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Ancient Chinese Explorers

<p>
	If Kristof's supposition is correct, then this remote African outpost retains an echo of one of history's most astonishing episodes of maritime exploration.</p>
<p>
<figure class="richtext-image full-width">
<img alt="painting of zheng he" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/ancient-chinese-explorers-01.width-990_I04jWGC.jpg"/>
<figcaption>In the 15th century, Zheng He, seen here with one of his massive ships in a painting at a temple shrine in Malaysia, led seven enormous seafaring expeditions.
        
        <div class="credit">© Chris Hellier/Corbis</div>
</figcaption>
</figure>
</p>
<h3>
	An Oriental armada</h3>
<p>
	Six centuries ago, a mighty armada of Chinese ships crossed the China Sea, then ventured west to Ceylon, Arabia, and East Africa. The fleet consisted of giant nine-masted junks, escorted by dozens of supply ships, water tankers, transports for cavalry horses, and patrol boats. The armada's crew totaled more than 27,000 sailors and soldiers. The largest of the junks were said to be over 400 feet long and 150 feet wide. (The <em>Santa Maria,</em> Columbus's largest ship, was a mere 90 by 30 feet and his crew numbered only 90.)</p>
<p>
	Loaded with Chinese silk, porcelain, and lacquerware, the junks visited ports around the Indian Ocean. Here, Arab and African merchants exchanged the spices, ivory, medicines, rare woods, and pearls so eagerly sought by the Chinese imperial court.</p>
<p>
	Seven times, from 1405 to 1433, the treasure fleets set off for the unknown. These seven great expeditions brought a vast web of trading links—from Taiwan to the Persian Gulf—under Chinese imperial control. This took place half a century before the first Europeans, rounding the tip of Africa in frail Portuguese caravels, "discovered" the Indian Ocean.</p>
<p>
<figure class="richtext-image full-width">
<img alt="Santa Maria &amp; Nina ships" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/ancient-chinese-explorers-02.width-990_8ALz3He.jpg"/>
<figcaption>Columbus's ships <em>Santa Maria</em> (foreground) and <em>Nina</em> would have appeared pint-sized next to Zheng He's largest vessels.
        
        <div class="credit">© Dorling_Kindersley/iStockphoto</div>
</figcaption>
</figure>
</p>
<p>
	With unrivaled nautical technology and countless other inventions to their credit, the Chinese were now poised to expand their influence beyond India and Africa. Here was one of history's great turning points. Had the Chinese emperors continued their huge investments in the treasure fleets, there is little reason why they, rather than the Portuguese, Spanish, Dutch and British, should not have colonized the world. Yet less than a century later, all overseas trade was banned, and it became a capital offense to set sail from China in a multi-masted ship. What explains this astonishing reversal of policy?</p>
<h3>
	Roots of Chinese seapower</h3>
<p>
	The first Chinese oceangoing trade ships were built far back in the Song dynasty (c. 960-1270). But it was the subsequent Mongol emperors (the Yuan dynasty of c. 1271-1368) who commissioned the first imperial treasure fleets and founded trading posts in Sumatra, Ceylon, and southern India. When Marco Polo made his famous journey to the Mongol court, he described four-masted junks with 60 individual cabins for merchants, watertight bulkheads, and crews of up to 300.</p>
<p>
<figure class="richtext-image full-width">
<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/ancient-chinese-explorers-03.width-990_lzjTfg5.jpg"/>
<figcaption>Despite the strength and prosperity that marked their empire, Ming emperors deliberately chose not to try to colonize lands beyond the Middle Kingdom. Why?
        
        <div class="credit">Pierre Corrade</div>
</figcaption>
</figure>
</p>
<p>
	When the Han Chinese overthrew the Mongols and founded the Ming dynasty in the later 14th century, they took over the fleet and an already extensive trade network. The enterprising spirit of the Ming era reached a climax following the rebellion of the warrior prince Zhu Di, who usurped the throne in 1402. Disapproved of by the Confucian "establishment," Zhu Di put his trust in the worldly eunuchs who had always sought their fortunes in commerce. During his revolt, Zhu Di's right-hand man had been the Muslim eunuch Zheng He, whom he now appointed to command the treasure fleet.</p>
<blockquote>
	If accurate, these dimensions would signal the biggest wooden ships ever built.</blockquote>
<p>
	At the start of the first of Zheng He's epic voyages in 1403, it is said that 317 ships gathered in the port of Nanjing. As sociologist Janet Abu-Lughod notes, "The impressive show of force that paraded around the Indian Ocean during the first three decades of the 15th century was intended to signal the 'barbarian nations' that China had reassumed her rightful place in the firmament of nations—had once again become the 'Middle Kingdom' of the world."</p>
<h3>
	Treasure junks: fact or fiction?</h3>
<p>
	The Ming account of the voyages that followed strains credulity: "The ships which sail the Southern Sea are like houses. When their sails are spread they are like great clouds in the sky." Were the reported dimensions of the biggest galleons—over 400 feet long by 150 wide—gross exaggerations? If accurate, these dimensions would signal the biggest wooden ships ever built. Only the mightiest wooden warships of the Victorian age approached these lengths, and several of these vessels suffered from structural problems that required extensive internal iron supports to hold the hull together. No such structures are reported in the Chinese sources.</p>
<p>
<figure class="richtext-image full-width">
<img alt="Zheng He's ships" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/ancient-chinese-explorers-04.width-990_gKgWhER.jpg"/>
<figcaption>Zheng He's ships, as depicted in a Chinese woodblock print thought to date to the early 17th century
        
        <div class="credit">Courtesy of Instructional Resources Corporation, www.historypictures.com</div>
</figcaption>
</figure>
</p>
<p>
	However, in 1962, the rudderpost of a treasure ship was excavated in the ruins of one of the Ming boatyards in Nanjing. This timber was no less than 36 feet long. Reverse engineering using the proportions typical of a traditional junk indicated a hull length of around 500 feet.</p>
<p>
	Unfortunately, other archeological traces of this "golden age" of Chinese seafaring remain elusive. One of the most intensively studied wrecks, found at Quanzhou in 1973, dates from the earlier Song period; this substantial double-masted ship probably sank sometime in the 1270s. Its V-shaped hull is framed around a pine keel over 100 feet long and covered with a double layer of intricately fitted cedar planking, thus clearly indicating its oceangoing character. Inside, 13 compartments held the residue of an exotic cargo of spices, shells, and fragrant woods, much of it originating in east Africa (see <a href="/wgbh/nova/sultan/archeology.html" target="_top">Asia's Undersea Archeology</a>).</p>
<p>
	The Quanzhou wreck suggests that over a century before Zheng He's fabled voyages, the Chinese were already involved in ambitious trading exploits across the Indian Ocean. Even back then, their sturdy ships equaled the largest known European vessels of the period. By inventing watertight compartments and efficient "lugsails" that enabled them to steer close to the wind, Chinese shipbuilders remained ahead of the West in the following centuries.</p>
<p>
<figure class="richtext-image full-width">
<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/ancient-chinese-explorers-05.width-990_xK3lxl4.jpg"/>
<figcaption>Zheng He (1371-1433), the great Ming navigator
        
        <div class="credit">Courtesy of Instructional Resources Corporation, www.historypictures.com</div>
</figcaption>
</figure>
</p>
<h3>
	Exploits of the eunuch admiral</h3>
<p>
	Zheng He commemorated his adventures on a stone pillar discovered in Fujian province in the 1930s. His mission, according to the pillar, was to flaunt the might of Chinese power and collect tribute from the "barbarians from beyond the seas." On his first trip, leading more than 60 massive galleons, Zheng He visited what would later become Vietnam and reached the port of Calicut, India. On his return, he battled pirates and established massive warehouses in the Straits of Malacca for sorting all the goods accumulated on this and subsequent voyages.</p>
<blockquote>
	Landing at Somalia, he found himself offered such exotic items as "dragon saliva, incense, and golden amber."</blockquote>
<p>
	While voyaging to India, the ships encountered a ferocious hurricane. Zheng He prayed to the Taoist Goddess known as the Celestial Spouse. In response, a "divine light" shone at the tips of the mast, and the storm subsided. This heavenly sign—perhaps the static electrical phenomenon known as St. Elmo's fire—led Zheng He to believe that his missions were under special divine protection.</p>
<p>
	The emperor launched Zheng He's fourth and most ambitious voyage in January 1414. Its destination was Hormuz on the Persian Gulf, where artisans strung together exquisite pearls and merchants dealt in precious stones and metals. While Zheng He lingered in the city to amass treasure for the emperor, another branch of the fleet sailed to the kingdom of Bengal in present-day Bangladesh.</p>
<p>
<figure class="richtext-image full-width">
<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/ancient-chinese-explorers-06.width-990_fwB1ass.jpg"/>
<figcaption>To navigate throughout the Indian Ocean, Zheng He would have made use of the magnetic compass, invented in China during the Song dynasty.
        
        <div class="credit">© WGBH Educational Foundation</div>
</figcaption>
</figure>
</p>
<p>
	Here the travelers saw a giraffe that the east African potentate of Malindi had presented to the Bengal ruler. The Chinese persuaded their hosts to part with the giraffe as a gift to the emperor and to procure another like it from Africa. When the giraffe arrived at the court in Nanjing in 1415, the emperor's philosophers identified it, despite its pair of horns, as the fabled <em>chi'i-lin</em> or unicorn, an animal associated with an age of exceptional peace and prosperity. As the fleet's merchants laid treasures from Arabia and India at the feet of the emperor, this omen must surely have seemed fitting.</p>
<p>
	The initial diplomatic contact with Malindi now encouraged Zheng He to plan a direct trading voyage to eastern Africa. Landing at Somalia on the coast, he found himself offered such exotic items as "dragon saliva, incense, and golden amber." But even these substances paled before the extraordinary beasts that were loaded on board his ships. Lions, leopards, "camel-birds" (ostriches), "celestial horses" (zebras), and a "celestial stag" (oryx) were shipped back to the imperial court. Here officials showered congratulations on Zheng He and bowed low in awe before the divine creatures that accompanied him.</p>
<h3>
	End of an era</h3>
<p>
	Toward the end of his seventh voyage in 1433, the 62-year-old Zheng He died and was said to have been buried at sea. Although he had extended the wealth and power of China over a vast realm and is even today revered as a god in remote parts of Indonesia, the tide was already turning against foreign ventures.</p>
<p>
<figure class="richtext-image full-width">
<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/ancient-chinese-explorers-07.width-990_Tz7p2YO.jpg"/>
<figcaption>Impressive as they are, Chinese junks today are but pale shadows of medieval Chinese ships.
        
        <div class="credit">© WGBH Educational Foundation</div>
</figcaption>
</figure>
</p>
<p>
	The conservative Confucian faction now had the upper hand. In its worldview, it was improper to go abroad while one's parents were still alive. "Barbarian" nations were seen as offering little of value to add to the prosperity already present in the Middle Kingdom.</p>
<p>
	The renovation of the massive Grand Canal in 1411 offered a quicker and safer route for transporting grain than along the coast, so the demand for oceangoing vessels plummeted.</p>
<blockquote>
	Old men's folktales of shipwreck are among the few tangible relics of China's epic voyages of adventure.</blockquote>
<p>
	In addition, the threat of a new Mongol invasion drew military investment away from the expensive maintenance of the treasure fleets. By 1503 the navy had shrunk to one-tenth of its size in the early Ming. The final blow came in 1525 with the order to destroy all the larger classes of ships. China was now set on its centuries-long course of xenophobic isolation.</p>
<p>
	Historians can only speculate on how differently world history might have turned out had the Ming emperors pursued a vigorous colonial policy. As it is, porcelain shards washed up on the beaches of east Africa and old men's folktales of shipwreck are among the few tangible relics of China's epic voyages of adventure.</p>

A century before Europeans "discovered" the Indian Ocean, huge Chinese trading ships were sailing as far as Africa.

How Did the Red Baron Die?

<p>
<figure class="richtext-image full-width">
<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/red-baron-theories-01.width-990_eUA9tHK.jpg"/>
<figcaption>Who put the fatal bullet into the Red Baron as he closed in on Canadian Wilfrid May along the Somme River on April 21, 1918? Theories abound.
        
        <div class="credit">© WGBH/NOVA</div>
</figcaption>
</figure>
</p>
<h3>
	Mortally Wounded in Air Combat?</h3>
<p>
	The Royal Air Force (RAF) gave official credit for the Baron's death to No. 209 Squadron's Captain Roy Brown, whose combat report gives only the barest outline of the action: "Went back again and dived on pure red triplane which was firing on Lieut. May. I got a long burst into him and he went down vertical and was observed to crash by Lieut. Mellersh and Lieut. May."</p>
<p>
	In 1927, after gaining access to British Air Ministry files, Floyd Gibbons published a vivid account of Brown's victory in his best-selling popular book, <cite>The Red Knight of Germany.</cite> That same year, a first-person narrative of the action, "My Fight With Richthofen," was published in <cite>Liberty</cite> magazine. Although supposedly in Brown's own words, the article was clearly influenced by Gibbons and embroidered by <cite>Liberty</cite>'s copywriters.</p>
<p>
	While these popular accounts of Brown's attack are of doubtful value, his claim is supported by testimony from another 209 Squadron Captain, O. C. LeBoutillier, and from a few key eyewitnesses on the ground. However, most recent analysts conclude that the attack came at least a minute before the Baron's final crash, probably too early to have inflicted the fatal wound.</p>
<h3>
	Murdered On the Ground?</h3>
<p>
	In 1925, a New York-based magazine called <cite>The Progressive</cite> published an article titled "Richthofen Was Murdered." The article reported rumors circulating in Germany that Richthofen had landed unscathed and that Canadian soldiers had jumped from their trenches and killed the Baron before he could climb out of his triplane. The rumors may have begun when German pilots from the Baron's "circus" reported witnessing the triplane's relatively smooth crash landing; at first, this fueled hopes that the Baron had been captured alive, and later, the speculation that he had been murdered. However, eyewitness accounts by the first ground troops to reach the crash site make this highly implausible.</p>
<h3>
	Chasing Two Sopwith Camels?</h3>
<p>
	In accounts collected in the 1930s, at least three eyewitnesses claimed that the Baron was pursuing <em>two</em> Sopwith Camels at the time he was brought down by ground fire. One of the most detailed of these claims was by Sergeant A. G. Franklyn, who was in charge of an Australian antiaircraft battery and claims to have shot down the Baron with his Lewis gun. Subsequent research has suggested that Franklyn probably confused the Red Baron's demise with his battery's downing of a German airplane the day after the Baron's death in a slightly different location.</p>
<p>
<figure class="richtext-image full-width">
<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/red-baron-theories-02.width-990_JEp2CNW.jpg"/>
<figcaption>Various Allied gunners on the ground claimed to have shot the Baron down. To whom that honor truly belongs will likely never be known.
        
        <div class="credit">© WGBH/NOVA</div>
</figcaption>
</figure>
</p>
<h3>
	Shot Down by a Two-Seater?</h3>
<p>
	On the morning of April 21, 1918, the crew of two RE8 observation planes of the Australian Flying Corps' No. 3 Squadron reported a skirmish with two red-nosed Fokker triplanes. The squadron's commanding officer, Major D. V. J. Blake, submitted his squadron's report with other details implying that one of the attackers was Richthofen and that fire by an RE8 observer had brought the Baron down. However, the attack was at too high an altitude and too early to have been connected with the Baron's death. One explanation is that a pair of triplanes from the Baron's "circus," perhaps including the Baron himself, briefly dived on the two RE8s prior to encountering the Sopwith Camels of RAF No. 209 Squadron.</p>
<h3>
	An Unknown Rifleman on the Ground?</h3>
<p>
	P. J. Carisella and James W. Ryan's popular book <cite>Who Killed the Red Baron?</cite>, published in 1969, includes an account by Lieut. R. A. Wood of the 51st Battalion asserting that an unknown gunner from his unit brought down the Baron. "As soon as the planes had passed overhead my platoon opened up with rifle fire, and two sets of [Vickers] machine or Lewis guns on my left opened fire. Richthofen was seen to crash soon after one of these bursts." Another eyewitness interviewed in detail in 1975, Private V. J. Emery of 40th Battalion, supported Wood's claim. Emery believed that an unknown rifleman from Wood's platoon was in a better position to have fired the fatal shot than any of the other gunners in the area.</p>
<h3>
	Shot Down by a Machine Gunner on the Ground?</h3>
<p>
	NOVA's program focuses on the two best-known claims attributing Richthofen's death to machine gun fire from the ground. These were made by two different Australian antiaircraft crews who were stationed on the Morlancourt Ridge. In 1956, Gunner R. Buie, a Lewis gunner of the 53rd Battery, wrote to Australian newspapers about how he and Gunner W. J. Evans had opened fire on a German plane chasing a British one toward their position. "I started firing at the body of the German pilot directly through my peep sight," Buie wrote. "Fragments flew from the plane and it lessened speed. It came down a few hundred yards away." Most researchers reconstruct Buie and Evans' firing position as facing the oncoming triplane, making it unlikely that either could have fired the side-on shot that killed the Baron.</p>
<p>
	Sergeant C. B. Popkin, a Vickers gunner with the 24th Machine Gun Company, was in a more plausible position had he fired, as he claimed, when the Baron gave up chasing May and turned back toward the German lines. According to Popkin's statement recorded soon after the event: "As it came towards me, I opened fire a second time and observed at once that my fire took effect. The machine swerved, attempted to bank and make for the ground, and immediately crashed. The distance from the spot where the plane crashed and my gun was about 600 yards."</p>
<p>
	While Popkin's position seems the best match for the evidence of the Baron's wound, the long range and wide deflection angle required has led some to doubt the plausibility of his claim. Even Popkin himself had doubts; he told the <cite>Brisbane Courier</cite> in 1964 that "I am fairly certain it was my fire which caused the Baron to crash but it would be impossible to say definitely that I was responsible...As to pinpointing without doubt the man who fired the fatal shot the controversy will never actually be resolved."</p>
<p>
<figure class="richtext-image full-width">
<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/red-baron-theories-03.width-990_ERLyd4F.jpg"/>
<figcaption>The Somme River valley today, 85 years after the Baron's demise there launched decades of speculation into his true killer
        
        <div class="credit">© WGBH/NOVA</div>
</figcaption>
</figure>
</p>

Conflicting eyewitness accounts have led to many possible theories for the Red Baron's death.

Secrets of Viking Ships

<p>
<figure class="richtext-image full-width">
<img alt="Arial View of Ship" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/viking-ships-01.width-990_jzNTxJn.jpg"/>
<figcaption>With their invention of the longship, the Vikings spurred a literal sea change in medieval European affairs.
        
        <div class="credit">© Svergies TV</div>
</figcaption>
</figure>
</p>
<p>
	The <em>drekar,</em> or dragon-headed longships, were stealthy troop-carriers. They could cross the open oceans under sail and then switch to oars for lightning-fast hit-and-run attacks on undefended towns and monasteries. Far surpassing contemporary English or Frankish vessels in lightness and efficiency, longships carried Viking raiders from northern England to north Africa.</p>
<p>
	Viking expertise in naval craftsmanship soon led to the evolution of other types of ship. Among these were the <em>knarr,</em> or ocean-going cargo vessel, which facilitated far-flung trade networks and the colonization of Iceland, Greenland, and America. The <em>knarr</em> drew on similar design principles as the longship but was higher and wider in relation to its length and had only limited numbers of oars to assist with maneuvers in narrow channels. Cargo decks were installed fore and aft.</p>
<h3>
	Proof in the planking</h3>
<p>
	The secret of the Viking ship lay in its unique construction. Using a broad ax rather than a saw, expert woodworkers would first split oak tree trunks into long, thin planks. They then fastened the boards with iron nails to a single sturdy keel and then to each other, one plank overlapping the next. The Vikings gave shape to the hull using this "clinker" technique rather than the more conventional method of first building an inner skeleton for the hull.</p>
<p>
	Next, the boatbuilders affixed evenly spaced floor timbers to the keel and not to the hull; this insured resilience and flexibility. They then added crossbeams to provide a deck and rowing benches, and secured a massive beam along the keel to support the mast.</p>
<p>
<figure class="richtext-image full-width">
<img alt="Ship in Room" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/viking-ships-02.width-990_jyRwxkV.jpg"/>
<figcaption>Discovered in Norway in 1906, the Oseberg ship, the best preserved Viking ship ever found, reveals its Norse shipbuilders' graceful construction style.
        
        <div class="credit">© Svergies TV</div>
</figcaption>
</figure>
</p>
<p>
	The longships' light, economic construction was a major factor behind their success. Modern replicas have achieved speeds of up to 14 knots. In marked contrast to modern sailboats, the ships' lack of a big, vertical keel meant that they were highly maneuverable and could easily penetrate shallow surf and river estuaries. Seafarers steered using a single side rudder on the right, the 'starboard' or "steering board" side. (The term 'starboard' is thought to have originated in the Viking era.) They could also reef the square sails in strong winds and adjust them to permit rapid tacking.</p>
<h3>
	Preserved to the present</h3>
<p>
	Famous discoveries of Viking ships at Gokstad and Oseberg, Norway, in 1880 and 1906, respectively, established the classic image of the dragon-headed warship. Longships from both sites were preserved almost intact, with lavish carved decoration, in the waterlogged clay of royal burial mounds. Built around A.D. 890, three quarters of a century after the Oseberg ship, the Gokstad vessel shows great improvements in design, particularly in the sturdiness of the mast supports. Not surprisingly, this era, during which the Norse perfected longship design, coincides with the eruption of seaborne Viking raids on the monasteries and towns of Europe.</p>
<p>
<figure class="richtext-image full-width">
<img alt="ships in bay" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/viking-ships-03.width-990_suLfsfV.jpg"/>
<figcaption>Astoundingly, a veritable flotilla of sunken Viking vessels turned up on the grounds of the very museum being built to house other Viking boats.
        
        <div class="credit">© Svergies TV</div>
</figcaption>
</figure>
</p>
<p>
	The modern phase of Viking ship investigation began with the recovery of five vessels at Skuldelev in Roskilde fjord, Denmark, between 1957 and 1962. The excavation involved building a coffer dam around the ships, which Norsemen deliberately sunk in a desperate bid to barricade the fjord against invaders.</p>
<p>
	The major revelation at Skuldelev was the variety of the vessels, which ranged from a stocky cargo ship with a capacity of 24 tons to two sleek longships. The larger of the longships, measuring 95 feet in length, had made at least one successful crossing of the North Sea, for <a href="http://www.pbs.org/wgbh/nova/vikings/treering.html">tree-ring analysis</a> of its oak timbers revealed that they had been cut down around A.D. 1060-70 near Dublin, suggesting the presence of a major shipyard at this key Viking stronghold in Ireland.</p>
<p>
	Even more remarkable discoveries were to follow in 1996, when contractors began expanding Roskilde's waterfront museum, originally built to house the finds from Skuldelev. As astonishing as it sounds, no fewer than nine wrecked medieval ships eventually turned up in different spots around the building site, including one under the museum's car park.</p>
<h3>
	A stunning find</h3>
<p>
	The most striking discovery was the biggest longship yet found, 119 feet long, with room for at least 72 oars and a crew of 100. With its draft of only about three feet and a huge, 2,175-square-foot sail, the ship must have been swift and formidable. The excavators speculate that this ship, like the others in Roskilde harbor, may have gone down in a severe storm, then become hidden in silt. Tree-ring analysis of the high-quality oak used for its timbers suggests a construction date of around A.D. 1025.</p>
<p>
<figure class="richtext-image full-width">
<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/viking-ships-04.width-990_f2X64BS.jpg"/>
<figcaption>A detail from the Bayeux Tapestry, which commemorates the Norman invasion of England
        
        <div class="credit">© WGBH Educational Foundation</div>
</figcaption>
</figure>
</p>
<p>
	Countless sailing experiments with replica ships continue to confirm the excellence of Viking ship design. Much less is known about Viking navigation methods on the high seas, although one of the Icelandic sagas—narratives of Norse history and legends written in Iceland in the 12th and 13th centuries—includes sailing directions from Norway to Greenland that rely on distant landmarks and the presence of birds and whales to signal the position of land. The Vikings had no compass but undoubtedly steered by the sun and stars.</p>
<p>
	Did they have other aids? The sagas contain intriguing references to a <em>solarsteinn</em> or 'sunstone' used for navigation. Scholars believe it possible this stone was feldspar, a mineral found in Iceland that polarizes light. Theoretically, a polarizing stone might have helped indicate the direction of the sun when clouds obscured the view. Its practicality is doubtful, however, since it would require some blue sky to work and would thus have proved useless in total overcast.</p>
<p>
<figure class="richtext-image full-width">
<img alt="inside ship" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/viking-ships-05.width-990_6dZuIrc.jpg"/>
<figcaption>Did the Vikings, as the sagas suggest, really use a sun compass for navigation? If so, what form did it take?
        
        <div class="credit">© WGBH Educational Foundation</div>
</figcaption>
</figure>
</p>
<p>
	The evidence for a so-called "suncompass" is equally shaky. Some have viewed a fragment of a small wooden disk found in a Greenland monastery as a kind of bearing dial for finding north and south. The disk has a hole in its center, and the theory suggests that it originally fitted over a central pin or gnomon to cast a shadow. Markings around the edge of the disk could then have helped the navigator determine north-south. While similar modern devices do work successfully (as seen in the NOVA program "The Vikings"), many have questioned if the Greenland disc was actually used in this way. It is less than three inches across and the markings around the perimeter are so crudely carved as to make the interpretation doubtful.</p>
<h3>
	"The towered ships"</h3>
<p>
	The impression that a Viking fleet must have made under full sail can scarcely be imagined today, but a rhapsodizing monk at the monastery of St. Omer, France, tried his best to evoke the sailing of the royal Danish fleet in A.D. 1013:</p>
<p class="article-indent article-quote">
	When at length they were all gathered, they went on board the towered ships...On one side lions molded in gold were to be seen on the ships, on the other birds on the tops of the masts indicated by their movements the winds as they blew, or dragons of various kinds poured fire from their nostrils...But why should I now dwell upon the sides of the ships, which were not only painted with ornate colors but were covered with gold and silver figures?...The blue water, smitten by many oars, might be seen foaming far and wide, and the sunlight, cast back in the gleam of metal, spread a double radiance in the air.</p>

How did longships and other vessels help the Norsemen navigate distant waters so successfully?

Saving the Sphinx

<p>
<figure class="richtext-image full-width">
<img alt="Dr. Zahi Hawass in front of Sphinx" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/hawass-sphinx-01.width-990_WSgCACE.jpg"/>
<figcaption>"I think the main message that people should know is that the Sphinx is safe," says Dr. Zahi Hawass, Secretary General of Egypt's Supreme Council of Antiquities, seen here before the Sphinx in 2009.
        
        <div class="credit">Mark Bussell/Providence Pictures</div>
</figcaption>
</figure>
</p>
<p>
	Hawass recalls the painful moment: "The Sphinx for me is like my baby, so that moment, when I came and looked at the Sphinx, I felt like crying. I felt that the Sphinx was also crying. It was telling me that everyone who had come here to restore had made big mistakes."</p>
<p>
	Among the mistakes were extensive repairs in both the 1920s and the 1980s with modern cement and gypsum mortar, which generated cracks and stresses within the statue's relatively soft limestone. Over the next decade, Hawass supervised an ambitious campaign to remove the cement and gypsum and reverse the damage. His team experimented with many different "recipes" for a protective mortar that they could safely use to repair and consolidate the statue, ultimately settling on a mixture of quicklime and sand. The successful end of the campaign was marked by a symphony concert at the Sphinx in 1998 attended by President Mubarak.</p>
<p>
<figure class="richtext-image full-width">
<img alt="woman in front of Sphinx" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/hawass-sphinx-02.width-990_C1ru9fo.jpg"/>
<figcaption>A member of the Egyptian laser-scanning team at work
        
        <div class="credit">Mark Bussell/Providence Pictures</div>
</figcaption>
</figure>
</p>
<h2>
	A model for the future</h2>
<p>
	The celebration turned out to be premature. In 2007, new reports that the Sphinx was disintegrating hit the headlines. Sewage was being dumped in a nearby canal, raising concerns that polluted local groundwater was rising under the statue. As moisture creeps up through the porous limestone, it dissolves natural salts in the rock, which expand and crystallize when they reach the surface. This process attacks the weak middle layers of the Sphinx's body, causing the limestone to crumble and in some cases areas break away in big flakes, sometimes with an audible pop. A similar natural process during the Old Kingdom, when the climate was wetter than today, probably began breaking down the Sphinx's body soon after it was carved.</p>
<blockquote>
	"The Sphinx is not really for Egypt only. It is for everyone."</blockquote>
<p>
	So Hawass swung into action again, first launching a new effort to map the Sphinx with unprecedented precision. Under the direction of Dr. Walaa Sheta from Egypt's Mubarak City for Science and Technology, state-of-the-art laser ranging gear was hauled to the top of a 150-foot fire-truck ladder to trace the statue's back. From this lofty perch, the gear could map individual rocks on the back to within half an inch.</p>
<p>
	The result, completed in the spring of 2009, is a precise 3-D model of the statue that future restorers can consult on a computer to check for signs of damage or stress. This "beautifully accurate rendering of the Sphinx," says Hawass, "showing every piece of stone and recording the statue in three dimensions for the first time ... could be very important for conservation, because after doing the laser scanning, you can know what's new on the Sphinx and what should be restored. It's a record for the future."</p>
<p>
<figure class="richtext-image full-width">
<img alt="two men at base of Sphinx" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/hawass-sphinx-03.width-990_XJ5YEoI.jpg"/>
<figcaption>A crew pumps water from beneath the Sphinx, summer 2009
        
        <div class="credit">Courtesy Mark Lehner</div>
</figcaption>
</figure>
</p>
<h2>
	Constant care</h2>
<p>
	Meanwhile, to stop the groundwater threat, Hawass ordered the drilling of a series of test holes into the bedrock around the Sphinx. These revealed that the water table was 15 feet beneath the statue, posing a long-term threat of rising damp. So pumps were installed close to the Sphinx, and the source of groundwater from the local canal was diverted.</p>
<p>
	Commenting to NOVA about this latest success, Hawass says, "I think the main message that people should know is that the Sphinx is safe, and that we are like good physicians trying to look after it all the time. I really believe that it keeps all the secrets of our past, and if you ruin that, you will never have a future. And this is why I think that maybe God brought me to be the guardian of the Sphinx to save it for everyone. The Sphinx is not really for Egypt only. It is for everyone. And this is why, even when people see the Sphinx from far away, they can feel that magic."</p>

Zahi Hawass, head of Egypt's Supreme Council of Antiquities, has taken extraordinary steps to preserve the monument.

Neanderthals Defy Stereotypes

<p>
	Neanderthals died out just as our species—<em>Homo sapiens</em>—spreading from Africa, arrived around 40,000 years ago. If the claim is correct, it helps cast doubt on previous assumptions that Neanderthals lacked the abilities of modern humans to plan ahead, innovate, and communicate through language, art, and symbolism. There is a growing weight of evidence that we may have underestimated Neanderthal skills and behavior, and that they were not the lumbering, dim-witted cartoon cavemen of popular legend. At the same time, many questions remain contentious—for instance, whether Neanderthals had language, intentionally buried their dead, or regularly used mineral pigments to decorate their bodies.</p>
<h3>
	Ingenious and Industrious</h3>
<p>
	The claim investigated by NOVA is that Neanderthals invented a glue essential to producing their most formidable hunting weapon, a flaked stone spear tip fitted to a wooden shaft. They attached the stone to the shaft by winding animal sinew or some other type of binding around the joint and then smearing glue over it. Discoveries at Neanderthal sites in Syria and Romania show that, to obtain glue, they sometimes used natural deposits of bitumen or asphalt, in one case, fetched from over a dozen miles away. At the Syrian site, the bitumen had been heated up to make the thick liquid easier to apply.</p>
<p>
	{{cove--1--}}</p>
<p>
	At other sites, the Neanderthals subjected sticky substances to a much more elaborate process. Birch bark contains a tacky resin known as pitch that is impossible to extract simply by tapping into the tree, as with pinesap or maple syrup. Instead, the pitch must be separated from the bark by a process known as dry distillation. Chemists have discovered that distilling pitch from birch bark requires an oxygen-free environment and sustained temperatures of over 650° F. How could Neanderthals, with their Stone Age technology, have produced such conditions? If they really did master this complex process, it is hard to resist the conclusion that they must have had language and a sophisticated ability to think and plan ahead.</p>
<blockquote>
	Two small, hardened lumps of black material were found during the dig, one bearing a fingerprint and the other the impression of a wooden haft or handle.</blockquote>
<p>
	Evidence indicates that they successfully developed such a technique. The first discovery was made in 1963 at Kínigsaue, in then-East Germany. This was the site of an ancient lakeside hunting camp, from which Neanderthals had hunted now extinct Ice Age creatures such as mammoth and woolly rhino as well as red deer, horses, and reindeer. Two small, hardened lumps of black material were found during the dig, one bearing a fingerprint and the other the impression of a wooden haft or handle.</p>
<p>
<figure class="richtext-image full-width">
<img alt="One use of birch bark pitch glue" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/defy-stereotypes-02.width-990_7LF3QcG.jpg"/>
<figcaption>Neanderthals used their manufactured glue to secure stone spearheads to wooden shafts.
        
        <div class="credit">WGBH Educational Foundation</div>
</figcaption>
</figure>
</p>
<p>
	In 2001, the lumps were dated to at least 40,000 years ago and were shown to have the chemical signature of birch bark pitch produced by the dry distillation process. Much older evidence was found at the Campitello quarry in central Italy. Here, the remains of an extinct elephant lay close to two large lumps of black pitch, which covered the end of two stone flakes crafted in a typical Neanderthal style. The Campitello find dates back over 200,000 years, a remarkably early origin for this complex process. A third Neanderthal site at Inden-Altdorf, overlooking the Inde River in Germany and dating to around 128,000 to 115,000 years ago, features more than 80 stone tools flecked with black material, but the chemical analysis indicating that this was distilled pitch requires further confirmation.</p>
<h3>
	Before Their Time</h3>
<p>
	Pitch production only began on a large scale in Europe during the Middle Ages, around 1,000 years ago. Pieces of birch bark were typically rolled up inside a double-walled clay pot, which was sealed to exclude the air and placed in a kiln or fireplace. But the process was known in Europe long before that. The famous 5,300 year-old "Iceman," nicknamed ítzi—a naturally mummified body found in 1991 on a high mountain pass in the Tyrolean Alps—carried some 20 items of equipment, including a copper axe and flint-tipped arrows. Birch bark pitch was used to glue the axe to a handle carved from yew, while the arrowheads were bound and glued to shafts made from shoots of the <em>Viburnum</em> tree. In addition, ítzi carried some of his gear in two bark containers, so during ítzi's time, birch bark was evidently a versatile and important material.</p>
<p>
	Special clay vessels like those used in the Middle Ages have not been found in ítzi's era, nor did pottery exist in Neanderthal times. But the archaeologists at Inden-Altdorf found an important clue: upon analyzing the pitch smeared on Neanderthal tools at the site, they detected traces of potassium, sulfur, and calcium, evidence that the material had been directly exposed to fire and ash during its manufacture. After some practical experiments, the team proposed that the Neanderthals had invented the following procedure: first, wrap a long strip of birch bark around a small pebble so that it forms a cigar-shaped roll. Next, dig a narrow pit, then set light to one end of the roll and place the burning end at the bottom of the pit. In the confined space at the bottom of the pit, the smoldering bark quickly uses up oxygen and causes the pitch to "sweat," or condense, out of the roll of bark onto the surface of the pebble. While still hot, the pitch is a sticky liquid that can be used immediately as glue.</p>
<blockquote>
	"Neanderthals were very capable pyrotechnologists."</blockquote>
<p>
	Simple though it sounds in theory, the technique is highly challenging in practice. Although German experimental archaeologist Friedrich Palmer succeeded in earlier published experiments, in the NOVA program, he fails to produce more than a thin smear of pitch. In 2010, another team reported success by a variation on the technique: lay strips of bark on a flat stone surface, cover them with a couple of inches of sand to exclude oxygen, then build a fire on top. After a little over an hour, the team dug up the stone and found that enough pitch had dripped onto its surface to haft two or three spears or tools. However, the team succeeded easily on their first attempt only because they had a thermometer to judge if the fire was hot enough. Without such an aid, managing the fire proved very difficult, particularly in windy weather. Even with a windbreak, it required multiple attempts over many days to achieve success.</p>
<h3>
	Tight Tolerances</h3>
<p>
	Whatever technique is used, procuring pitch today with Stone Age methods obviously calls for careful attention and considerable skill and judgment. Too low a temperature, and the bark fails to produce any pitch; too high, and the bark becomes hard and brittle; with too much oxygen, the bark burns up. As the experimental tests have shown, the temperature of the fire must be constantly monitored in varying wind conditions, the birch bark must be buried correctly with oxygen excluded and removed from the fire at the right time. Archaeologist Wil Roebroeks, who witnessed Palmer's NOVA experiment, comments that its failure underscores the complexity of the process, which "goes to show that they [the Neanderthals] were very capable pyrotechnologists. We're still learning how they did it a quarter of a million years ago."</p>
<p>
	Roebroeks adds that the significance of the Neanderthal pitches should not be overblown. "After all, they were produced by hunter-gatherers who survived in western Eurasia for hundreds of thousands of years in a wide variety of environments, successfully exploiting a wide range of mammals and other resources...That they discovered a trick or two which we are unable to reproduce nowadays should not come as a surprise—unless of course one assumes that they were 'complete idiots,' lacking the flexibility and learning capacities of other primates."</p>
<p>
	While Roebroeks warns about making too much of the glue finds, for other archaeologists, the mere fact that Neanderthals could make multi-part tools and weapons argues that they were capable of planning in depth, coordinating several tasks at once, and conceptualizing past and future. No single category of evidence can decide the case for the status of the Neanderthal mind, but the intriguing story of birch bark pitch joins a growing list of discoveries that indicate we may have underestimated the closeness of our bond with our long-vanished relatives from the Ice Age.</p>

A type of manufactured glue found on stone tools suggests Neanderthals were more advanced than previously thought.

Battle Over Humanity’s Origins

<div class="related"></div>
<p>
 If you drive into the high veld country an hour northwest of Johannesburg, South Africa, you might not even notice when you cross into the Cradle of Humankind. The reason 180 square miles of open grasslands and scattered acacia and stinkwood trees have been given such a resonant honorific—it’s a World Heritage site, no less—lies mostly hidden underground, in the fossil-rich labyrinth of caves and sinkholes that riddle the limestone bedrock.
</p>
<p>
 On Thursday,
 <a href="http://www.pbs.org/wgbh/nova/next/evolution/lee-berger/">
  scientists announced
 </a>
 a new offering from the Cradle of Humankind: an ancient species called
 <i>
  Homo naledi
 </i>
 . Judging by the features of the fossil bones,
 <i>
  H. naledi
 </i>
 may indeed be one of the earliest members of our genus. So are these rolling hills truly the birthplace of humanity? Or do our deepest roots trace to the barren outcrops of East Africa, where the Leakeys made their groundbreaking discoveries and the famously bipedal ape Lucy was found?
</p>
<h2>
 The Southern Ape
</h2>
<p>
 South Africa’s initial claim to be humanity’s home goes back almost a hundred years. In 1924, anatomist Raymond Dart found a skull of a juvenile primate among a box of fossil-bearing rocks sent to him by the manager of a quarry at Taung, on the edge of the Kalahari Desert. Despite a tiny brain and other apelike features, the position of the opening at the base of the skull convinced Dart that the “Taung child” had walked upright like a human. He described the find as
 <i>
  Australopithecus africanus
 </i>
 (“southern ape of Africa”).
</p>
<p>
 For many years, the Taung child remained an isolated oddity that few scientists took seriously. An exception was Scottish doctor and paleontologist Robert Broom, who in 1936 discovered the first fragments of an adult australopithecine in Sterkfontein, today’s most visited cave in the Cradle of Humankind. Broom later found a nearly complete pelvis there, confirming that australopithecines were upright walkers. Broom planted the South African fossils firmly on the scientific map in a 1946 study, concluding that these ancestors were “nearly men, and were certainly closely allied to mankind.”
</p>
<div class="ad"></div>
<h2>
 East Side Story
</h2>
<p>
 At the time of Broom’s study, Louis Leakey, the Kenyan-born son of English missionaries, was struggling to vindicate his long-held belief that humanity was in fact rooted in his native East Africa. His quest finally bore fruit in 1959, when he and his wife, Mary, discovered an australopithecine skull in Tanzania’s Olduvai Gorge. A year later, the Leakeys found fossils of a more advanced species, seemingly a bridge from the australopithecines to us. They dubbed it
 <i>
  Homo habilis
 </i>
 , or “handy man,” after a scatter of stone tools close by.
</p>
<p>
 Aided by Leakey’s charismatic personality—and extensive coverage by
 <i>
  National Geographic
 </i>
 —the finds drew global attention. But what really moved the human origins spotlight to East Africa was the ability to accurately pin an age on the bones the Leakeys and others were uncovering. While neither the fossils nor the ancient sediments they were found in could be dated directly, volcanic ash layers interspersed between the sediments, like layers of icing in a cake, could be dated by the clocklike decay of their radioactive elements, fixing limits to the age of the fossil-rich sediments above or below. These volcanic ash deposits are a feature throughout the Great Rift Valley running north to south through East Africa, so the ability to date them proved crucial not only for Louis and Mary Leakey’s finds at Olduvai Gorge but also for the
 <a href="http://www.leakey.com/bios/richard-leakey">
  later discoveries
 </a>
 of their son Richard on the shores of Lake Turkana in Kenya, and for the team led by
 <a href="http://www.talkorigins.org/faqs/homs/djohanson.html">
  Donald Johanson
 </a>
 that discovered the Lucy skeleton in Hadar, in Ethiopia, in 1974.
</p>
<div class="pullquote">
<p>
 There are no neat layers of sediment with time stamps of volcanic ash in South African caves.
</p>
</div>
<p>
 Being able to date fossils enabled researchers to know how old they were in relationship to each other, connecting the discoveries emerging from the East African Rift into a phylogeny—a human family tree. Johanson and his collaborator
 <a href="https://ib.berkeley.edu/people/faculty/whitet">
  Tim White
 </a>
 assigned the Lucy skeleton and some other fossils to a new species,
 <i>
  Australopithecus afarensis
 </i>
 , dated to 3.2 million years ago. In their phylogeny,
 <i>
  A. afarensis
 </i>
 was the ancestor to
 <i>
  Homo habilis
 </i>
 , at a little under two million years old the most primitive member of our genus.
 <i>
  H. habilis
 </i>
 evolved into the younger, more advanced species
 <i>
  Homo erectus
 </i>
 , which in turn evolved into us. And Dart’s “southern ape,”
 <i>
  A. africanus
 </i>
 ? Along with some other species with robust skulls and teeth and gorilla-like crests on their craniums, it was assigned to an extinct side branch of the family tree.
</p>
<p>
 Firmly planted in East Africa, that version of the family tree cast a shadow over South Africa. Some new fossils were still emerging from the Cradle of Humankind, including a spectacular australopithecine skeleton dubbed Little Foot, more complete than any ever found, Lucy included. But it took its discoverer, Ron Clarke, 15 years to free it from the rock that entombed it deep in Sterkfontein cave.
</p>
<p>
 And like many other South Africa finds, Little Foot suffers from an uncertain date. There are no neat layers of sediment with time stamps of volcanic ash in South African caves. Slightly acidic rainwater percolates down through the limestone and etches out a chaos of chambers, fissures, shafts, and passages. Fossils might end up there by many routes, at many times, with little information on what happened when.
</p>
<div class="newsletter"></div>
<h2>
 The Plot Thickens
</h2>
<p>
 With so many challenges, the prospects for major breakthroughs in South Africa might seem unpromising. But recently, Lee Berger’s gift for finding astonishing fossil caches has pulled attention back to the Cradle of Humankind. At a site called Malapa in 2008, and now in the Rising Star cave ten miles away, his team has uncovered unprecedented numbers of fossil bones, adding two completely new species to the human family tree. Armed with their tantalizing mix of primitive and advanced features, Berger has become the champion of a resurgent South African claim to be the true birthplace of humankind.
</p>
<p>
 The role in human origins of the
 <i>
  Homo naledi
 </i>
 skeletons from Rising Star hangs in limbo, awaiting experimental techniques that might solve the question of their age. But Berger’s finds at Malapa, dubbed
 <i>
  Australopithecus sediba
 </i>
 , proved amenable to a technique called uranium-lead dating. At two million years, they are not as old as the earliest known fossil of the genus
 <i>
  Homo
 </i>
 in East Africa—a 2.8 million-year-old jaw found recently at a site called Ledi-Geraru in Ethiopia.
</p>
<p>
 Berger argues that regardless of its age,
 <i>
  A. sediba
 </i>
 stands as the best candidate for the most recent ancestor of our genus—we just haven’t yet found other, earlier fossils of its kind that predate the Ledi-Geraru jaw. That may sound like special pleading, but a
 <a href="http://rspb.royalsocietypublishing.org/content/282/1812/20150943">
  recent independent analysis
 </a>
 roping in data from 13 separate studies of hominin relationships came to the same conclusion. So does that rock the human cradle back toward South Africa? Not necessarily.
</p>
<p>
 “What it all seems to point to,” says paleontologist Brian Richmond, “is that although
 <i>
  sediba
 </i>
 probably shared a common ancestor with
 <i>
  Homo
 </i>
 much farther back in the past,
 <i>
  sediba
 </i>
 itself is too late to be directly on the human line. And whether that earlier common ancestor was in South Africa, or East Africa, or some entirely different part of Africa, we still can’t tell.”
</p>
<p>
 Whatever the verdict on Berger’s claims, Malapa and Rising Star have turned fresh eyes to the South African caves, and with each new find there, the scenario of our origins grows more intricate and complex. Meanwhile, some 97% of the continent has yet to be investigated by fossil hunters.
</p>
<p>
 “If you imagine our human origins as a 500-piece jigsaw puzzle,” says paleontologist Patricia Kramer, “then today we have maybe eight pieces near the east edge and four pieces from the south. We can grasp a bit of the pattern, but we’re nowhere near seeing the whole picture. And neither the east nor the south are more important than each other. We need both.”
</p>
<p>
 This article also appeared at
 <i>
<a href="http://news.nationalgeographic.com/2015/09/150911-hominin-hominid-berger-homo-naledi-fossils-ancestor-rising-star-human-origins/">
   National Geographic
  </a>
</i>
 .
</p>
<p>
 Photo credit: National Geographic Creative
</p>

<p>Two camps of archaeologists both claim their corner of Africa as humanity’s birthplace, but only one can be right.</p>

For over two decades, archaeologists have excavated the remains of Minoan houses and streets at Palaikastro in eastern Crete. In Bronze Age times, this was a substantial port with some 5,000 inhabitants.

Megatsunami May Not Have Wiped Out Europe’s First Great Civilization—So What Did?

<p>
 Around 3,500 years ago, a series of colossal explosions tore apart Thera, the largest of the five Santorini islands, today one of Greece’s most popular vacation spots. Current estimates suggest Thera’s eruption was the biggest volcanic cataclysm since the last Ice Age—ten times more powerful than Indonesia’s Krakatau in 1883, which triggered 140 feet-high tsunamis that killed at least 36,000 people. It must have been a terrifying experience for the Minoans. Thera’s blasts hurled a plume of ash and rock 20 miles high into the stratosphere, turning day into night.
</p>
<div class="related"></div>
<p>
 In 1939, leading Greek archaeologist Spyridon Marinatos was the first to suggest that Thera’s eruption doomed the Bronze Age Minoans, who created Europe’s first great civilization on the island of Crete, only 70 miles south. Ash flows and landslides may have triggered huge tsunamis, which could have swamped Cretan ports and wiped out the Minoan trading fleet.
</p>
<p>
 This mega-tsunami scenario has been an irresistible theme for popular writers and TV shows, since it seems to echo the story of Atlantis recounted by the philosopher Plato. In his fanciful tale, Atlantis, a giant island continent, was the center of an advanced civilization until the ocean swallowed it up in a single day and night. Perhaps the fate of the Minoans conjured up the Atlantis legend.
</p>
<p>
 Yet for decades, hard evidence for Thera’s impact on the Minoans has proven surprisingly elusive. And now, new findings cast doubt on the most compelling evidence for a devastating tsunami. Speaking this week at the American Institute of Archaeology meeting in New Orleans, geoarchaeologist Rachel Kulick of the University of Toronto announced the preliminary results of her fieldwork at Palaikastro, the site of a major Minoan town on Crete’s northeastern coast. Kulick’s work reopens the tsunami question and deepens the mystery surrounding Thera’s toll on the Minoans 3,500 years ago.
</p>
<div class="ad"></div>
<p>
 Palaikastro has been the focus of a major excavation project since the 1980s, supported by the British School at Athens and the Greek Ministry of Culture. The dig has unearthed seven blocks of the Minoan town, originally consisting of substantial two-story houses arranged in a tidy network of paved and drained streets. In 2001, the project invited geoarchaeologist Hendrik Bruins from Ben Gurion University to investigate an unusual soil layer about 300 feet northeast of the town, exposed in a sandy cliff side overlooking the present-day beach.
</p>
<p>
 When Bruins showed me this layer in 2006, I saw a thick layer containing a chaotic jumble of broken Minoan pottery, rocks, lumps of grey volcanic ash, and mashed-up animal teeth and bones. It looked as if a giant fist had smashed through an ancient neighborhood and then dumped the churned-up refuse on the beach with great force. While a violent storm surge could have been responsible, Bruins carried out careful tests that implicated a tsunami generated by Thera’s eruption. Radiocarbon dating of seashells and cattle bones, and chemical fingerprinting of the ash, all seemed to check out. What’s more, volcanic ash found in one of the streets in the Minoan town had evidently been washed in by water. With the help of computer simulations run by a leading tsunami expert, Bruins and his colleagues concluded that a giant wave—at least 30 feet high—had swept into the bay and deluged the town.
</p>
<figure class="richtext-image full-width">
<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/chaotic-layer-1-copy-2-e1421431873129.width-990_jrjxGkF.jpg"/>
<figcaption>A chaotic layer of animal bones, ash, and Minoan pottery exposed in the side of a cliff overlooking the beach at Palaikastro, identified by Hendrik Bruins and his colleagues as evidence for a massive tsunami.
        
    </figcaption>
</figure>
<p>
 This research, published in 2008 and 2009, won wide media attention. A leading expert on ancient volcanoes, Clive Oppenheimer of the University of Cambridge, described the work as meticulous and providing “a strong case.”
</p>
<p>
 But last summer, Rachel Kulick began questioning the study’s conclusions when she carried out an intensive analysis of soil blocks that had been saved from earlier digs in the Minoan town. If a tsunami had surged into the town, the same chaotic mixing of materials should have been obvious in these layers as in the cliffside at the beach. But under the microscope, the soil and ash layers looked very different. The ash from Thera had fallen in many fine layers just above the surface of the Minoan street. There were signs of gentle water action, perhaps by rain, but it had not been enough to disturb the ash layers or churn up the underlying paved street, as a tsunami almost certainly would have done.
</p>
<p>
 Another new soil section dug last summer told the same story. The location of this section—a major, 13-foot-deep sample—is particularly significant. It comes from a relatively low elevation compared with the rest of the site, so if a massive incoming wave had crashed across town, it should certainly have registered in the layers there.
</p>
<p>
 “But there is no evidence of a high energy water event in the section,” Kulick said, “only sand and gravel deposited by ordinary processes of drainage and erosion.” These negative findings from the town suggest there must be another explanation for the chaotic layers at the beach—perhaps a storm surge that disturbed Minoan refuse pits in a neighborhood now lost to the sea. Whatever had transpired to disrupt the remains at the coast had apparently not been powerful enough to penetrate inland and seriously damage the Minoan town.
</p>
<p>
 Next summer’s dig, directed by Carl Knappett of the University of Toronto, will provide another opportunity to check out these preliminary findings. But if Kulick is right, then Palaikastro would join a long list of at least 40 Minoan sites where efforts to identify tsunami layers have proven frustratingly elusive. The most convincing tsunami deposits yet found have come from the sea floor southeast of Santorini and from Bronze Age sites on the Turkish coast. So it’s possible that destructive waves were mainly focused eastward, away from Crete.
</p>
<p>
 A similar story applies to Thera’s plume of destructive ash. At the time of the eruption, the wind was evidently blowing toward the southeast, so much of Crete escaped the ash fall, while Palaikastro received a relatively light dusting of around two to four inches. However, even this amount would have had serious consequences, choking wells and poisoning pastures and olive groves. At Palaikastro, new wells were dug and parts of the site were abandoned and rebuilt. But what was Thera’s long-term impact on the Minoan world?
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<figure class="richtext-image full-width">
<img alt="" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/ash-1-copy-e1421432221451.width-990_uF6Y3Lz.jpg"/>
<figcaption>A microscope thin section of soil from the Palaikastro excavations shows a grey lump of ash from the Thera eruption.
        
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 According to one influential view, the traumatic effects of the eruption may have triggered religious and social unrest out of all proportion to any physical damage. Perhaps that led to increasing internal conflict and a gradual unraveling of the Minoan world. The emphasis is on “gradual,” since the record is clear that their brilliant civilization continued for another century or so; in fact, some of the most famous works of Minoan art and architecture post-date the eruption.
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 Science will continue to clarify the picture of what happened to the Minoans, but many archaeologists argue that we too readily underestimate the resilience of ancient peoples in the face of natural disaster and oversimplify the stories we tell about the fate of ancient peoples.
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 Photo credit: Evan Hadingham
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<p>Current estimates suggest Thera’s eruption, around 3,500 years ago, was the biggest volcanic cataclysm since the last Ice Age.</p>

Evan Hadingham

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