The BIG Questions About Ancient Civilizations | Unveiled XL

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The BIG Questions About Ancient Civilizations</h4>

It may feel as though today is really important but actually, in the grand scheme of the timeline of the Earth, what happens now is but a tiny, tiny fragment of a footnote in the infinite records of this planet. There is so much history stretching out before we got here. And, really, there’s only a small portion of it that we properly understand. There are gaps that need filling, then… and plenty of claims, theories, legends, myths and apparent pieces of incontestable evidence to do exactly that.

This is Unveiled, and today we’re taking a closer look at the BIGGEST questions surrounding ancient civilizations on Earth

When we think of ancient civilizations, we might picture Egypt as something of a starting point for all to follow. The Egyptians were so successful and ingenious that it can seem like they kinda wrote the rulebook when it comes to organizing humans into a functioning society. But is that really how it was?

Was there a civilization before Ancient Egypt? 

Ancient Egypt is not only one of the oldest civilizations in the world, it’s also one of the most impressive. There are many - usually smaller - organized groups across history, but ultimately Egyptian culture has proven to be so rich and awe-inspiring that it’s created for itself an entirely separate branch of academic study, called Egyptology. There’s just so much to learn about the era and the people.

That’s not to say that we know all they knew, however. Many of the building techniques used in Ancient Egypt, for example, including for the iconic pyramids, remain something of a mystery - as we found out in a previous video! Although, there’s some argument that this mystery may have been intentional, as the Egyptians seemingly left nothing by way of a clear record describing how they achieved many of their most spectacular feats. Which means that today, thousands of years later, we’re still scratching our heads over some of it.

Ancient Egypt first developed as a civilization around the year 3100 BCE, and it stood as one the world’s leading examples of social cohesion for some thirty centuries after that. For more than three thousand years. However, despite Egypt’s general image as an inspiration for all civilization, it’s not usually held to be the first recorded, advanced society that humanity ever created. Broadly, historians and anthropologists list a couple of key features required for a given group to upgrade to the status of civilization. They need to be (to some degree) settled, they need advanced social features (like a government, perhaps), and they need developing technology of some kind - with a system of writing often held to be especially important. 

In short, then, there were other civilizations around at the same time and even before Ancient Egypt. One was the Indus Valley Civilization, which formed in Asia, around 3300 BCE, a couple hundred years before the rise of Egypt. And, while there can be some disagreement over precisely when various civilizations established themselves, there’s research to suggest that Indus Valley could be thousands of years older than even that… putting it potentially even further back in time. 

It existed across a massive area stretching from modern day Afghanistan, to Pakistan, and India, making it notably larger than most other ancient empires, including Egypt’s. In its prime, Indus Valley had at least one thousand towns and cities, which were home to more than five million people. It’s credited with developing, amongst other things, early water and drainage systems, brick houses, an ever-crucial writing system, and a standardization of weights and measures to ensure that society ran smoothly. As the Egyptians also did with the Nile, the people of the Indus Valley owed much of their success to their strategy of building along a major river, the Indus River. 

Even older than the Indus Valley, however, is Mesopotamia - a sprawling civilization made up of multiple major groups, including the Sumerians and Akkadians. Mesopotamia arose on fertile land in the Middle East, across modern day countries including Iraq, Kuwait, Turkey, and Syria, sometime around 3500 BCE. As well as being potentially the oldest ever civilization, ancient Mesopotamia also developed what’s generally thought of as the first ever writing system - by using clay blocks for dedicated record keeping. In addition to its apparent invention of writing, Mesopotamia is also credited with inventing the wheel, the first maps, and the first boats, as well as the first ever means by which to measure time.

The Indus Valley and Mesopotamia civilizations are both thought to have emerged a few hundred years earlier than the ancient Egyptians, then, but were there any confirmed groups before even them that we’ve yet to discover? We certainly know of smaller groups that formed in earlier periods, such as the Jiahu settlement in China, which has been tentatively dated back to the year 7000 BCE… although the numbers of people involved there only reached into the hundreds, rather than the multi-millions as seen in Egypt. 

There are other structures and stories that more severely (or more famously) call the mainstream narrative of human civilization into question, too. The legend of Atlantis is perhaps the most well-known example of a tale of a bygone age. If it were true, then the Atlanteans will’ve existed sometime around ten to twelve thousand years ago - around the year 10,000 BCE. But, of course, the Atlantis story is still widely held to be more allegory than a true record of past events. And, in fact, some explanations for the story’s origins trace it back to a myth told in Egypt, which eventually found its way to the ears of the Greek philosopher and chief Atlantis purveyor, Plato. 

In terms of physical evidence for a later civilization, however, the mysterious megalith site, Göbekli Tepe, lays down perhaps the strongest challenge to Egypt and Mesopotamia regarding age. Göbekli Tepe is a massive archeological site in modern day Turkey, and it’s home to the oldest known stone megaliths in existence, thought to date back as far as the year 9500 BCE. We’re now thousands of years before even the beginnings of Ancient Egypt, then. The megaliths feature carved images, too, seeming to show things like clothed people, animals roaming the land, and perhaps even religious practices of the time. Researchers are still debating whether Göbekli Tepe can yet be classified as evidence of another whole civilization, though. So much about it remains unknown, and only a small percentage of the site has been excavated. Stone tools have been found, and possible workshops close to the megaliths, but this could still have been just one small and isolated community, rather than one part of a wider civilization. If Göbekli Tepe is ever confirmed to have been part of something bigger, though, that something could emerge as the new “oldest civilization in history”.

We haven’t yet mentioned the far more unconventional theories, out there, however. One such theory - or one such thought experiment, at least - comes from space scientists Gavin Schmidt and Adam Frank. They created the Silurian Hypothesis in an effort to stoke the debate on whether other, non-human civilizations could’ve developed on Earth before ours did. The general thinking is that if the Earth is around 4.5 billion years old, which it is, and human civilizations of any kind have only been around for just a few thousand years of that time… well, in the grand scheme of things, we’ve barely made an imprint. The Silurian Hypothesis non-committedly asks us, then, to imagine a civilization that might’ve hypothetically lived not thousands of years ago, but hundreds of millions of years ago. 

In all likelihood, we would never be able to uncover any evidence of such a group today, in the here and now… with Earth’s tectonic and geological activity burying and recycling it over time. The Silurian Hypothesis leads us to wonder, then; how can we be sure about a past that might’ve been lost to us? It’s a line of thought that’s also inspired ideas like the infamous Younger Dryas Impact Hypothesis, which proposes that a comet struck Earth some 12,800 years ago - supposedly wiping out an advanced civilization at the time, and serving as something of a reset button for life on Earth. The theory isn’t widely supported by conventional scientists or historians, though.

What’s clear is that our picture of the past, while it’s thought of as reasonably reliable, is subject to change. History can’t be rewritten, of course, but our understanding of it can be reshaped. And so, it could yet be that we’re missing something truly substantial. Consider our current understanding of the dinosaurs. It’s improving all the time, but it remains patchy at best. And that’s despite the fact that the dinosaurs - these giant creatures - roamed the Earth only sixty-six million years ago (a blink of an eye compared to the full age of our planet). They were also on Earth for some 165 million years before they died (which is far, far longer than humans have been here for, so far). But we’re still so limited on what we can learn, even about the dinosaurs.

Dissecting the route we’ve taken toward contemporary society and civilisation is, then, an extremely tricky task. Perhaps it’s no wonder that so many eye-catching theories have been thrown into the mix. But, even if we stay within the realms of just the most widely supported science, history, and archeology, we know that Ancient Egypt was never out on its own. Certainly, it’s one of the oldest civilizations we know about, and a forerunner for so much of human progress, but there were others alongside it, and most likely before it. And, research pending, there could yet be even older groups, too. 

The world is constantly changing. Societies rise and fall, empires crumble and monuments get abandoned. Throughout history, humanity has gradually gained knowledge… but we’ve forgotten a lot of what came before us, as well. Many of the most famous and beautiful ruins from the ancient world weren’t just lost to time, though… so, what happened to them?

Why did these ancient civilizations mysteriously collapse?

First, it’s important to distinguish between a culture and a civilization. While the civilizations and cities themselves have been lost, the people who inhabited them – and their cultures – often still exist today. For example, probably the most famous collapsed civilization of all time, the Maya, still has a population in the millions in Mexico and Central America. The mystery, then, isn’t where did the people go, but why did they go? What convinced ancient citizens of lost civilizations that they’d be better off leaving their own advanced and beautiful cities rather than remaining within their walls?

The classic Maya collapse wasn’t the only Maya collapse in history – there was another in the 2nd century AD – but the one that’s been confounding archaeologists for years, now, happened between the 8th and 9th centuries. Enormous Maya cities characterized by distinct, terraced pyramids like Copán (in modern day Honduras) and Tikal (in Guatemala) were abandoned before the year 1,000. Archaeologists can be confident of the dates because the Maya wrote the date onto the monuments they built, and such records disappear around the 9th century, when it seems monument construction stopped, and cities fell into disrepair. 

It’s generally accepted that at this time the Maya travelled further north to different Maya centres, like Chichen Itza in what’s now Mexico, but there are dozens of theories on exactly why they left the southern lowlands to begin with. Some of the most popular explanations suggest that the more southerly regions were, around the time the Mayans moved, rendered uninhabitable by logging and a severe drought – a “megadrought” by some estimations. Essentially, the Mayans had cut down too many trees, so when the drought rolled in, topsoil was eroded, and their once-reliable cities were no longer able to feed their growing population. So, under threat of starvation, the Mayan people dispersed and found new places to live. Another theory, though, is that it was an endemic disease, potentially a widespread parasitic infection, which primarily destabilized the Maya and forced them to relocate. Then, another suggests that regional conflicts might’ve been to blame. Today, while we know they did move, we’re still not certain on their reasons for doing so.

But the Maya weren’t the first or last civilization to collapse in the Americas. Much earlier were the Olmecs, Mesoamerica’s earliest recorded, advanced civilization who thrived around 1,500 BC. The Olmecs were known for building statues of enormous heads, now called “Olmec colossal heads”, many of which survive today. Their largest city was San Lorenzo (also now in Mexico), which collapsed as far back as 900 BC, nearly 2,000 years before the end of the Maya. It’s theorized that the Olmecs had to move because of volcanic activity; that a big enough eruption could have decimated their crops, forcing them to go elsewhere for food. 

Much further north is the United States’ “First City”, Cahokia, a Native American city that at its height had a population between 10,000 and 20,000 in the 11th century AD - which is roughly equivalent to the population of London, England, in the same period. Early European settlers purportedly didn’t believe that Native Americans could be capable of building such a city, and so wrongly attributed it to another group, like the Phoenicians (from present-day Lebanon), or even the Vikings, instead. Today, the ruins of Cahokia are found in the Midwest, close to St Louis, Missouri. The site bears evidence of at least two major floods in its past, prompting many to suggest that it was the flooding which forced the population to disperse. While they can’t rival Cahokia for size or scope, there are many older Native American sites across the continent, too… with some of the oldest belonging to the Ancestral Puebloans who lived in the American southwest. Some of their remarkable dwellings (carved into cliff-faces) survive today, such as the Cliff Palace in Mesa Verde National Park, Colorado.

Far away from the Americas, civilizations in Europe and Mesopotamia had risen and fallen as well. The oldest advanced civilization in Europe was the Ancient Minoans, who lived on the island of Crete between the years 3,000 and 1,000 BC. Unsurprisingly, Minoan ruins (like the Palace of Knossos) are now major historical sites in modern Greece, but details on what happened to the Minoans remain elusive. The leading theory blames their demise on the Thera Eruption, occurring on a nearby island now known as Santorini, which is thought to have been one of the biggest volcanic eruptions in human history. It happened around 1,600 BC, creating a tsunami that decimated Minoan settlements. It’s believed by some that the fate of the Ancient Minoans is actually what inspired Plato’s world-famous Atlantis allegory, depicting a powerful civilization destroyed by the gods. Interestingly, the Minoan Civilization also has ties to another mainstream Greek myth, that of Theseus and the Minotaur; some believe that Knossos itself is the real-world location of the legendary labyrinth.

But what about the oldest recorded civilization we know of? Well, it also collapsed, for various reasons. Ancient Mesopotamia was the birthplace of the written word more than 3,000 years BC. Some of the oldest texts in the world are written in Sumerian, with Sumer (today Iraq) being where the civilization emerged from. Mesopotamia hosted a number of civilizations (including the Sumerians and Akkadians) across an exceptionally wide region for thousands of years, lasting until the fall of Babylon in the 6th century BC, before it was ultimately conquered by Alexander the Great two centuries later. 

Another civilization thriving around the same time, though, was that of the Indus Valley, the remains of which can be found in Pakistan. It’s also called the Harappan Civilization after one of its largest cities, Harappa. In their prime, cities like Harappa and Mohenjo-Daro were extraordinary; boasting the world’s oldest sanitation systems, public baths, evidence of city planning, and potentially even of elected officials, they were significantly ahead of their time. But archaeological evidence suggests that Indus Valley success was short-lived, and that by 1,900 BC, the cities were in chaos. Dead animals and people lay unburied in the streets, disease was rife, conflicts were common, and eventually, the centres of the Indus Valley civilization were abandoned. Again, there are multiple theories as to why it all fell apart. Some believe the changing course of the Indus River was chiefly to blame… for others it’s a string of severe earthquakes and weak monsoons, leading to social instability and water shortages. Ultimately, many of the Indus Valley people moved southeast into parts of modern India where their influence can now be seen in various other ancient sites.

There is one theory, however, which proposes a grander connection between the end of the Indus Valley civilization and the end of Mesopotamia, and also with the demise of the Old Kingdom of Ancient Egypt, and the long lost Liangzhu culture in Ancient China, for example: the 4.2 Kiloyear Event. Speculated to have occurred around 2,200 BC, the 4.2 Kiloyear Event is said to have been a worldwide epidemic of severe droughts that crippled many powerful societies. It didn’t spell instant doom for all of them, with some surviving from this point longer than others, but it’s suggested that it did spark the beginning of the end for most. However, many scientists don’t agree with this idea, arguing that no one single event can be blamed for the collapse of multiple societies across a considerable timespan. Nevertheless, all indicators are that severe droughts were a major reason that many of the world’s most powerful civilizations fell… and if not droughts, then other weather events and natural disasters. Connected or not, similarities can be drawn.

That said, sometimes human and political reasons are to blame, when empires get too big to be properly and effectively managed. Once the largest empire in the world, for example, the Mongol Empire, splintered in the 13thcentury AD into four separate empires with different rulers. This move meant the Mongol Empire could eventually be taken over and dissolved by the Ming Dynasty to the east and the Russians to the north. And sometimes wars really do bring down vast, seemingly impenetrable empires, too; with one of the leading causes for the fall of Rome in the 5thcentury AD being that the Romans suffered too many consecutive military defeats. There’s less by way of “mystery” in these cases, because the outcomes are more linked to human choice and activity, but we have seen civilizations effectively dismantled in this way, too. 

In every case, there are myriad, complex reasons behind people abandoning their cities and starting afresh elsewhere, and societal collapses don’t happen overnight. Often, the decline and desertion of a civilization takes hundreds of years, as it did with the Maya, the Harappans and the Romans in particular. But natural disasters like flooding at Cahokia or the eruption of Thera can accelerate the process.

While the iconic terms of “UFO” and “Unidentified Flying Object” date back only as far as the early 1950s, some level of human interaction with some form of inexplicable airborne vehicle seemingly dates back not just centuries, but thousands of years. There’s no doubt that modern humans have an interest, perhaps obsession, with finding UFOs… but these things also captivated ancient civilizations, too. And, while many of the oldest recorded sightings have since been attributed to various meteorological or astronomical phenomena, there are still some events that have made their way into the annals of history and continue to elude explanation even today.

We’ll start with what’s often referred to as one of the first recorded mentions of a potential UFO sighting - although its validity is firmly up for debate. The details are allegedly found in the Tulli Papyrus, a document that it’s claimed dates back to the Egyptian Empire. According to a translation of the Papyrus by one Boris de Rachewiltz, an Italian-Russian Egyptologist, an unusual event unfolded during the reign of Pharaoh Thutmose III, which was between 1,479 and 1,425 BCE, almost 3,500 years ago. 

It’s said that a "circle of fire" descended from the sky and that its “mouth had a foul odour” although it didn’t have a head. This bizarre object was described as about fifteen feet across, and after several days was purportedly joined by more just like it. An apparent fleet of unexplained entities, appearing as though out of nowhere and stretching across the sky… until one evening, the objects rose in unison and moved south over the horizon, never to be seen again. The Pharaoh supposedly then ordered these strange events to be recorded immediately, and the story eventually made its way onto the Tulli Papyrus, where it apparently waited for more than three millennia until it was finally unearthed.

Importantly, the authenticity of the papyrus itself remains very questionable, and so the UFO claim it reveals is met by many with scepticism, too. The translation is actually of a secondary record of the papyrus itself, and the original source has long been lost. But, nevertheless, the story has triggered ongoing discussion within the UFO community. While, in some ways, the description of the initial object in particular does perhaps appear reminiscent of a passing comet, it’s also thought that the Ancient Egyptians were very knowledgeable when it comes to astronomy - and so, perhaps, they wouldn’t have confused a comet for something else. What’s more, that incongruous, extraordinary detail that the object’s mouth had a foul odour (despite it not having a head) is speculated by some to be the result of an ancient culture attempting to describe emission fumes - something they, of course, wouldn’t recognise, but an advanced alien race may well have produced out of their extraterrestrial, alien spaceships.

While the Tulli Papyrus has yet to be officially validated, however, today’s second ancient UFO sighting comes from a far more reputable source. Titus Livius, more commonly known as Livy, is considered one of the leading historians of ancient times. And, while his histories do involve some mythological influences, his greatest work, "The History of Rome", is considered one of the primary sources for understanding ancient Roman culture. In his work, Livy covers the great civilization's story, from its legendary founding around 753 BCE… all the way up to the year 9 BCE. And, while it’s also true that Livy's work features some anomalies, nothing is quite so peculiar as his recounting of the events of the Second Punic War. It was a crucial, seventeen-year conflict, but what it’s perhaps best remembered for is Livy’s various descriptions of phantom ships that appeared during it, in the skies above the battle.

The first instance allegedly occurred in the first year of the war, in 218 BCE, when Livy wrote that phantom ships had been seen gleaming in the sky over Rome. Then he continued with an event the following year, describing that round shields were again seen in the sky - this time over the ancient city of Arpi. Livy finally records yet another UFO sighting, decades after the war in 173 BCE, as a great fleet in the sky close to another ancient city, Lanuvium. 

But what exactly were these objects? Many have recognized the seeming similarities between Livy's shield-shaped somethings and our modern, archetypal depictions of a flying saucer. And, while Livy himself lived some 150 years after the events that he describes, his position as a trusted historian means that his records are generally regarded as accurate. There’s certainly scepticism when it comes to the phantom ships, but so much of the rest of Livy’s work is thought to be reliable… based, as it was, upon records from the Annales maximi, a thoroughly fact-checked and verified archive, set up during the Roman Republic.

For today’s third ancient sighting, though, we switch to the work of the noted Greek-turned-Roman historian, Plutarch, and to another, separate event, this time shortly before a planned battle was set to take place. According to Plutarch, in 74 BCE, the army of the Roman Empire was marching on the army of the King of Pontus, Mithridates VI, in the region of Phrygia, which is in modern-day Turkey. However, the two armies never met. Just as tensions were about to peak, a large body of flame is said to have descended from the sky between the two sides. Taking it as an omen from the gods, the two armies are then said to have separated, saving them from a bloody conflict. 

According to Plutarch, writing about an event which was allegedly witnessed by thousands more people, the fiery object was shaped like a jug of wine and was of a molten silver colour. Again, there are numerous contemporary claims that this incident may have simply been caused by a falling meteorite, but not everyone agrees. The NASA scientist Richard Stothers, for example, reasoned why it may not have been a meteorite, as part of a 2007 study into UFOs from classical antiquity. For Stothers, that molten silver colour (while not wholly out of place) doesn’t quite match with what scientists would expect to see during a meteorite event. But, also, we should again more seriously take into account the astronomical knowledge of those present during the sighting. As with the Egyptians and the Tulli Papyrus, it’s thought the Ancient Romans had an advanced understanding of astronomical phenomena… shaped by a long history of recording meteorite impacts. If this was a meteorite, then, they perhaps would have known and understood it. But, according to Plutarch, they didn’t… so the jug-shaped fireball may have been something else.

Perhaps the foremost reason to doubt Plutarch’s account surrounds the historian’s personal reputation. While known for his general reliability, he’s also noted for often emphasizing the moral lessons of history, and perhaps at the expense of accuracy. One theory, then, is that Plutarch’s recordings of this unusual event were intentionally allegorical, to relay a warning message about war, and not designed to be taken literally. But still, the fact that this phenomenon was reportedly witnessed by thousands of soldiers means that it remains one of the most intriguing ancient UFO sightings out there.

Finally, to another celebrated historian, setting the scene for yet another war in history, and describing another unexplained event in the sky. Like Livy and Plutarch, Titus Flavius Josephus is another prominent historian of the ancient world. Working in the first century AD, he primarily covered Jewish history, and the Jewish-Roman wars. But, while he was again praised for his accuracy, he seemingly couldn’t make sense of everything… and famously wrote of an apparently inexplicable, airborne event within his vast work, “The Wars of the Jews or History of the Destruction of Jerusalem". 

According to Josephus’ account, near the beginning of the First Jewish-Roman War, in 66 A.D., groups of apparent soldiers and what appeared to be charging chariots were witnessed running in the clouds above the setting sun. There was allegedly, then, an entire (but incomprehensible) scene playing out in front of many baffled onlookers, watching the skies. An apocalyptic vision, perhaps. Referring to his own role in recording the event, Josephus himself foretold that what he had written may well go on to be understood as only myth or fable, but he insisted that this was no made-up story. Initially, then, the phenomenon was deemed by some to be a sign from God… but, in more recent times, there’s suggestion that Josephus' work may actually be a recording of an early sighting of an alien UFO. The soldiers were perhaps the aliens, the chariots were perhaps the spaceships. As with all the potential UFO events mentioned today, however, there is of course plenty of scepticism, and no-one can claim to know for sure.

But, what’s your verdict? All four of these events are isolated incidents, occurring across various major civilizations, at different locations and at different points in history. Were they natural space or weather phenomena? Allegorical fabrications? Or could the commonalities and peculiarities of these events really be the result of age-old, extraterrestrial visitations? 

The idea that advanced extra-terrestrials have at one time visited Earth, or that they continue to visit Earth, has long been a popular line for alien enthusiasts. State-sponsored initiatives ranging from Project Blue Book in the 1950s and ‘60s, to the Advanced Aerospace Threat Identification Program in the twenty-first century, have now clocked up thousands of UFO and alien reports. The idea, though, is almost always that these unconfirmed, otherworldly creatures could be invading our planet… but what if the opposite was actually true?

Did Ancient Civilizations Move Away From Earth? 

For decades, there has been serious speculation - some credible, some not so credible - that humans may not have been the first intelligent life to evolve on our planet. Earth is more than 4.5 billion years old, and while we can chart various structural and sociological changes with a surprising degree of accuracy (particularly by analysing layers of rock), the suggestion that Earth might’ve hosted other advanced species billions of years before human beings has never truly gone away. It’s a favourite theme for science fiction writers, too, with “Doctor Who” being one of the first fictional works to feature it, with the introduction of the Silurians in 1970 - a race of humanoid beings with advanced intelligence which, crucially, predate man. 

But is it really possible that creatures as intelligent or more intelligent than humans could have existed on Earth before us, before fleeing the planet for some reason? One way to investigate evidence of previous civilizations is to consider their energy usage. Generally speaking, advanced beings need more energy as their population grows, and arguably one of the simplest ways to get that energy (that we know of) is to burn fossil fuels. When we use fossil fuels, we’re releasing carbon dioxide back out into the atmosphere, and scientists have various techniques to measure how much CO2 was or wasn’t present at any particular period in history. We can, therefore, chart carbon “spikes” in history, and debate what caused them.

In recent times, it’s thought that, as a result of human activity, our carbon levels have risen faster than ever before… so, were a future civilization ever to look back to now, there’d be compelling evidence that intelligent life did exist in our time period. The Silurian Hypothesis prompts us to ask whether we’ve seen something similar before, though, such as at the beginning of the Eocene Epoch about fifty-five million years ago. At that time, it appears as though a period of abrupt global warming also occurred - today called the Paleocene-Eocene Thermal Maximum - which, perhaps, would have created similar conditions to what we’re experiencing, or are on the verge of experiencing, today. It’s by no means proof that an advanced race existed at that time, more an indicator that something - natural or otherwise - was causing the Earth to change.

In the hypothetical event that ancient, unknown civilizations did once live here, however, a spike in global warming might well have been reason enough for them to leave. We only need to look at humanity’s various plans and efforts to spread out into the solar system right now, to imagine the thinking behind such a move. In the twenty-first century, we’re eyeing up Mars in particular, but also other nearby planets and their moons - including Jupiter’s Europa and Saturn’s Titan. For some ancient society living on an earlier Earth and in an earlier solar system, though, the destination of choice might’ve been different as well. 

Some other (often fairly far-fetched) proposals in favour of pre-human civilizations also include that they may have been advanced enough to cover their tracks; that, in their latter stages, they deliberately chose to remove all traces of themselves, perhaps even anticipating that another civilization would develop on Earth after them. Either that or, in an earlier effort to tame their own climate change, they successfully developed carbon negative technologies - the like of which we’re trying to build today - thereby erasing their historical imprint, before switching planets just because they could. Importantly, though, while those motivations might seem valid enough, there’s still nothing by way of direct evidence that such a forward-thinking society actually did ever exist. 

For now, all we really have to go on is that we can say with confidence that Earth has undergone climate change before, but we’re not certain what prompted past global warming spikes. We’re increasingly sure that today’s climate change is accelerated by humans, but that doesn’t automatically mean that previous temperature rises must have also been triggered by advanced civilizations. For now, that’s a leap for science fiction more than science fact.

In the meantime, though, it’s not as though humans should expect to be remembered forever. Yes, humanity’s impact on Earth has been considerable - we’ve built skyscrapers to the clouds and spaceships to get us to the moon - but it could all be quite temporary in the grand scheme of history. For Adam Frank, the chances are that after a couple million years; “any physical reminder of our civilization [will have] vanished”. Long term, direct evidence of our existence seemingly lies in the cities we’ve built, the roads we’ve laid, and the monuments we’ve constructed… but, were humans to for whatever reason disappear, then they’d all quickly start to crumble, before the vines, weeds, rivers and oceans gradually reclaim and eventually disintegrate them. When you consider, too, that despite it seeming as though we’ve conquered much of the Earth, only about one percent of the planet’s surface is actually considered to be urbanized... it might not even take that long! Regardless of any desire we might have to leave a legacy, Earth could be quickly wiped clean of humanity’s accomplishments… leaving it primed for another, far-future intelligent species to emerge, and to analyse rock samples wondering whether anything came before them.

Perhaps then, the same thing really did happen to some other advanced species; they forged a life on Earth, ran into problems, and either died off without a trace or relocated beyond our reach - their achievements now reduced to just a few layers of rock or ice, waiting for today’s scientists to truly decipher their meaning. In this way, it’s a hypothetical reality which conveys a real-world warning… that the Earth might not always be so hospitable to us. 

But, in truth, it is still a hypothetical reality first and foremost. We cannot say with any certainty that an advanced civilization was here before us, or that they became advanced enough to move away. 

So what’s your verdict? How do you view the ancient past? In this video, we’ve covered pre-Egyptian societies, potentially pre-human groups, alleged UFOs from long-lost periods of history, the real world reasons why past civilizations have collapsed, and an incredible theory that ancient life might even have moved away from Earth before we even got here. The really exciting thing, though? There’s still so much more to learn and discover!