Thursday, 5 May 2016

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Monday, 2 May 2016

Dinosaur Die Out Was Gradual, Miserable, Painful

Dinosaurs gradually began to die out at least 40 million years before the devastating asteroid impact killed the rest in a dramatic way about 66 million years ago, concludes an extensive new study.

The research, outlined in the journal Proceedings of the National Academy of Sciences, is the first to incorporate phylogenetic information — meaning how species are related to one another — when studying speciation and extinction in dinosaurs.

The data provides evidence that things went from really bad to worse for most dinosaurs that did not evolve into birds.

PLAY VIDEO

Meet A Dino That Survived The Mass Extinction

Its name might be a tongue-twister, but Leikupal Laticauda has vaulted into the upper reaches of dinosaur stardom. Why? Because it lived after almost nothing else did.

“Some dinosaurs definitely would have been instantly killed in the impact, those in the vicinity of the impact site for instance; others may have perished in the tsunami caused by the blast,” lead author Manabu Sakamoto of the University of Reading’s School of Biological Sciences told Discovery News.

He continued, “The majority of the remaining dinosaurs all over the rest of the world would have likely starved to death as vegetation died out owing to the layer of ash that blacked out the sky (nuclear winter).”

A model created by Sakamoto and colleagues Michael Benton and Chris Venditti found that most dinosaur populations were already declining as early as 48–53 million years before the asteroid impact, which left the massive Chicxulub crater in Mexico. They say that the Cretaceous Period was a time of extreme geological and environmental changes.

“For instance,” Sakamoto said, “sea level was fluctuating, climate was shifting from a hot house to a global cooling, there were prolonged volcanic activities, and continents were breaking apart, establishing the main continents we have today.”

He explained that the supercontinent breakup would have resulted in less available land for dinosaurs to use for migration, which previously helped to fuel the evolution of new species. Climate change, both then and now, could induce major environmental and ecological shifts.

Sea level rise turned out to be more complex. Initially, it favored the evolution of more dinosaur species, but smaller land areas eventually restricted population growth.

Our ancestors, the early mammals, could have posed a big threat to dinos as well.

“Another possibility is that mammals, which were small rodent-like creatures at that time, were in some way contributing to the dinosaur’s downfall,” Benton, a professor of vertebrate paleontology at the University of Bristol, told Discovery News. “Recent studies show evidence that mammals were on the rise prior to the K-Pg (extinction) event, so this scenario would be consistent with our finding.”

Venditti, from the University of Reading, added that mammals might have outcompeted dinosaurs for resources, eaten their eggs, spread diseases or caused other problems for the once mighty dinos.

Aside from the dinosaur lineage that evolved to become birds, two other major groups of dinosaurs — the plant-eating hadrosaurs and ceratopsians — remained strong until the asteroid struck. Sakamoto explained that these dinos acquired specialized jaw structures that allowed them to process plant foods efficiently.

Paleontologist Steve Brusatte from the University of Edinburgh’s School of GeoSciences said the new study is an impressive take on “a subject that has been studied to death.”

"Cretaceous dinosaurs were evolving into fewer new species, and going extinct at a faster rate, than earlier dinosaurs,” said Brusatte. But he does not think that dinosaurs were doomed to extinction before 66 million years ago.

“The asteroid hit at a time when dinosaurs had already been around for a long time, and had already endured their really prolific periods of evolution,” Brusatte said. “But the way I see it, the dinosaur extinction still came down to the asteroid. No asteroid, no extinction."

There is an eerie footnote regarding lessons learned from the extinction of dinosaurs, and other animals that bit the dust after the asteroid hit. Any group of animals that is under a prolonged period of decline can be wiped out, should there be catastrophic event.

Sakamoto said, “This means that if some major catastrophe hits, then it is highly possible that whole groups of animals could be completely wiped off the face of the Earth.”

New Titanosaur: Big Body, Small Brain, Major A

CARNEGIE MUSEUM OF NATURAL HISTORY

A new titanosaur dig includes one of the best dinosaur skulls ever discovered, allowing researchers to reconstruct everything from the dino’s intellect -- or lack thereof -- to its senses and head posture.

Named Sarmientosaurus musacchioi, the new, small-brained dino had good eyesight, hearing tuned to low frequencies, and habitually held its head with its snout facing downward, according to a paper published in the journal PLOS ONE. The head was at the end of a long neck and featured a mouth full of sharp teeth.

PLAY VIDEO

Meet A Dino That Survived The Mass Extinction

Its name might be a tongue-twister, but Leikupal Laticauda has vaulted into the upper reaches of dinosaur stardom. Why? Because it lived after almost nothing else did.

DCI

The researchers believe that the plant-eating dinosaur lived life basically like a giant weed whacker, sweeping its neck over the ground to find plants that it would grab, but not chew.

“Sarmientosaurus had powerful teeth … but those teeth did not chew,” lead author Rubén Martínez of the Laboratorio de Paleovertebrados of the Universidad Nacional de la Patagonia San Juan Bosco told Discovery News. “(The teeth) would only cut the leaves and the dinosaur would eat them with almost no chewing.”

Co-author Lawrence Witmer of the Ohio University Heritage College of Osteopathic Medicine added that the dinosaur “had a large feeding envelope. When you’re as large as these sauropods were, being able to scarf down a lot of food without having to move saves a lot of energy.”

Witmer estimates that the dinosaur, which lived roughly 95 million years ago, was about 40–50 feet long and weighed 8–12 tons. He and his colleagues consider it to have been a modest-sized titanosaur, given that others could grow to 90 feet in length and weigh as much as 50 tons. They were the largest animals ever to walk the earth.

The new species was excavated in southern Chubut Province, Argentina, near the town of Sarmiento, for which the dino was named. The species name also honors the late paleontologist Eduardo Musacchio, who was a friend of Martínez and other members of the team.

Of the 60 plus species of titanosaur that have been discovered so far, only four are represented by nearly or even reasonably complete skulls. They include Nemegtosaurus, Rapetosaurus, Tapuiasaurus, and now, possibly with the best preserved skull of all, Sarmientosaurus.

The dino certainly did not have a lot of brain matter to weigh down its head. The researchers estimate that the creature's brain was the size of a lime. Witmer said that “Sarmientosaurus certainly was no Einstein and was governed mostly by instinct. It probably had enough intelligence to have some fairly complicated behaviors, but this was not a clever animal by any means.”A new titanosaur dig includes one of the best dinosaur skulls ever discovered, allowing researchers to reconstruct everything from the dino’s intellect -- or lack thereof -- to its senses and head posture.

PLAY VIDEO

Meet A Dino That Survived The Mass Extinction

Its name might be a tongue-twister, but Leikupal Laticauda has vaulted into the upper reaches of dinosaur stardom. Why? Because it lived after almost nothing else did.

DCI

The researchers believe that the plant-eating dinosaur lived life basically like a giant weed whacker, sweeping its neck over the ground to find plants that it would grab, but not chew.

At least it could see and hear predators, like the meat-eating Megaraptor. Its cochlear duct was different from that of most other known titanosaurs, and enabled it to hear low-frequency sounds spread out over long distances. Witmer said the ability “could have helped the animals keep track of others in the herd as they spread out over the countryside.”

He added that it might have been a primitive trait inherited from its ancestors. Sarmientosaurus appears to have been an intermediate species on the titanosaur family tree, providing a unique glimpse at evolution in action when compared with additional dinosaurs in the group.

PLAY VIDEO

Meet A Dino That Survived The Mass Extinction

Its name might be a tongue-twister, but Leikupal Laticauda has vaulted into the upper reaches of dinosaur stardom. Why? Because it lived after almost nothing else did.

DCI

The dinosaur’s well-preserved inner ear, revealed via CT scanning, reveals that it habitually held its snout pointing downward with its eyes directed forward.

As for its long neck, Martínez said that the bones in it were extremely light and nearly hollow with up to 80 percent air.

It's the first non-bird dinosaur to preserve a bizarre structure in the neck that the researchers interpret to have been a long bony tendon. The scientists support the widely held view, however, that birds evolved from two-legged, meat-eating dinosaurs similar to Velociraptor and not from large plant-eaters like Sarmientosaurus.

They suspect that other plant-eating dinosaurs, known as sauropods, had the bony tendon, but that, for some reason, it didn't fossilize in them the way that it did in the Sarmientosaurus remains.

Paleontologist Matt Lamanna of the Carnegie Museum of Natural History told Discovery News that five new dinosaur species have been found so far at the site in Argentina, called Estancia Laguna Palacios. They include Notohypsilophodon (a fast-running plant eater), Aniksosaurus (a small meat eater thought to have roamed in packs or herds), Katepensaurus (Lamanna called it “a super-weird, probably broad-snouted and toothy low-browsing sauropod,”) an as-of-yet unnamed new abelisaurid (“relative of the famous horned, bulldog-faced Carnotaurus and Majungasaurus”) and now Sarmientosaurus.

Lamanna said that all “came from an area of just a few square miles. It’s an awesome place.”

Snoring Lizards Reveal Sleep Predates Dinosaurs

APR 28, 2016 02:01 PM ET // BY JENNIFER VIEGAS

Owners of pet lizards for years have anecdotally reported that their reptilian friends snore, appear to dream, and seem to enjoy snoozing just as we do, and now new research finds that reptiles do indeed experience the same sleep states of mammals and birds.

Before, it was thought that only birds, humans and other mammals went through rapid eye movement sleep (REM) and slow-wave sleep (SWS) as they snoozed, but the new findings, published in the journal Science, suggest that these sleep patterns evolved in the common ancestor of all such animals more than 300 million years ago.

By extension, it is then likely that today’s reptiles dream, and that many long-extinct animals such as dinosaurs did so as well.

“Dreaming, like sleep, consciousness, language, pain etc. are all concepts or phenomena that were first experienced and described in a self-referential manner by humans, assigned a word and implicitly considered as uniquely human,” senior author Gilles Laurent, director of the Max Planck Institute for Brain Research, told Discovery News.

“But if you think as a biologist about these phenomena, accept that most of them probably did not drop from the sky onto the first human being, but rather result from some slow evolutionary process, then we can start thinking about dreams as patterns of neuronal activity in the brain during sleep that are at least partly built up from past experience,” he added. “If you are ready to accept that bits of neuronal playback in certain brain areas during sleep can be called dreams, then I’ll bet that lizards dream.”

Scientists for decades tried to detect sleep patterns in reptiles by placing electrodes on the surface of the animals’ brains, similar to doing an EEG. Laurent and his team took this a step further, by implanting probes right into the brains of five bearded dragons (lizards). As a result, the researchers were better able to record the sleep patterns and to match them to eye movements.

Animals Grab Some Shut-Eye on World Sleep Day: Photos

Humans go through four or five 60 to 90 minute SWS-REM cycles on average every night, but the lizards experienced about 350 80-second cycles. Rest is unaffected, Laurent said, as the two sleep cycles run together, just as they do in humans. The individual is basically unaware that all of this brain wave change is happening.

“Among mammals, there tends to be some relationship between animal size and length of sleep cycle,” he said. “It is not absolute, but is statistically true. For example, the human sleep cycle is about 60–90 minutes, while it is 30 minutes for cats and 15 minutes for rats.”

Even insects and arachnids like spiders sleep, but it is unclear if they experience REM and SWS sleep patterns. Some animals rest, but do not technically sleep.

Laurent explained, “Multicellular animals without brains, such as sponges and jellyfish…most likely do not express ‘brain sleep’ both by definition since they lack a brain and because REM and SWS require certain neural circuits that, as far as we know, they lack.”

Even for these creatures, prior amounts of rest, temperature shifts and other environmental factors seem to affect rest, which in multicellular animals without brains probably is expressed through their circadian rhythms, otherwise known as their internal “body clocks.”

As for now-extinct dinosaurs, Laurent said that “it seems likely they expressed REM and SWS.” They therefore probably dreamed and consolidated their memories as they slept in a way that was at least somewhat similar to how we and many other animals do so today.

Thanos Siapas, a professor of computation and neural systems at Caltech, told Discovery News that the new study “is a truly groundbreaking paper that sheds new light into how the architecture of sleep evolved. The data and analysis are very compelling and suggest an ancient origin of the two alternating stages of sleep.”

Siapas and the researchers were surprised that the sleep patterns detected in the lizards originated from different parts of the brain than expected, based on what happens in mammals and birds. Siapas hopes that future research will explore why this occurs, clarifying the functions of those brain regions.

Then there is what Laurent called “the $64 million dollar question”: Why and how did sleep evolved in the first place?

“We do not know now, and this is a fascinating question,” he said. “Did it evolve as something completely different, and evolve into what we know today? It is too early to say.”

GALLERY

DinosaurBloodandBoneCellsFound:Photos

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Wednesday, 6 April 2016

Dinosaurs

The prehistoric reptiles known as dinosaurs arose during the Middle to Late Triassic Period of the Mesozoic Era, some 230 million years ago. They were members of a subclass of reptiles called the arc

Scientists first began studying dinosaurs during the 1820s, when they discovered the bones of a large land reptile they dubbed a Megalosaurus (“big lizard”) buried in the English countryside. In 1842, Sir Richard Owen, Britain’s leading paleontologist, first coined the term “dinosaur.” Owen had examined bones from three different creatures–Megalosaurus, Iguanadon (“iguana tooth”) and Hylaeosaurus (“woodland lizard”). Each of them lived on land, was larger than any living reptile, walked with their legs directly beneath their bodies instead of out to the sides and had three more vertebrae in their hips than other known reptiles. Using this information, Owen determined that the three formed a special group of reptiles, which he named Dinosauria. The word comes from the ancient Greek word deinos (“terrible”) and sauros (“lizard” or “reptile”).

Since then, dinosaur fossils have been found all over the world and studied by paleontologists to find out more about the many different types of these creatures that existed. Scientists have traditionally divided the dinosaur group into two orders: the “bird-hipped” Ornithischia and the “lizard-hipped” Saurischia. From there, dinosaurs have been broken down into numerous genera (e.g. Tyrannosaurus or Triceratops) and each genus into one or more species. Some dinosaurs were bipedal, which means they walked on two legs. Some walked on four legs (quadrupedal), and some were able to switch between these two walking styles. Some dinosaurs were covered with a type of body armor, and some probably had feathers, like their modern bird relatives. Some moved quickly, while others were lumbering and slow. Most dinosaurs were herbivores, or plant-eaters, but some were carnivorous and hunted or scavenged other dinosaurs in order to survive.

At the time the dinosaurs arose, all of the Earth’s continents were connected together in one land mass, now known as Pangaea, and surrounded by one enormous ocean. Pangaea began to break apart into separate continents during the Early Jurassic Period (around 200 million years ago), and dinosaurs would have seen great changes in the world in which they lived over the course of their existence. Dinosaurs mysteriously disappeared at the end of the Cretaceous Period, around 65 million years ago. Many other types of animals, as well as many species of plants, died out around the same time, and numerous competing theories exist as to what caused this mass extinction. In addition to the great volcanic or tectonic activity that was occurring around that time, scientists have also discovered that a giant asteroid hit Earth about 65.5 million years ago, landing with the force of 180 trillion tons of TNT and spreading an enormous amount of ash all over the Earth’s surface. Deprived of water and sunlight, plants and algae would have died, killing off the planet’s herbivores; after a period of surviving on the carcasses of these herbivores, carnivores would have died out as well.

Despite the fact that dinosaurs no longer walk the Earth as they did during the Mesozoic Era, unmistakable traces of these enormous reptiles can be identified in their modern-day descendants: birds. Dinosaurs also live on in the study of paleontology, and new information about them is constantly being uncovered. Finally, judging from their frequent appearances in the movies and on television, dinosaurs have a firm hold in the popular imagination, one realm in which they show no danger of becoming extinct.

Cannibal Clues Worsen Tyrannosaurus Rex’s Bad Rap

NOVEMBER 5, 2010 By Jennie Cohen

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As if its reputation weren't bad enough already, scientists have unearthed new evidence that Tyrannosaurus rex was one of fiercest predators the world has ever seen. It turns out the 7-ton, 13-foot-tall monster may have had a taste for its own kind.

Meals were a gruesome production for Tyrannosaurus rex, one of the largest—and toothiest—creatures to ever stalk the earth. For the most part, the king of dinosaurs probably subsisted on its slower, smaller, vegetarian brethren, such as duck-billed hadrosaurs like Edmontosaurus and horned ceratopsians like Triceratops. It used its incredible speed and massive jaw to hunt and slay its victims, but it also wasn’t above scavenging for dead animals. Some scientists have even theorized that T. rex poisoned its struggling prey with toxic saliva, much like the modern-day Komodo dragon.

According to a recent study, T. rex’s rather brutal feeding patterns may also have included one of humanity’s most unspeakable taboos: cannibalism. Paleontologist Nicholas Longrich of Yale University discovered giant tooth marks half an inch deep in arm and foot bones from Tyrannosaurus rex fossils found in western North America and dated to the late Maastrichtian period. Given the size and shape of the gouges, another T. rex is the only possible culprit.

“They’re the kind of marks that any big carnivore could have made, but T. rex was the only big carnivore in western North America 65 million years ago,” Longrich explained in a statement.

Writing in the October 15 issue of the journal PLoS ONE, Longrich and his colleagues said it was unlikely that the gashes resulted from claw-to-claw combat, which scientists believe was common behavior for Tyrannosaurus rex. Battling dinosaurs would probably have lunged for each other’s more vulnerable areas, such as the head and flanks, rather than the feet and arms. Instead, the researchers suggested, a hungry Tyrannosaurus probably came across the carcass of another while scavenging for food. Alternatively, the victor of a violent intraspecies squabble may have celebrated by eating its dead opponent, toes and all.

The researchers found four examples of T. rex cannibalism within a small sample of tooth-marked bones, an indication that the practice was rampant rather than a last resort in desperate times. (In other words, there’s no evidence of a dinosaur Donner Party.) This finding is hardly surprising: In 2007, a team of scientists made a compelling case for cannibalism in another theropod, Majungasaurus, which existed several million years before Tyrannosaurus.

Today, cannibalism occurs in every corner of the animal kingdom, especially among large carnivores such as bears, hyenas and alligators. Smaller critters do it too, including scorpions, rattlesnakes and, perhaps most notoriously, female praying mantises, which decapitate their mates during sex. For some species, cannibalism is so instinctual it starts before birth: Sand tiger sharks, for instance, are known to devour their siblings while still in the womb.

The study is significant because it sheds new light on the diets and feeding habits not only of Tyrannosaurus rex but also of other gigantic predators that left their massive footprint in the fossil record. “Given that cannibalism is known in Tyrannosaurus, Majungatholus and many extant, large-bodied carnivores, this behavior is likely to have been widespread in large, carnivorous dinosaurs,” the researchers wrote.

Mass Extinctions

What Causes Animal Die-Offs?

More than 90 percent of all organisms that have ever lived on Earth are extinct. As new species evolve to fit ever changing ecological niches, older species fade away. But the rate of extinction is far from constant. At least a handful of times in the last 500 million years, 50 to more than 90 percent of all species on Earth have disappeared in a geological blink of the eye.

Though these mass extinctions are deadly events, they open up the planet for new life-forms to emerge. Dinosaurs appeared after one of the biggest mass extinction events on Earth, the Permian-Triassic extinction about 250 million years ago. The most studied mass extinction, between the Cretaceous and Paleogene periods about 65 million years ago, killed off the dinosaurs and made room for mammals to rapidly diversify and evolve.

The causes of these mass extinction events are unsolved mysteries, though volcanic eruptions and the impacts of large asteroids or comets are prime suspects in many of the cases. Both would eject tons of debris into the atmosphere, darkening the skies for at least months on end. Starved of sunlight, plants and plant-eating creatures would quickly die. Space rocks and volcanoes could also unleash toxic and heat-trapping gases that—once the dust settled—enable runaway global warming.

An extraterrestrial impact is most closely linked to the Cretaceous extinction event. A huge crater off Mexico's Yucatán Peninsula is dated to about 65 million years ago, coinciding with the extinction. Global warming fueled by volcanic eruptions at the Deccan Flats in India may also have aggravated the event. Whatever the cause, dinosaurs, as well as about half of all species on the planet, went extinct.

Massive floods of lava erupting from the central Atlantic magmatic province about 200 million years ago may explain the Triassic-Jurassic extinction. About 20 percent of all marine families went extinct, as well as most mammal-like creatures, many large amphibians, and all non-dinosaur archosaurs. An asteroid impact is another possible cause of the extinction, though a telltale crater has yet to be found.

Largest Ever Die-Off

The Permian-Triassic extinction event about 250 million years ago was the deadliest: More than 90 percent of all species perished. Many scientists believe an asteroid or comet triggered the massive die-off, but, again, no crater has been found. Another strong contender is flood volcanism from the Siberian Traps, a large igneous province in Russia. Impact-triggered volcanism is yet another possibility.

Starting about 360 million years ago, a drawn-out event eliminated about 70 percent of all marine species from Earth over a span of perhaps 20 million years. Pulses, each lasting 100,000 to 300,000 years, are noted within the larger lateDevonian extinction. Insects, plants, and the first proto-amphibians were on land by then, though the extinctions dealt landlubbers a severe setback.

The Ordovician-Silurian extinction, about 440 million years ago, involved massive glaciations that locked up much of the world's water as ice and caused sea levels to drop precipitously. The event took its hardest toll on marine organisms such as shelled brachiopods, eel-like conodonts, and the trilobites.

Happening Now?

Today, many scientists think the evidence indicates a sixth mass extinction is under way. The blame for this one, perhaps the fastest in Earth's history, falls firmly on the shoulders of humans. By the year 2100, human activities such as pollution, land clearing, and overfishing may have driven more than half of the world's marine and land species to extinction.

http://science.nationalgeographic.com/science/prehistoric-world/mass-extinction/

Dinosaur Extinction

Sixty-five million years ago the last of the non-avian dinosaurs went extinct. So too did the giant mosasaurs and plesiosaurs in the seas and the pterosaurs in the skies. Plankton, the base of the ocean food chain, took a hard hit. Many families of brachiopods and sea sponges disappeared. The remaining hard-shelled ammonites vanished. Shark diversity shriveled. Most vegetation withered. In all, more than half of the world's species were obliterated.

What caused this mass extinction that marks the end of the Cretaceous and the beginning of the Paleogene? Scientists have yet to find an answer. The one that does must explain why these animals died while most mammals, turtles, crocodiles, salamanders, and frogs survived. Birds escaped. So did snails, bivalves, sea stars (starfish), and sea urchins. Even hardy plants able to weather climate extremes fared OK.

Scientists tend to huddle around one of two hypotheses that may explain the Cretaceous extinction: an extraterrestrial impact, such as an asteroid or comet, or a massive bout of volcanism. Either scenario would have choked the skies with debris that starved the Earth of the sun's energy, throwing a wrench in photosynthesis and sending destruction up and down the food chain. Once the dust settled, greenhouse gases locked in the atmosphere would have caused the temperature to soar, a swift climate swing to topple much of the life that survived the prolonged darkness.

Asteroid or Volcanoes?

The extraterrestrial impact theory stems from the discovery that a layer of rock dated precisely to the extinction event is rich in the metal iridium. This layer is found all over the world, on land and in the oceans. Iridium is rare on Earth but it's found in meteorites at the same concentration as in this layer. This led scientists to postulate that the iridium was scattered worldwide when a comet or asteroid struck somewhere on Earth and then vaporized. A 110-mile-wide (180-kilometer-wide) crater carved out of Mexico's Yucatán Peninsula, called Chicxulub, has since been found and dated to 65 million years ago. Many scientists believe the fallout from the impact killed the dinosaurs.

But Earth's core is also rich in iridium, and the core is the source of magma that some scientists say spewed out in vast, floodlike flows that piled up more than 1.5 miles (2.4 kilometers) thick over 1 million square miles (2.6 million square kilometers) of India. This bout of volcanism has also been dated to about 65 million years ago and would have spread the iridium around the world, along with sunlight-blocking dust and soot and greenhouse gases.

Both hypotheses have merit. Some scientists think both may have contributed to the extinction, and others suggest the real cause was a more gradual shift in climate and changing sea levels. Regardless of what caused the extinction, it marked the end of Tyrannosaurus rex's reign of terror and opened the door for mammals to rapidly diversify and evolve into newly opened niches.

http://science.nationalgeographic.com/science/prehistoric-world/dinosaur-extinction/

Wednesday, 3 February 2016

Atlantis

Does New Theory Pinpoint Lost City of Atlantis?

An author’s obsessive quest leads to a site off the coast of Morocco.

By Simon Worrall, National Geographic

PUBLISHED MARCH 18, 2015

One theory, based on Plato, is that Atlantis was a bit south of Casablanca (above) in

modern Morocco.

Type the word “Atlantis” into Google and 120 million results pop up. Like El Dorado or Shangri-la, the legendary sunken city of Atlantis hovers on the horizon of our imagination, tantalizing, mysterious, unreachable.Meet Me in Atlantis: My Obsessive Quest to Find the Sunken City pulls together the tangled web of conjecture—and sticks a new locator pin in the map.

Talking from his home in Pelham, New York, author Mark Adamsexplains why he thinks Atlantis may have been off the coast of Morocco; how an Irishman created the world’s largest database of Atlantis lore; and how the parting of the Red Sea, in the biblical story in Exodus, may be connected to Atlantis.

You’re best known as a travel writer who has covered real places like Machu Picchu. Why did you choose to write a book about a subject usually discussed in the same breath as UFOs and Bigfoot?

[Laughs] I was writing the Machu Picchu book, and I read this headline in the New York Times: “German discovers Atlantis in Africa.” I was like, what? The fact that someone could actually search for Atlantis and be taken seriously was weird.

A year or two after that, I was working on a magazine story about the greatest philosophers of all time, so I started reading about Plato. And the one thing that came up again and again was that Plato is our sole reputable source for the story of Atlantis.

Your interest in Atlantis began with a series of movies you saw as a boy in the 1970s. Take us back in time.

You can tell from Machu Picchu that I have an interest in lost cities. [Laughs] I think a certain personality loves that type of thing. The germ for me was a series of movies that came out in the late 1970s. They were these super-cheapo pseudo-documentaries, like Beyond and Back or In Search of Noah’s Ark. There was also this show called In Search Of...hosted by Leonard Nimoy. If you get two people in a room and one finds out the other one loves In Search Of... as well, they’ll end up having this Vulcan mind-meld, and talking about it for the next three hours. [Laughs]

It was Plato’s “Critias” that set people off thinking that Atlantis actually existed.

Mark Adams | Author

When is Atlantis first mentioned in the historical record?

The only mention of Atlantis by name is in Plato’s Dialogues (written around 360 B.C.): “Timaeus,” which was a very complicated attempt to explain the universe, and “Critias,” which has dozens of precise details about what Atlantis looked like, and where it may have been located in relation to other landmarks in the ancient world. It was “Critias,” in particular, that set people off thinking that Atlantis actually existed.

I am taken with the theory of Atlantis being in Morocco. Tell us why it could be right—or wrong.

One of the things I’ve found with people reading this book is that different people find themselves sympathizing with different theories. I have four main theories, and I talk to the people behind the theories and visit the locations.

In the case of Morocco, a German computer expert, Michael Hübner, became obsessed with “Timaeus” and “Critias” because he’s mathematically inclined. He set up what’s called a Hierarchical Constraint Satisfaction and looked at every one of Plato’s clues in “Timaeus” and “Critias.” He weighted them and came up with an area on the map that was within 3,000 miles (4,828 kilometers) of Athens, Greece.

What a lot of people forget is that the story of Atlantis is actually a war story where Athens defeats Atlantis. Hübner plugged in the clues—essentially it was like a game of Battleship, [in which] whatever area had the most pegs sinks the battleship, or in this case discovers Atlantis. He theorizes that Atlantis was a little bit south of Casablanca in modern Morocco.

One of the best clues that Plato gives about Atlantis is that there was a series of concentric circles around the city, black and red stone, and of course it was a seafaring society.

Michael Hübner and I walked across the desert and, sure enough, there was black and red striped stone. Then he took me to the edge of the Sahara desert, and walked me up the hillside. Lo and behold, there were these concentric circles on the edge of the desert, and just a few miles away was the Atlantic Ocean. He makes a really compelling case that Atlantis was located in Morocco, and that’s a relatively new theory. Not a lot of people have come up with his hypothesis.

What are the other three front-runner locations?

The traditional front-runner and the only one so far that has gotten a lot of traction with mainstream academics is the island of Santorini in the Aegean Sea. There is real archaeological evidence there. The island has a bull’s-eye shape with a ring around its center, and it has a relatively new volcano, which we know erupted in ancient times.

Santorini was also the site of an important maritime city called Akrotiri, which was discovered in 1967. There is a lot of evidence that it was a flourishing naval center. There were frescoes showing ships, very similar to the details that Plato gives about the Atlantis story. In the mid-1970s, Santorini was major news. Jacques Cousteau went to Santorini to look for Atlantis. It was taken pretty seriously.

The other two are Tartessus, in southern Spain, another lost city from antiquity, which is not too far from the modern-day city of Seville. Finally, there is Malta. Malta has the most ancient temples in the Mediterranean area, and Malta’s culture was destroyed by a tsunami and earthquake.

Jose Maria Galan, a naturalist, says the real story of archaeology and Atlantis is that “no matter how big and powerful you get, you can disappear like that.” Explain.

Jose Maria Galan worked at Doñana National Park [on the southern coast of Spain]. He took me out to the shore there and said: “In the summer, you’ll see thousands of people lying out on the beach. Now imagine that there’s a wave 60 meters high coming in, and you can see how a civilization could get wiped out right away.”

Then he took me out to this area of dunes and we started digging into the hills, and Jose starts plucking out all these various pieces of pottery: Roman pieces, Muslim pieces from the Middle Ages, Greek, all the way back to Phoenician. It was amazing that so many cultures in this quiet spot had come and gone over the millennia. He says: “The only thing we know for sure is that everything gets wiped out in the end.”

I think that is one of the main messages Plato was trying to get across: Time is cyclical, and even a very powerful, technically advanced civilization like Atlantis is going to get wiped out eventually.

You use the term “geo-mythology.” Are there any reliable maps that show Atlantis?

No, though there have been people who have tried to place it on maps. There was a sort of odd, brilliant polymath named Athanasius Kircher, a Jesuit who lived in Germany in the 17th century. He did what’s probably the most famous map of Atlantis, where he placed it in the Atlantic Ocean. But there’s no way of knowing whether he based this on any reliable information or whether he just made it up. The oldest maps we have don’t go back much past 1500. They’re post Christopher Columbus.

Your search for Atlantis took you all over the world, even to Ireland. Tell us about Tony O’Connell and how he started Atlantipedia.

Tony is one of those wonderful people that I got to meet. He and his longtime partner, Paul Evans, moved to the country outside of Dublin to take care of Tony’s ailing mother. Being a very intelligent busybody, Tony was looking for something to fill his time and started getting into serious Atlantis research. He realized there was no single compendium to look for information about Atlantis, so he started this thing called Atlantipedia online. There are thousands of entries—everything you could ever want to know about Atlantis is there! [Laughs]

He was crucial for my research because when I talked to archaeologists, historians, or philosophy professors, a lot of them didn’t want to talk about Atlantis. The subject is like kryptonite for serious academics. You’re not allowed to take it seriously. So I went to Tony, hat in hand, and asked if he could help me out. He said, “Come to Ireland and spend a week, and we’ll talk about it.” Basically, he played Socrates to my Plato. He talked me through all the possibilities; and at the end of the week, I had my four candidates.

I was intrigued by the explanation of the biblical story of the parting of the Red Sea being a tsunami and the Santorini explosion theory—can you tell us more about that?

A lot of the information from Exodus lines up with things that might have happened during the volcanic eruption: the ten plagues, the sky darkening, the sea turning to blood, locusts. If you compare what happens during a volcanic blast, you can see how the effect of a volcanic blast would get translated into the ten plagues that hit Egypt.

One of the more interesting points he makes is that what is commonly known as the Red Sea parting may have actually been the Sea of Reeds, which is a lagoon in northern Egypt. When a tsunami occurs, as we know from what happened in Thailand, the sea recedes. It can go out a half mile or so. This may be what happened when the Jews reached safety on the other side. Then the water came crashing back and wiped out the Egyptians in pursuit.

It would be an incredible coincidence if all these things happen to fall into place. But in ancient history things are often described as happening in a short period of time that may actually have transpired over hundreds of years. So we don’t really know.

Socrates said, “Everything I had done hinged on the truth or falsity of a statement about truth or falsity.” Explain.

Before Plato started writing about Atlantis, he mentions some of the things that are going on in The Republic. But Socrates says: There are stories that we use to teach children. Some of these stories are true; some of these stories are not true. And then there are stories that have some truth and some falsity. The falsity is put in for teaching purposes.

The problem with Atlantis is that we have to figure out whether it’s all true or all false. Plato wrestled with the idea of what’s true and what’s not true. The question is: Does Atlantis actually exist or does it fall somewhere in between? Part true. Part false.

So, Mark, will we meet in Atlantis one day? Or is it all a lot of hooey?

If somebody found concentric circles and an ancient Egyptian inscription mentioning a story like Plato says he found about Atlantis—and those two things are by no means impossible—I think we’d have a pretty good case that there’s a lot of truth in the story. And nobody would be happier than me if we did. I would be over the moon.