A bulldozer gouges into the dirt of a dusty Mexican construction site. But as the machine makes light work of the plot, a curious object is spotted deep underground. There, jutting out from the upturned earth, is a fearsomely large bone. And it’s not on its own down there. Archeologists flood the site and carefully unearth dozens more bones. Hundreds, in fact. And these aren’t your typical animal skeletons. No, these are the remains of a horde of gargantuan beasts, and they’re a once-in-lifetime find.
Yes, archaeologists were thrilled by the rare discovery. But the site’s subterranean secrets didn’t please everybody involved. The Mexican authorities had hoped to construct a brand new airport on the plot by 2022, you see, improving transport links to the hustle and bustle of Mexico City. Perhaps unsurprisingly, the discovery of countless curious relics in the area hampered the build’s progress.
Archaeological work is a slow process, after all, and excavation of the airport site took archaeologists a total of 11 months to complete. The plot’s gruesome secret was first spotted in the winter of 2019. Experts then went on to carefully exhume hundreds of vast, mysterious skeletons from that unlikely location.
But what were these strange creatures which once thrived in the prehistoric landscape? And why did so many of these mythical beasts meet their fate on the outskirts of Mexico City? Well, the answers to these questions provide a fascinating glimpse into what life was like in North America during the Ice Age.
Mexico City was apparently founded by the Aztecs in 1325, and the surrounding area is steeped in history. So it’s hardly surprising that archeologists at Santa Lucía airport have uncovered secrets from long ago. Yet these latest discoveries date back to long before advanced civilizations appeared in this part of the world.
Thousands of years ago, the land where Mexico City now stands looked very different to how it does today. In place of the skyscrapers and parks that make up the modern metropolis were a network of vast lakes – stretching out across the Valley of Mexico. Chief among these was the huge Lake Texcoco, which covered more than 2,000 square miles at its peak.
Eventually, the Aztecs would choose an island in Texcoco as the setting for Tenochtitlan – the settlement that would later become Mexico City. But for a long time, the region was home to a far wilder way of life. And these early humans likely shared the land with an array of spectacular beasts as they eked out a living on the lake’s shores.
This was the time of the megafauna, according to experts. Yes, huge creatures that weighed in at more than 100 pounds could be seen roaming the landscape during this period. And in North America, these often took the form of oversized ancestors of the animals that we know and love today. So, could one of these ancient giants have left behind the bones that eventually turned up beneath Santa Lucía airport?
Might the skeletons have belonged to the ancient horses that emerged on the North American continent some 50 million years ago? Apparently, these creatures disappeared from the region in around the 12th century B.C. Though it’s worth noting that they survived in other parts of the world. Or perhaps the remains were those of something altogether more bizarre – like the glyptodon?
The glyptodon is a giant version of the modern armadillo, and it once thrived in Mexico. Capable of growing up to 11 feet in length, its size was definitely comparable with the vast bones discovered by archeologists at Santa Lucía airport. Over the years, its remains have been uncovered across North America. So could this be the latest in a long line of finds?
Amazingly, these creatures are far from the only candidates for the giant bones discovered near Mexico City. They could have belonged to a dire wolf, which was a prehistoric North American carnivore that lived during the Late Pleistocene and Early Holocene eras. Or maybe they were its competitor: the saber-toothed cat?
It’s also possible that the warmer climate of what is now Mexico City tempted creatures like the megalonyx – or ground sloth – back down south after their forays further north. In fact, fossils belonging to this giant creature have been recovered from modern-day Mexico. Perhaps the skeletons at Santa Lucía airport were left behind by this lumbering beast?
But none of these guesses explain the mass of giant bones that were uncovered during the airport dig. So what were the mysterious creatures? Thanks to earlier excavations, archeologists already had some clues as to what they might find – ones that early humans had inadvertently left behind.
In recent years, evidence has emerged which suggests that humans may have been present in the Valley of Mexico up to 12,000 years ago. This means that they likely interacted with a number of the megafauna species that once inhabited the region. In fact, hunting is believed to have played a significant role in the decline of these giant creatures.
Interestingly, it wasn’t just their relationship with man that sealed the fate of these colossal beasts. The humans adapted as temperatures began to rise. But creatures such as the ground sloth and the saber-toothed cat did not. And one by one, the continent’s megafauna succumbed to extinction – leaving nothing but their great bones behind.
Many thousands of years later – in 2019 – archeologists began excavating the ground where the new Santa Lucía facility was to be built. Originally an Air Force base, the project was announced by the President of Mexico in April of that year. Before that, the authorities had planned to build a new airport to the northeast of Mexico City, but a referendum had stalled work on that project.
A new site was instead chosen some 40 miles north of Mexico’s capital city, and work began on expanding the base into a commercial airport. But as construction got underway, archeologists from the National Institute of Anthropology and History were keen to be involved. Excavations at a site a short distance away had apparently revealed something startling. As a result, experts had hoped that the story might continue.
In November 2019 a team of Mexican researchers announced the results of their latest project. They had made an interesting discovery outside the town of Tultepec, which is some 12 miles from the Santa Lucía airport site. The experts uncovered a pair of artificial pits which had been dug by humans thousands of years ago. Inside, evidence was found that suggested the structures had once been part of a hunting technique – and a successful one at that.
Amazingly, the researchers found no fewer than 14 skeletons inside the Tultepec pits – each belonging to the species known as the Columbian mammoth. The experts theorized that early humans had constructed the six-foot-deep traps so that the huge creatures could not escape. In fact, primitive hunters may even have actively chased the animals towards their fate.
But what did the hunters do with these huge mammoths once they’d caught them? Well, it’s believed that they butchered the creatures for their meat and bone. Altogether, it was a far more sophisticated approach than the primitive spear-hunting that many associate with this time. So were these early humans perhaps smarter than they have been given credit for?
Experts from the National Institute of Anthropology and History had been involved in the Santa Lucía airport dig from October 2019 onwards. And thanks to this nearby discovery, they now knew what to look for. But would the ground reveal any more relics from a time when man lived shoulder-to-shoulder with giant beasts?
Fortunately, researchers did not have to wait long to find out the answer. Over a six-month period they had uncovered at least 60 mammoth skeletons and were due to excavate many more. National Institute of Anthropology and History archeologist Pedro Sánchez Nava told AP in May 2020, “There are too many, there are hundreds.”
Nava explained that over the course of six months, the team had been unearthing the giant bones at a rate of around 10 skeletons a month. And at the time, they predicted that this frequency could continue for many weeks to come. But in the end, the Santa Lucía airport dig surpassed expectations.
Then in September 2020 archeologists made another astonishing announcement. They had discovered at least 200 vast skeletons at the site. Not only that, they believed that there were more waiting to be excavated. And with this revelation, Santa Lucía airport shattered the record for the most mammoth bones ever found at a single location.
According to experts, the bones are between 10,000 and 20,000 years old. They also date back to a time when much of the Valley of Mexico was covered in water. Alongside Texcoco, Lake Xaltocan was another of the interconnected bodies of water that covered the basin. And here, animals such as the mammoth found a hospitable home.
But what drew the megafauna to Lake Xaltocan? Well, a rich habitat of reeds and grasses tempted beasts such as mammoths to feast by its shores. Experts believe that the creatures were capable of consuming an astonishing 330 pounds of these nutrients on a daily basis. Speaking to the AP, Nava explained, “It was like paradise for them.”
The lake was clearly a popular spot, and it drew the vast creatures from far and wide. And today, the site apparently contains so many mammoth skeletons that the bulldozers need to be accompanied by observers. As work continues, these spotters are there to ensure that no bones get damaged during the construction of the new airport.
Dubbed “mammoth central” by some archeologists, the site could well provide some vital clues to how these creatures lived and what led to their extinction. But how did so many of them end up dying in the same location? According to researchers, they may have become trapped in the soft soil of the lake shore.
At the moment, though, experts are unsure whether or not humans played a role in this unfortunate fate. The mammoths may have found themselves stuck in the marshy ground after visiting the lake to feed. So did early hunters take advantage of the natural trap that was created by the lake?
“It’s possible [early humans] may have chased [the mammoths] into the mud,” Nava told the AP. “They had a very structured and organized division of labor.” In fact, archeologists have found several tools forged from the creatures’ bones close to the skeletons.
But the tools made of bone aren’t necessarily proof that humans utilized the natural trap of Lake Xaltocan to hunt mammoths. Alternatively, they may have butchered the creatures after they became stuck in the mud and died. Or the tools could have been crafted from the bones of animals killed elsewhere before being brought to the site.
At the time of writing, experts are carrying out tests on the skeletons to see if they show any signs of human interference. And until this can be determined, they can only speculate about the relationship between mammoths and the early inhabitants of Lake Xaltocan. That said, the bones have still proved invaluable to scientists studying these ancient creatures.
Today, experts believe that the species known as the Columbian mammoth first appeared in North America around one million years ago. The creature’s ancestor – the steppe mammoth – had arrived in the region from Asia several millennia before. And for thousands of years, these giant beasts roamed the Valley of Mexico and feasted on the local vegetation.
According to scientists, these mammoths were capable of growing up to 14 feet in size – around the same height as an adult female giraffe. And while similar species in Europe evolved thick, hairy coats to insulate them from the cold, their North American counterparts did not. Business Insider also notes that they likely had a lifespan similar to that of a modern human: between 70 and 80 years.
We’re all familiar with the popular image of humans hunting mammoths. But the species likely only coexisted for a short period of time towards the end of the creature’s existence. And the Paleoamericans had disappeared just a few millennia after arriving in North America. So was man responsible for their extinction? Or was something else at play?
Now, scientists hope that this discovery might help to uncover the truth behind the mammoth’s decline. Speaking to AP in September 2020, paleontologist Joaquin Arroyo Cabrales explained, “What caused these animals’ extinction, everywhere there is a debate, whether it was climate change or the presence of humans. I think in the end the decision will be that there was a synergy effect between climate change and human presence.”
It is rare to find such a large grouping of mammoth skeletons together in one place, according to scientists. Paleontologist Ashley Leger told AP in September 2020, “A very specific set of conditions that allow for a collection of remains in an area but also be preserved as fossils must be met. There needs to be a means for them to be buried rapidly and experience low oxygen levels.”
Mammoth graveyards such as this one are rare, but humans have been uncovering their giant bones for hundreds of years. In fact, even the Aztecs – who ruled from nearby Tenochtitlan – once stumbled across vast skeletons buried beneath the ground. Yet they could only guess at the creatures that had left them behind. According to Nava, the people were so stumped that they concluded giant humans had once walked the Earth.
Interestingly, the Santa Lucía airport excavations may also reveal more about the role that mammoths played in the early human diet. Speaking to the AP in May 2020, Nava explained, “They used to think it was very chance – sporadic. In fact, it may have been part of their daily diet.”
But it wasn’t just mammoths discovered at the site in Mexico. No, researchers also uncovered other remains – including five horses and camels. And according to those on site, there are still several excavations due to take place. So will Mexico City’s new airport have any more tricks up its sleeve? The facility is apparently on track to open in 2022, so archeologists may be up against the clock.