72 Million Year Old Dinosaur Bonanza Found in Mexico

72 million years ago, the desert of Coahuila looked very different. For a start, it wasn't a desert. This was the late Cretaceous period when, to the north, a vast, inland sea covered most of the south and western states of the present day USA. Coahuila sat at the southern plains of this sea. It was a huge, swampy estuary, covered in lush vegetation. It was here that the dinosaurs came to drink and feed; and some left traces that are only now coming to light.


Tyrannosaurus Rex
This was the hunting ground of Tyrannosaurus Rex, but that infamous species of dinosaur certainly wasn't alone out there. The remains of Coahuilaceratops Magnacuerna, a dinosaur named after the state, were discovered last year here. That was just the beginning, for it seems that this area is a treasure trove of pre-historic remains, on a par to those in Wyoming or Utah. Moreover, paleontologists have only just begun to scratch the surface.

Earlier this week, it was revealed that 207 dinosaur footprints have been found so far in Coahuila. These lay alongside fragments of vertebrae and long bones, belonging to a selection of creatures, who died there 72 million years ago. They are so recently uncovered, that they haven't yet been fully identified and classified. However, they are likely to include the Hadrosauridae, Ornitomimidae and Tyrannosaurus families.


Hadrosauridae


Ornitomimidae
The discoveries have been made over three sites, covering 5,000 sq. meters (53,750 sq. feet, in Coahuila. The largest was within the city of General Cepeda. Paleontologists have sealed off an area of Las Aguilas, which is where the footprints were found. It will eventually be open to the public, once the experts have done their jobs.

INAH-Coahuila Center paleontologist Felisa Aguilar explained, "Those places are still hidden under vegetation and won’t be opened to the public until they are registered so that their future conservation can be guaranteed."

Other remains, in the same area, have been dated to the Pleistocene, which makes them a mere 2.5 million years to 10,000 years old.

Earliest American Found in Quintana Roo

Mexico often has the air of an archaelogists' adventure paradise about it. I defy anyone to visit Cobá, without feeling like they are on the set of an Indiana Jones film. But beyond the vacationers, the experts are flooding in too. So many of Mexico's treasures lie undiscovered beneath the surface of the soil. This past week has seen not one, but two highly significant finds. One of these might change what we know about the history of the Americas. Has the first trace of humanity, on this continent, just been found in Quintana Roo?


In a previously unknown cavern, 4,000ft (1,200 meters) below the surface of the Yucatán Peninsula, diving explorers found the remains of dinosaurs, alongside a human skull. They have yet to be officially dated, but the presense of many megafauna bones, including that of a mastodon, suggests that they date from the Pleistocene Period. In short, they could be over 12,000 years old.


These Mastodons once roamed the Americas.
The remains were discovered in the depths of the labyrinthine Aktun-Hu system. These are a series of subterranean caves and tunnels, beneath Quintana Roo, which were flooded during the last Ice Age. Quintana Roo (famous for being the state where Cancún is) lies upon limestone, through which groundwater easily seeps to create this vast underground world. However, caves like this one, where the discoveries were made, weren't always so far down. The human being inside could well have simply walked in there, before it was ever flooded.

If this human is as ancient as the explorers believe, then (s)he may pre-date even La Mujer de las Palmas (the Lady of the Palms). It certainly adds credence to the theory that the earliest human settlers, on the Americas, came from Europe. They would have sailed from modern-day France, following a wall of icebergs, lining the Atlantic. Until recently, the most common belief was that humans reached the Americas from the north, crossing the Bering Strait, between modern-day Russia and Alaska.


La Mujer de las Palmas - does the latest find pre-date her?
The team, who made these discoveries, had to trapse through dense jungle, carrying their heavy equipment, before even making the deep dive. More details can be read at National Geographic: Skull in Underwater Cave May Be Earliest Trace of First Americans.

Also in the spotlight this week are reports of the discovery of a 3,000 year old Olmec sculpture, in Ojo de Agua, in the state of Chiapas. Standing at 3ft (0.9 meters) tall, it is made of carved, volcanic rock. It depicts a figure, with his hand held up to the Heavens, though no-one knows precisely who he is. The best guesses are Corn God, Tribal Chief, Tribal God or Priest.


Olmec Sculpture found in Chiapas
It was a chance discovery, uncovered by locals, in 2009. Fortunately there was an archaelogist in the area, who was able to quickly reach the site and document precisely how and where it lay. John Hodgson, an anthropology doctorial candidate at the University of Wisconsin-Madison, USA, immediately sealed off the area, into a 250 hectare archaeological zone. This allowed experts to thoroughly chronicle the site.

The intervening years have shown that Ojo de Agua was once a thriving Olmec settlement. Raised platforms and formal pyramids can be discerned around central plazas. It was abandoned around 2,000 years ago.

New Species of Dinosaurs Found in Mexico

For amateur and professional dinosaur-hunters alike, Mexico is the new frontier of exploration.   For centuries, paleontologists have combed areas in America and Canada looking for dinosaurs; but few people have been doing the same south of the border.   Now that they have begun, they are uncovering prehistoric treasures, set to revolutionize our understanding of the world so long ago.

In May 2010, it was announced that three new species of dinosaurs had been discovered.   Their fossilized remains were found in the Mexican state of Coahuila, by a team working under the auspices of the University of Utah.   The most exciting of these, Coahuilaceratops magnacuerna, was named after the state.   It has the longest horns of any dinosaur ever uncovered.


Artists impression courtesy of the University of Utah

Coahuilaceratops magnacuerna (pron. Koh-WHE-lah-SARA-tops mag-NAH-KWER-na) is a relative of its more famous cousin, Triceratops.   The name breaks down as Coahuila (Mexican state, where it was found); ceratops (Greek word meaning 'horned face'); magna (Latin for big/great); and cuerna (Spanish word for horn).  So it's the great horned, horn-face from Coahuila.   Once you realise that the horns stretched out 4ft (1.2 meters), you can understand the emphasis on said appendages.

This dinosaur lived around 72 million years ago.   It was about the size of a modern-day rhinoceros, but it weighed 4-5 tonnes.   Though it could certainly hold its own in a fight, Coahuilaceratops magnacuerna was a vegetarian.   His fossilized remains were found near to the village of Porvenir de Jalpa, near Saltillo, by a team which included Mexican, American and Canadian paleontologists.   The specimens have been deposited in a permanent exhibition, at the Museo del Desierto (Museum of the Desert), in Saltillo. The skull of the Coahuilaceratops magnacuerna will be revealed to the public, at the same museum, later in the year.

For those wishing to gain the fine detail, then a book was published last month which covers these findings. 'New Perspectives on Horned Dinosaurs' by Michael Ryan (Indiana University Press) announced the unearthing of Coahuilaceratops magnacuerna.

Paleontology is so under-developed in Mexico that Coahuilaceratops magnacuerna is only the fourth Mexican dinosaur ever named.   It wasn't discovered alone.  There were also the remains of a duck-billed creature, which has yet to be properly classified.   There were also members of the tyrannosaurus family, though not the infamous rex, as well as smaller relatives of the velociraptor.   The team also identified a dinosaur trackway, with many species of both carnivores and herbivores criss-crossing it, then leaving their remains for modern hunters to find.


In the Late Cretaceous Period (97 million to 65 million years ago), the world looked very different.   Central America had yet to form.   This made Mexico the southernmost tip of the Northern Americas.   In addition to this, high water levels had made a sea of the central, low-lying areas of the USA, Mexico and Canada.   The whole continent was split, with eastern and western landmasses huddling around this warm, shallow sea.   The western side was fairly narrow.  Dinosaurs lived and died on a peninsula sandwiched between the sea and the rising mountains to the west.   This peninsula has been named Laramidia; and it is the prospect of learning about this area that has scientists so excited.

"We know very little about the dinosaurs of Mexico, and this find increases immeasurably our knowledge of the dinosaurs living in Mexico during the Late Cretaceous," said Mark Loewen, a paleontologist with the Utah Museum of Natural History.  "Rather than focusing only on individual varieties of dinosaurs, we are attempting to reveal what life was like in Mexico 72 million years ago, and understand how the unique ecosystem of Mexico relates to ecosystems to the north at the time."

His colleague, Scott Sampson, added, "As the southernmost dinosaurs on Laramidia, we are confident that Mexican dinosaurs will be a critical element in unraveling the ancient mystery of this island continent."

If you are interested in dinosaurs, then Mexico is certainly the place to be watching in coming years.   For those wishing to make their name in paleontology, then heading to our beautiful country with a trowel and some brushes could well be the way forward.   Good luck!

Chicxulub: The Extinction of the Dinosaurs

It has been commonly accepted for decades that, 65 million years ago, an asteroid hit the Earth and wiped out the dinosaurs.  This catastrophic event changed the course of evolution on this planet and, ultimately, allowed human beings to grow and flourish.   What is, perhaps, lesser known is where this asteroid landed.   This was the smoking gun that would prove the theory, but scientists and explorers scoured the Earth for years before it was finally found.

In March 2010, 41 international scientists met, in the USA, to evaluate the evidence.    The location had been strongly suspected since the 1970s, but this was the moment when all research had been completed and all conclusions picked over for validity.    They were finally able to proclaim the site with absolute certainty.  The deadly asteroid hit the Yucatán Peninsula, in Mexico, around the area where the village of  Chicxulub (pron. Chick-shoo-loob) now sits.  The March 2010 report may be read on-line here.

The Chicxulub crater is 112 miles (180km) wide.  There is evidence of impact down to 2000–3600 ft (600-1110 meters).  The asteroid that caused it must have been 6 miles (10km) in diameter.   Here's how that might have looked:



The impact of the asteroid would have detonated with the force of  4×10²³ joules of energy.  That's 2 million times more powerful that the greatest of mankind's bombs.  Mega-tsunamis would have risen all over the Earth, some thousands of feet high.   The sky would have rained down with burning boulders, each causing their own atomic bomb style explosions, as they landed.   This would have been happening halfway across the globe, thus was the force that they were being thrown through the sky.   Meanwhile, the shockwaves through the Earth itself would have triggered volcanic eruptions and massive earthquakes.   All of this would have taken mere seconds to occur. 

For the creatures not killed in this sudden violence, then the next six months would have been deadly.   Soot and debris filled the skies, blocking out the sun and destroying vegetation.   The rock deep within the impact site contained a lot of carbonate and sulfate, which vaporized in the air to create a global rain of sulphuric acid.   This burnt the skin to the bone on contact.  Without food and with air and water laden with poison, 50% of the world's species of flora and fauna simply became extinct. 



After it was all over, the world looked like a very different place.   The huge predators, like Tyrannosaurus Rex, were dead.   The survivors tended to be those small enough to hide from the rain and to be able to live on small amounts of food.   It would also be very helpful to be warm-blooded, to counteract the global fall in temperature.    Those who made it through the apocalypse included the insects and the mammals.   In short, this was humanity's big chance to develop and, finally, take over the world. 

It is a musing of historians and scientists to imagine the 'what if' scenario of this asteroid never hitting the Earth.  For sure, the huge dinosaurs would have continued on for millions more years and may still be with us.  The number of mammals would have been kept down because of them.   Even  paleontologists cannot say with certainty whether human beings would have eventually evolved.   But even if we had, then it's difficult to imagine that the Earth would now be covered in our cities, technology and landmarks, when there were Tyrannosaurus Rexs trampling them all down again.

Of course, it's been 65 million years since the aesteroid hit the Yucatán Peninsula.   The crater has slowly been practically hidden by the land and sea on top of it.   It's clearly viewed from space, but from the ground, the best we have to see are a ring of cenotes marking out the crater's trough.   Nevertheless, Chicxulub is still worth visiting.  It retains its fishing port charm, while its beautiful beaches, chilled out atmosphere and delicious cuisine mark it as a favourite vacation spot for Mexicans.   For those who wish to see the environmental signature of the crater, then there are tours available within the village.