Post

How to get URL link on X (Twitter) App

On the Twitter thread, click on or icon on the bottom
Click again on or Share Via icon
Click on Copy Link to Tweet
Paste it above and click "Unroll Thread"!
More info at Twitter Help

Fall of Civilizations

Sep 1, 2019 • 10 tweets • 5 min read • Read on X

Today, we know that Sahara Desert as a vast sea of sand and salt flats. But up until around 5,000 years ago, this is how it looked.

It was a green landscape of Savannahs, lakes and rivers where early humans lived, hunted and fished.

(📷 flickr.com/photos/cchurch…)

This era is known as the African Humid Period, and it peaked between 9,000 and 6,000 years ago.

In those days, the landscape of the Sahara would have supported rolling grasslands, lakes and rivers, as well as sparse forests of trees like acacia.

It was also home to Neolithic human communities.

In fact, rock paintings have been found in the central Sahara that depict abundant animal life, and even people swimming, in places that are today a barren desert.

(📷 Dr. Stefan Kröpelin, Köln University)

These communities were largely hunter-gatherers, but were increasingly beginning to practise pastoralism, ie. keeping cows and sheep.

They observed the world around them, and created incredible artworks like the so-called Dobous Giraffes (pictured).

But the days of their societies were numbered.

Changes in the earth's orbit known as its orbital precession, a change in tilt that cycles every 25,000 years, forced the African monsoon rains southward, and the Sahara became drier.

Trees and large plants would have died first, until only grass remained. And then even the grass would have withered and died.

Without roots to hold together the earth, the topsoil blew away, and desertification set in.

While estimates vary wildly, some believe that this process could have taken only a few hundred years.

Human societies fled the advance of the desert, moving to the coasts. Their populations concentrated there, and they built settled societies that lived in cities.

The Green Sahara reminds us of the dramatic changes that can arise from even gradual planetary shifts.

It reminds us that history is a record of change, and that things we often take for granted are not as certain as we might think.

I talk more about the Green Sahara and its legacy in the latest episode of Fall of Civilizations.

Find it here, or on any major podcasting platform:

Spotify: open.spotify.com/episode/7EXVuI…
YouTube:

Stitcher: stitcher.com/s?eid=63547032…

Thanks for listening!

If you like my work and want to support the podcast, you can also contribute here. patreon.com/fallofciviliza…

• • •

Missing some Tweet in this thread? You can try to force a refresh

This Thread may be Removed Anytime!

Twitter may remove this content at anytime! Save it as PDF for later use!

More from @Fall_of_Civ_Pod

Fall of Civilizations

@Fall_of_Civ_Pod

Jan 12, 2021

It's often said that the indigenous people of South America never developed a system of writing.

But this isn't entirely true. In fact, they created a unique and complex system of notation based on the tying of knots, known as quipu, which remain undeciphered to this day.

The quipu were usually made from string, spun from cotton fibers, or the fleece of camelid animals like the alpaca and llama.

The cords stored information with knots tied in vast assemblages of string, sometimes containing thousands of threads.

In some analysed quipu, the combinations of thread length, colour, knot type and knot position allow for up to 95 possible combinations, which could represent numbers, symbols or even sounds.

Read 25 tweets

Fall of Civilizations

@Fall_of_Civ_Pod

Feb 29, 2020

One of the most remarkable journeys to take place in the ancient world was that of the Chinese explorer Gan Ying.

In the first century, he became the first recorded human to travel the whole length of the route known as the Silk Road, and wrote a remarkable account of his trip.

For the Han dynasty of ancient China, the first century was a time of unprecedented contact with the rest of the world.

They had succeeded in re-conquering a fractious desert region to the West known as the Tarim basin, a sandy depression in the heart of the Tibetan Plateau.

The Tarim basin is home to the Taklamakan Desert, the second largest shifting sands desert in the world.

This desert is the only route to the West in the north of China, and so for millennia trade caravans of Bactrian camels have passed through the oasis cities of this region.

Read 22 tweets

Fall of Civilizations

@Fall_of_Civ_Pod

Dec 16, 2019

A thread on some of the most amazing examples of art in the Aztec codices.

These were illustrated books written by the indigenous people of Mexico both before and after contact with Europeans, and contain incredible glimpses into their lives, their memories, and their beliefs.

The Aztec codices were books written on deer skin or bark paper. The Aztecs had vast libraries, but after the Spanish conquest of the city of Tenochtitlan in 1521, all of these libraries were destroyed.

Only 16 pre-contact codices have survived.

Folio 65r of the Codex Mendoza, an Aztec codex from c.1541.

This page shows how an Aztec warrior and an Aztec priest could rise through the ranks of their orders. The rank of a warrior depended on how many enemies he had captured during war.

Read 24 tweets

Fall of Civilizations

@Fall_of_Civ_Pod

Feb 17, 2019

In 1982, a Turkish sponge diver Mehmed Mehmed Çakir was diving for sponges off the coast of Uluburun in southwestern Turkey.

He was about 44m deep when he came across a strange clutter of objects, half-buried in the silt & sand.

He knew that he had discovered something ancient, and he quickly alerted archaeologists.

But he couldn't have guessed just how ancient these artefacts were, or how important they would prove to be.

Further investigation revealed that Çakir had discovered an ancient shipwreck, dating back to the Bronze Age.

Archaeologists put the date of its construction around the year 1,300 BC, making it over 3,300 years old.

Read 16 tweets