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The Atacama Desert of Chile is the driest place on Earth. The desert is bounded in the west by the Chilean Coastal Range, which blocks moisture from the Pacific. On the east of the Atacama run the mighty Andes Mountains which catch almost all the rainfall from the Amazon Basin. Thus trapped between ranges, the desert receives 4 inches of rain every thousand years. Because of the dryness, people are very sparse in the Atacama: they are found only at rare oases or as desiccated (but well preserved) mummies lying in pits.
The high altitude, dryness, and lack of nearby cities (with their lights and radio waves) make the Atacama a paradise for astronomers. On a mountaintop 8000 feet up on the Atacama side of the Andes, engineers and scientists are working to put together one of the wonders of this age.
The Giant Magellan Telescope (hereafter the “GMT”) will be a miracle of engineering. When it is completed in 2019 it will be larger than any telescope on Earth. The scope is so giant that it will be mounted in a huge open, moving building (rather than the gun-turret-like buildings observatories are traditionally housed in). No organization on Earth is capable of making a mirror large enough for the necessary purposes, so seven immense 8.4 meter mirrors are being used together to create a single optical surface with a collecting area of 24.5 meters (80 feet in diameter). The mirrors are the pinnacle of optics: if they were scaled up to the size of the continental United States, the difference between the highest and the lowest point would only be an inch.
The scope will be much more powerful than the Hubble telescope and take much clearer pictures despite being within the atmosphere of Earth. In the past decade, telescope makers have used cutting edge engineering to compensate for atmospheric distortions. To do so they fire multiple lasers grouped around the primary mirrors high into the atmosphere. These beams of light excite sodium atoms in the sky which fluoresce—creating tiny “stars” of known wavelength, which serve as points of reference for the adaptive optics. The official website of the GMT further explains the mechanism used to counteract atmospheric turbulence once these benchmarks are obtained:
The telescope’s secondary mirrors are actually flexible. Under each secondary mirror surface, there are hundreds of actuators that will constantly adjust the mirrors to counteract atmospheric turbulence. These actuators, controlled by advanced computers, will transform twinkling stars into clear steady points of light. It is in this way that the GMT will offer images that are 10 times sharper than the Hubble Space Telescope.
The telescope is designed to solve some of the fundamental mysteries about the universe. Scientists hope it will help them find out about the nature of dark matter and dark energy (which are thought to make up most of the mass of the universe). Astronomers also hope to find out how the first galaxies formed and (perhaps) to ascertain the ultimate fate of the universe. Most excitingly of all, the telescope should be large enough to peek at some of the exoplanets we are discovering by the thousands. If life exists anywhere near us, the GMT should provide us with compelling evidence in the next twenty years.
The National Science Foundation was initially going to contribute heavily to the telescope but, since the United States Government has become indifferent to science and knowledge, other institutions have been forced to pick up the slack. The scope is being built by a cooperative effort between The University of Chicago, The University of Texas at Austin, The Australian National University, The Carnegie Institution for Science, Harvard University, The Korea Astronomy and Space Science Institute, the Smithsonian Institution, Texas A&M University, & The University of Arizona (so you can probably help out by donating to any of these institutions, particularly the lovable University of Chicago).
It has been a long time since we had a garden post here. In order to make the time pass more quickly until spring arrives and we have real flower gardening, here are some pictures of various beautiful sculpture gardens scattered across North America and Europe. They make we want to add some sculptures to my own backyard garden (which has a sphinx and a fu dog). Does anybody know where I could get a Janus statue and maybe some lamassus? Perhaps it’s time I broke out of this torpor and just carved a bunch of crazy mystical animals! Anyway enjoy the sculpture gardens…
This blog has featured replicas of two ancient sailing ships–the Greek trireme Olympias and the Norwegian Viking ship Dragon King Harald—however the prettiest modern replica of an ancient ship is a reconstruction of a much older vessel. The ship Min of the Desert was hand built by 4 men and 2 teenage boys in the modern Hamdi Lahma & Brothers shipyard in Rashid, Egypt (which was called Rosetta in classical times). The builders used traditional tools and original techniques to craft the Min after a sea-going Egyptian trade ship from 3500 years ago.
Archaeologists know a great deal about the boats which sailed the Nile–since they have the actual ships (which were preserved in tombs in order that Pharaohs could sail in the next world). However sea-faring ships were not preserved in the same way and only trace evidence from underwater archaeological sights survives. To build the Min, the modern shipwrights looked to river ships from tombs for technique, but they looked at ancient Egyptian art for a design. A 3,500-year-old bas relief from the pharaoh Hatshepsut ‘s funerary temple at Deir el-Bahri near Thebes, provided the basic design for the Min of the Desert.
The ships pictured on the bas relief were trade ships which participated in Hatshepsut ‘s trade expedition to Punt, which took place in the ninth year of her reign (Hatshepsut was a lady pharaoh who lived in the 15th century B.C. and reigned as the fifth pharaoh of the eighteenth dynasty). From the time of the old kingdom onward, Egyptians had launched expeditions to the land of Punt, a kingdom rich in gold, frankincense, myrrh, and exotic timber. Numerous ancient Egyptian sources mention Punt (which was a trade destination for the Egyptians for over a thousand years) but none actually mention where it is—apparently everyone back then just knew. The actual location has eluded Egyptologists for 150 years. To get to Punt, ships were carried in pieces across the desert to the Red Sea port of Saww. Then the vessels sailed on the Red Sea…to where? Modern day Somalia and Arabia are the best guesses, but the issue remains in doubt.
When completed Min of the Desert measured 20 meters (66 ft) long and nearly 5 meters (16 ft) wide with a cargo capacity of about 17 tons. Held together entirely by mortise-and-tenon joints, the ship proved to be surprisingly seaworthy and fast. Sailors rowed the Min in to position to raise the sail (a labor which required substantial physical strength) and then traveled along at speeds between 5 and 9 knots. The ship handled 25 knot winds and 3 meter swells with ease. The modern sailors were surprised by the excellence of the 3500 year old ship.
In the desolate desert 150 kilometers southwest of Cairo there is a fearsome arid valley (wadi) of cliffs, carved buttes, and sandblasted erratic boulders. The bleached landscape has an otherworldly emptiness as though it were located on a lifeless alien planet, though if you look closely, the desert is filled with austere furtive life like dorcas gazelles, tiny sand colored lizards, cobras, scorpions, and fennec foxes. The name of the place is even more otherworldly—“Wadi Al-Hitan” which is Arabic for “valley of the whales” and although the great smooth rocks buckling out of the sand might momentarily be taken for the backs of huge whales, the utter absence of the ocean (or of water of any kind) makes the name seem fanciful. The nearby Mount Garet Gohannam (which means mountain of hell because of the way it glows like flames at sunset) seems to be more aptly named.
However the name of Wadi Al-Hitan is remarkably literal–for the valley contains the remains of hundreds of huge ancient cetaceans which died in the Eocene and were fossilized in the yellowish sandstone. Forty million years ago the valley was a marine lagoon. Although the remains of numerous sirenians, sawfish, sharks, rays, sea turtles, marine crocodiles, sea snakes, and even swamp dwelling moeritheriums have been discovered in the wadi, the valley takes its name from the most spectacular and numerous fossils which belong to four different species of primitive whales. The most commonly discovered fossils belong to Dorudon, which was 3-5 meters long (9-15 feet) and fed on fish and mollusks, and to Basilosaurus, which was 15-22 meter (50-72 foot) and fed on everything else in the ocean.
Basilosaurus was first discovered in Louisiana in the early 19th century. Its immense size and serpentine form initially convinced naturalists that it was a marine reptile and they misnamed the creature Basilosaurus (which means “king lizard”). The mistake soon became obvious and Basilosaurus was classified among the Archaeoceti, a paraphyletic suborder of the cetaceans, however the giant kept its dinosaur name. Different species of Basilosaurus flourished in oceans worldwide during the wet, tropical Eocene and, even though they were obviously very adept at ocean living (indeed rising to the top of the food chain) the creatures betray vestiges of terrestrial living which modern whales have entirely dispensed with. Not only do Basilosaurus fossils have teeth and jaws which retain reatures from their artiodactyl ancestors, they also have tiny vestigial back legs a mere half meter in length (which would scarely help a 22 meter animal get around). Additionally Basilosaurus was different from modern whales in that it probably moved with eel-like horizontal thrashing of its long tail (modern whales move their flukes vertically). Basilosaurus probably did not dive very deeply, but moved about near the surface of the oceans hunting for smaller marine animals.
Although Wadi Al-Hitan was discovered by Europeans in 1902-1903, some archaeologists and anthropologists have speculated that it was known long before that and have been irresistibly drawn towards comparing basilosaurus with the giant crocodiles and earth spanning serpent gods which populate ancient Egyptian cosmology.
When I think of China, I tend to imagine coastal China or the Yangtze River valley—which is to say areas of tremendous human population density where neighbor lives smashed up against neighbor and black smokestacks belch poison smoke onto the churning masses. Yet China is truly vast and parts of the nation are among the least densely populated places on Earth. The great northwest deserts of China are a land of shifting sands, xeric scrubland, and nothingness. Yet the dry wasteland is home to one of the world’s rarest and fanciest leaping rodents.
The Long-eared Jerboa, Euchoreutes naso, is an insect-eating, long-jumping, mouse-like creature which lives in the deserts of China and Mongolia. The animal’s habits are largely unknown–since it is a master of stealth and also since it lives in such an unforgiving and desolate regions where biologists are infrequent guests. The long-eared jerboa is sufficiently distinct that it is classified in its own genus and its own subfamily. It is (self-evidently) notable for its long ears which it uses to hunt insects in the desert nights and to avoid predators.
The animal is lightweight with a mass of only 24 g (0.85 oz) to 38 g (1.3 oz) and its body is small, measuring from 70 mm (2.8 in) to 90 mm (3.5 in)—although its tail is just as long as its body so the whole creature measures up to 180 mm long (7 inches) if you count the tail. Like other jerboas, this species probably excavate burrows where they rest during the day. Because they are so enigmatic and poorly understood (and also so endearing), the long-eared jerboas are a kind of symbol of truly wild creatures and the little rodent was identified as one of the top-10 “focal species” in 2007 by the Evolutionarily Distinct and Globally Endangered (EDGE) project.
Tarim Lake was a salty lake which once covered more than 10,000 square kilometers (3,900 sq mi) in a dry region of Xinjiang, China. The Lake was formed because the Tarim River and the Shule River both emptied into an endorheic basin–a landlocked area which prevents the outflow of any water. Since the time of the Yuan Dynasty the region has been called Lop Nur— a Mongolian name which apparently means something like “lake of many converging water sources”. The name has become ironic: because of climate change, deforestation, and a series of ill-conceived dams, Lop Nur is now an inhospitable desert with a few small seasonal salt ponds. The region is today an arid wasteland.
Lop Nur boasts a complex history stretching back to before the Bronze Age and the region has been the site of a number of fascinating but mysterious archaeological finds. A number of exceptionally preserved mummies (known as the Tarim mummies) which date from 1900 BC to 200 BC intrigue scholars because of their Caucasian features and DNA. These inhabitants of the Tarim Basin probably spoke Tocharian, the eastern-most known Indo-European language. As history ebbed and flowed, the Tarim/Tocharian people became mixed with Uighurs, Kazaks, Kyrgyzs, and Han Chinese to form a vibrant culture.
Lop Nur is thus the site of one of the great lost cities from Chinese history. During the time of the Han Dynasty, a large oasis town now known as the Loulan Ancient City flourished by the lake and grew rich from its position along the Silk Road. But in the 7th century, due to a changing climate, the Loulan Ancient City vanished entirely destroyed by desertification, sandstorms, and other factors. It is believed that the deforestation of the swampy poplar forests around the lake may have been an important factor contributing to the swift decline. The region holds on to its treasures fiercely. Numerous archaeologists and treasure hunters have been killed by the dunes, quicksands, and flash floods of the desert including noted archaelogist Peng Jiamu, who disappeared in 1980, and the explorer Yu Chunshun, who died there in 1996. Because of its desolation and danger Lop Nar is also called the forbidden zone.
There are other even more compelling reasons that the region has that name. The Red army uses parts of the desolate and unpopulated evaporite wasteland as a testing ground (much in the manner the US Defence department makes use of certain desert regions Nevada). In 1964, Lop Nur was the site of the first successful thermonuclear fission test by the Peoples Republic of China, a project which was blandly codenamed “596″. Three years later in an exercise known as “Project Number 6” the Chinese military successfully tested a hydrogen bomb at the site thereby simultaneously demonstrating their power, scientific aplomb, and ability to craft boring secret names.
There are twenty extant species of armadillos–new world placental mammals covered with armored plates. The smallest of these armored creatures is the Pink Fairy Armadillo (Chlamyphorus truncates) which is only 9-12 centimeters in total length (about 4 or 5 inches). The diminutive creature weighs slightly more than 100 grams when mature and inhabits the central drylands of Argentina. It has multiple hard ring-like plates of delicate pink which it can close into a box form for protection (although its first defensive strategy is to dig into the ground). The animal has tiny eyes and a torpedo-like head for pushing into the sand. The portions of the Pink Fairy Armadillo not covered with plates are covered in dense white fur. Like the golden mole of Namibia, the pink fairy armadillo is a sand swimmer: the little animal agitates the fine, dry sand with its powerful claws and literally swims through the turbulence with its hard bullet shaped body. The armadillos are also like the golden mole in that they can lower their metabolism to levels unheard of among other placental mammals. However armadillos are not closely related to the golden mole—or indeed to any other placental mammals other than fellow Xenarthra (the sloths, armadillos, and anteaters). South America spent a long portion of geological time as an island and the mammals there had a long time to develop on their own. It is still not known whether Xenarthrans like the Pink Fairy Armadillo are truly Eutherians or whether they are the descendants of the ancestors of the Eutherians (sorry: the language of cladistics does not lend itself to eloquent explanations and all of the names sound like they come from a far-away planet—for example “Xenarthrans”).
I would like to tell you more about the Pink Fairy Armadillo, but I am unable to do so. Since it lives underground, the animal is rarely seen in the wild. It is even more unusual in captivity where it does not long survive the shocks and stresses of zoo living (additionally it seems unable to live on anything other than local invertebrates). This is unfortunate as it is believed that the Pink Fairy Armadillo is struggling in the wild. It is presumed to be declining in numbers–a victim to habitat loss from human activity. I used wiggle words like “believed” and “presumed” because nobody really has any idea about the actual populations of Pink Fairy Armadillos.
In the absence of real information here is a little gallery of Pink Fairy Armadillo artwork. Enjoy these pictures, it is profoundly unlikely you will ever see a real Pink Fairy Armadillo in the real world (which is sad because I find them curiously endearing). I particularly like the cartoon of the Pink Fairy Armadillo dreaming of transcendence into a mythical fairy being.
Yesterday I spent some time describing the Namib Desert (as well as giving a brief overview of the entire nation of Namibia). I did this not just because Namibia strikes me as one of the most striking landscapes on earth, but because the harsh habitat is home to a profoundly strange mammal, Grant’s Golden Mole (Eremitalpa granti), a solitary, nocturnal predator of the Nagib Desert. Grant’s golden mole lives primarily in the Namib Desert but ranges as far north as Angola and as far south as the arid dunes of South Africa.
The golden moles are already strange animals. The name “mole” is a misnomer: golden moles are not closely related to the true moles (which are insectivores) or to the marsupial moles of Australia. Their taxonomical classification is presently unclear but they seem to be most closely related the tenrecs, a group of insect eating primitive placental mammals. Tenrecs and golden moles both have unusual dentition (a critical feature to the taxonomist) and possess cloacas like birds. It has been speculated that tenrecs and golden moles are closely related to the first placental mammals, but this may be a mistake. It is also possible that the tenrecs resemble the ancestral placental mammal of long ago whereas golden moles have evolved features which uniquely suit their desert environments.
Grant’s golden mole is a particular anomaly since it is so profoundly suited for desert living (which may have to do with the great age of the Namib Desert). Grant’s golden mole does not make permanent burrows but literally swims through the sand. The creature has powerful claws for digging which have almost some to resemble “sand flippers”. It can move swiftly underground and detect its prey (termites, scorpions, and lizards) through its profoundly acute sense of touch. Its eyes have become vestigial and are covered with both skin and fur. Because it burrows through fine particles of sand, its coat is incredibly fine and dense, its nose is a leathery wedge, and its ears have shrunk to tiny, tiny openings.
Grant’s golden mole does not build burrows so it is not known how or where it raises its young. Because water is so scarce in the Namib Desert, the golden mole does not drink: its kidneys are hyper efficient. It also does not regulate its temperature in the manner of other mammals and it is capable of dropping into a suspended state during the days (when it digs deep down into the oxygen poor sand). Grant’s golden mole requires large swaths of sandy desert for hunting. It lives only on the shifting dunes. With such a lifestyle you would think that it has escaped trouble from humankind, but you would be wrong. The giant sand mines of Namibia are eating into its habitat and it is preyed on by feral cats. In so far as we know anything about its numbers, we believe it is threatened. Even in one of the most inhospitable places, humans are making inroads.
Try to imagine the Namib Desert, where a stormy foggy shoreline gives way quickly to endless bone-dry dunes of shifting golden sand. It is one of the starkest contrasts in the world’s geography: the fury of the cold waves is juxtaposed with the opposing starkness of the sun-pounded dunes.
The coastline where the Namib Desert runs up against the Atlantic is known as the skeleton coast both because it is a place where whalers and sealers once discarded the stripped carcasses of the marine mammals they killed in droves and because it is one of the world’s most treacherous coastlines. More than a thousand major modern wrecks dot the coast (where they mingle with countless older shipwrecks). Portuguese sailors trying to get around the horn of Africa to reach the riches of Asia called the area “the gates of hell.” A human powered craft can make its way through the pounding surf to the desolate coastline but it then becomes impossible to re-launch. Sailors shipwrecked on the Namib coast thus faced the daunting prospect of walking through a vast expanse of waterless desert. Before the modern era, most ship-wrecked souls did not escape and their skeletons soon became part of the landscape.
The desert is ancient. For more than 55 million years it has existed as a wasteland with almost no surface water. Since the end of the age of dinosaurs, the warm tropical air of the Hadley cell has intersected a cold oceanic current welling northward from Antarctica. But the region was arid long before that. West Gondwanaland shifted to its present position along the Tropic of Capricorn nearly 130 million years ago and has remained there since—a wallflower in the great dance of continents.
Namibia was a German colony during the colonial era. Unsurprisingly, the Germans made their Namibian colony the sight of the twentieth century’s first genocide when they tried to extinguish the unruly Herero and Nama peoples in 1904. The nation was seized by South Africa after the end of World War I but after many decades of gradual power shifting Namibia gained complete independence in 1990.
The Republic of Namibia is the second sparsest nation on earth with only 2.1 million people spread across a landscape roughly the size of Germany, Poland, the Czech republic, Belgium, Denmark, and the Netherlands combined (not that those nations should ever be combined!). It is one of the few stable multi-party democracies in Africa (maybe I should say the world). Namibia makes most of its money from mining uranium, gemstones, lead, tungsten, gold, tin, fluorspar, manganese, marble, copper and zinc. Natural gas can be found just off the coast (though it may prove challenging to drill there).
Why am I writing about this beautiful harsh anomaly of a nation? The unique and isolated geography of Namibia have made it a unique ecosystem of creatures capable of surviving the harsh desert environment (to say nothing of the creatures which team in the rich coastal waters). Desert dwelling creatures have had a long time to adapt to the hostile conditions of the world’s oldest desert. One of the most unique of all placental mammals is found in Namibia. I’ll address this bizarre fossorial hunter in my next post.