabs, shrimp and lobsters. But unlike their cousins that are bottom-feeders, krill are pelagic—they make their living in the open ocean. And unlike the plankton they feed on, krill are nektonic—they are able to swim independent of the ocean currents. 
The anatomy of the Arctic krill
   Antarctic krill feed on algae and phytoplankton that are suspended in the water column. They are preyed upon by nearly every Antarctic predator that exists. And if a predator doesn't eat krill, it feeds on the ones that do. A penguin's diet consists of nearly 100 percent krill. Blue whales rely on krill for almost all of their dietary requirement. During the summer months, an adult blue whale eats up to 40 million krill in a single day to fulfill its 1.5 million kilocalorie nutritional needs. Antarctic krill is the keystone species in the Southern Ocean, and without it, the ecosystem would collapse.
   Antarctic krill use intensive searching and rapid feeding techniques to take advantage of high plankton concentrations. Krill form dense schools that move horizontally in the water column when feeding. Krill spend their days avoiding predators in the cold depths of the Southern Ocean. At night, they drift up toward the surface to search for phytoplankton.
   Recent studies show Antarctic krill stocks have dropped by as much as 80 percent since the 1970s. Scientists attribute this decline in part to ice cover loss caused by global warming. This ice loss removes ice algae from the Southern Ocean which is a primary source of food for krill. NASA satellite data reveals that there has been continuous ice loss from Antarctica since 2002—more than 100 cubic kilometers of ice per year.

Monday, September 10, 2012

The Skies Near Mount Ranier

Located southeast of Seattle, Mount Rainier is the tallest volcano in the Cascade Range and the most topographically prominent mountain in the contiguous United States. Its summit is at an elevation of 4,392 meters and it has a topographic prominence of 4,027 meters. Because of this, many people from the Pacific Northwest are treated to the spectacular beauty of this snow-capped peak which dominates the landscape. But if you are really lucky, your view of Mount Ranier could be enhanced in some very unusual ways. 

A cloud shadow being cast from Mount Rainier. Photo by Nick Lippert.
   One way is by an amazing cloud shadow that only occurs with several factors happening concurrently. At the approach of winter, when the Sun rises farther to the south, it is possible for the first rays of light at sunrise to pass through a dip in the Cascade Range and catch the peak of Mount Ranier. If that sunrise is also accompanied by a cloud layer above the mountain, it will project a shadow onto the bottom of the cloud layer creating a spectacular cloud shadow. This could never happen in the Rockies because even though there are several peaks taller than Mount Ranier, none of them have the topographic prominence that is needed. And as the sun rises its light will scatter too much to cast a shadow behind it.

   Another strange yet beautiful cloud phenomenon that you can see near Mount Ranier is lenticular clouds. These are lens-shaped clouds that form at high altitude. Because of their smooth, saucer-like shape, lenticular clouds have been mistaken for UFOs. Lenticular clouds are formed when moist air travels vertically over the mountain and creates a standing wave pattern on the downwind side. Moisture condenses at the crest of the wave and evaporates at the wave trough, creating the characteristics lens shape. Even though the wind continues to move down the mountain, the lenticular cloud will remain stationary. Lenticular clouds can appear singly, or in clusters or stacks. Pilots will avoid lenticular clouds because of the dangerous wind shears that accompany them, but thrill-seeking hang gliders will use them to ride the wave for several kilometers.

A stacked lenticular cloud formation near Mount Ranier.
   At some point in the future Mount Ranier will give us the most-spectacular—yet terrifying—show of all: when it erupts. Even though Mount Ranier is quiet now and has been since the 1890s, geologists consider this stratovolcano to be episodically active, which means that it WILL erupt again at some point in the future. It’s for this reason, and the fact that Mount Ranier is located near a highly-populated area, that it was included as one of 16 “Decade Volcanoes” worthy of study in an attempt to reduce the severity of a future natural disasters. These Decade Volcanoes were studied as part of the United Nations International Decade for Natural Disaster Reduction during the 1990s.

Sunday, September 2, 2012

Brocken Specter

Brocken specter as seen from 
the Golden Gate Bridge.

I love travelling through the mountains. The way the light plays off the mist in beautiful and sometimes eerie ways amazes me. If you're lucky enough to be at the right place at the right time, you might experience a rare and seemingly supernatural optical phenomenon called Brocken specter, named after the highest peak in the Harz mountains in Germany. 
   German Folklore dating back to the 17th century says that on the night of April 30 each year, exactly six months after Halloween, witches and sorcerers gather on the Brocken and revel with their gods as they await the arrival of spring. Among mountain climbers there is a superstition that a person who sees a Brocken specter will someday die on the mountain; local climbers have been so startled by the sudden appearance of a Brocken specter that they fall to their death, not realizing they are seeing their own harmless shadow.
Brocken specter from the 
Tanzawa Mountains in Japan.
   The Brocken specter appears when the setting sun casts a shadow from directly behind a climber at a higher altitude onto a cloud or mist at a lower altitude. When the shadow is cast upon a mist the sunlight surrounding it enters the suspended water droplets in the air and reflect back to the observer via diffraction, creating a rainbow-colored halo around the shadow's head. This halo is called solar glory. 
   The Brocken specter may appear to be huge because the fog hampers your depth perception. Only one's own shadow, seen in a mist, can converge with the antisolar point and combine with the solar glory to create the Brocken specter. Therefore, if you are travelling in a group you can only see your own Brocken specter.
Brocken specter from the Pamir Mountains of Tajikistan.

Wednesday, August 15, 2012

The Neanderthal Genome Project

The majority of the DNA used for the Neanderthal
Genome Project was obtained from the bone fragments
of three females who were excavated from the Vindija
Cave in Croatia. Image: Max Plank Institute for
Evolutionary Anthropology/Frank Vinken.

Found in Europe and parts of Asia, Neanderthal lived from about 400,000 years ago until 30,000 years ago. Neanderthals were comparable in size to Homo sapien, but more robust. They also had similar brain sizes, but their skulls were shaped differently. Researchers have long wondered why Neanderthal went extinct. Some think the lack of genetic diversity made it too hard to persevere through plagues while others think that their smaller, less sophisticated social groups played a part in their demise. We do know that their stronger build would have required more food which would have been a disadvantage during hard times.
   In 2010, scientists from the Max Plank Institute for Evolutionary Anthropology in Germany reported that they had completed a first draft of the Neanderthal genome. This research was based on analysis of four billion DNA base pairs. Through DNA analysis, we have learned insights that had been previously unknown through only fossil evidence. Their study suggests Neanderthals had an effective population smaller than that of modern humans, and lived in small, isolated groups. And although we share about 99.7% of the same DNA, only 1-4% of modern non-African humans have inherited DNA from Neanderthals, and Africans have no common lineage. Most likely, the interbreeding occurred early in the migration of humans out of Africa.

   DNA analysis has also proven fruitful in a recent discovery in a cave in Northern Spain. Researchers there found the butchered remains of an extended Neanderthal family that were killed and eaten by other Neanderthals. The bones were cracked open by stone tools for marrow, suggesting that they were cannibalized before the cave collapsed and buried their remains. Researchers found that the group was genetically very similar, confirming that Neanderthals had less genetic diversity than modern humans. They also discovered through DNA analysis that they lived in small groups of males that were closely related, and that the females came from other tribes, a social system called patrilocality. Clearly, our understanding of human evolution is benefitting greatly from DNA analysis.

Monday, August 6, 2012

NASA Takes Gold in the 567 Billion Meter Dash!

The first image taken by the NASA Curiosity rover after
the dust covers were removed from the cameras.

I watched in amazement last night as NASA pulled off a perfect landing to put Curiosity—the most complex rover ever built—on the Martian surface. Congratulations to all the hard-working men and women at NASA/JPL for not creating a 2.5 billion dollar crater instead! If they were terrified during those seven minutes from when Curiosity entered the Martian atmosphere travelling 20,000 kph until touchdown, I sure could not tell. Nothing but professionalism and ear to ear grins and high fives once it had landed. 
   Curiosity weighs in at 900 kg and is three meters long, larger than some small cars. It is equipped with 80 kg of instrumentation, including a variety of cameras and a laser that is powerful enough to vaporize rock. These are the most-advanced instruments ever used on the Martian surface. Curiosity will be able to determine mineral and soil composition, atmospheric processes, detect chemical biosignatures and characterize the surface radiation on Mars.
   The Mars Science Laboratory’s goals for this mission are to search Mars for signs of life, past or present, study the climate and geology of Mars, and plan for a future manned mission to Mars. The mission is scheduled to last for about two years, but if conditions are favorable, the rover could be in operation for much longer.
   In the weeks and months to come I will be writing more about this incredible mission and its discoveries. In the meantime, to celebrate NASA/JPL’s successfully landing, this week’s quiz is about Mars. See how much you know about the Red Planet.

Monday, July 30, 2012

Two Trees from Socotra

Socotra, part of the Republic of Yemen, is a small archipelago of four islands in the Arabian Sea off the Horn of Africa. Socotra’s isolation from the mainland combined with a tropical desert to semi-desert climate has lead to unique speciation, with more than a third of its plant life being found nowhere else on Earth. The islands contains a wide range of habitats: beaches, mountain ranges, plains and caves. Because of Socotra’s broad diversity it has been described as the strangest-looking place on Earth. 

The dragon blood tree (above) and the cucumber tree (below).

   One of the most impressive of Socotra’s plants is the dragon blood tree (Dracaena cinnabari), which looks very odd with an umbrella shape. Its red sap was thought to be the dragon’s blood of the ancients, sought after as a medicine and a dye since antiquity and highly prized by European Renaissance painters. It was also used as a varnish by 18th century Italian violin makers. 
   The unusual shape of the dragon blood tree is an adaptation for survival in the dry rocky soil where it is found. The large, packed crown furnishes shade and reduces evaporation which helps seedlings survive beneath the adult tree.
   Perhaps the strangest of all the trees on Socotra is the cucumber tree (Dendrosicyos socotranus), which looks like a giant cucumber with its bulbous trunk and tiny crown. It lives on the dry parts of the islands up to about 500 meters in elevation. It is the only tree in its plant family which includes melons, gourds, squashes, and yes, cucumbers.
   Cucumber tree seedlings are eaten by goats that graze on the islands. Mature trees are often cut down and made into pulp which is fed to livestock. The leaves of the cucumber tree are used by the local population to treat a variety of ailments.
   Socotra’s ecosystem is one of the most endangered in the world and it is listed as a World Heritage Site by the United Nations Educational, Scientific and Cultural Organization (UNESCO). Both the dragon blood tree and the cucumber tree are considered vulnerable species by the International Union for Conservation of Nature (IUCN). 

Sunday, July 15, 2012

Fly Geyser

Fly Geyser is a small, 1.5 m high geothermal geyser that is located near the edge of Fly Reservoir, Nevada. The Geyser was accidentally created in 1916 during the drilling of a well when a shaft was drilled in hopes of striking water to turn part of the surrounding desert area into farmland. The well functioned normally for several decades, but then in the 1960s geothermally heated water found a weak spot in the wall and began escaping to the surface, turning the area into a desert wetland. Dissolved minerals started rising and piling up, creating the mount on which the geyser now sits. 

Today, water is constantly squirting out reaching 1.5 m in the air. The geyser contains several terraces discharging water into 30 to 40 pools over an area of 74 acres. The geyser is made up of a series of different minerals, which gives it its beautiful colors. Recently, yet another new geyser has formed. For unknown reasons, the original geyser has gone dormant. One hypothesis explaining this is that later geysers robbed the original of its water supply.

Fly Geyser is a secret tourist attraction located about 200 km north of Reno, Nevada. The Geyser is located in Hualapai Flat, about 0.5 km from State Route 34. It is large enough to be seen from the road. Fly Geyser is located on the privately-owned Fly Ranch and is accessible only by a small dirt road. 

No quiz this week due to summer vacation!