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[♩INTRO]
When most people think of archaeology,
they imagine Indiana Jones-type digging in holes,
looking for objects made by ancient communities.
And that’s partly true.
But there’s another field where the archaeologists
are the ones making the objects.
It’s called experimental archaeology.
Experimental archaeologists make hypotheses about how people in the past
crafted various artifacts or performed incredible feats.
Then, researchers test those hypotheses by attempting to recreate the methods.
This can involve anything from reconstructing Polynesian boats to brewing
the beer Egyptian pharaohs drank.
And by replicating these processes,
researchers gain an understanding of how advanced ancient people were.
They can actually feel what it was like to live in the past.
And they can even learn how to improve our lives today
by resurrecting long-forgotten technologies.
Some of the most common things experimental archaeologists
recreate are stone tools.
And surprisingly, replicating these objects doesn’t just reveal things about our
ancestors’ handiwork, but also tells us about their cognition and language.
In 2010, experimental archaeologist Lyn Wadley
explored ancient people’s cognition by replicating hafted spears.
Hafted weapons are made by attaching a stone blade
to a wooden shaft using a sticky substance.
And they seem pretty simple, until you make them from scratch.
Wadley performed chemical analyses to determine the exact materials
people in Africa used to craft hafted weapons around 70,000 years ago.
Then, she had a go at it herself and published the results
in the journal Current Anthropology.
After collecting the materials, she used a rock to carve other rocks into blades.
This is called flint-knapping, or just knapping.
And yes, using a stone to chip a rough rock into a tool as sharp as a scalpel
is exactly as hard as it sounds.
In her test, Wadley used one of the blades to whittle a stick into a shaft.
Next, she crushed rocks to make ochre, which is a pigment made from rocks
rich in iron oxide, the same compound that makes rust, rust-colored.
Then, she mixed the ochre with beeswax and sap from an acacia tree
and cooked it in a fire to make glue.
By the time she finished crafting the spears,
Wadley concluded that humans from that time were capable
of complex cognition, which involves mental flexibility, abstract thinking,
planning abilities, and more.
Specifically, she proposed that people had to engage in abstract thinking
to imagine how to invent a multi-ingredient adhesive.
They also needed to be mentally flexible, because each batch of glue
has to be prepared differently depending on,
like, the stickiness of the sap that particular day.
And people were using planning because they needed to wait
up to six days for the glue to set.
Plus, they must have developed advanced language
to teach each other the skills.
And she isn’t the only researcher who’s proposed this.
In fact, many scientists suspect language showed up in the first place because
our ancestors needed to school each other in the art of stone toolmaking.
But it’s difficult to prove that because talking, you know, doesn’t fossilize.
So, in 2017, experimental archaeologists taught stone-knapping to newbies
to determine how much communication was necessary to learn the craft.
They chose a type of knapping that was invented around two million years ago.
One group of newbies tried to learn by observing expert flint-knappers
and imitating them, with no language involved.
And the results... were kind of terrible.
Another group of beginners was taught with gestures.
And they did pretty well.
But a third group was taught with spoken communication.
At first, they did as well as the gestural group.
But in the second phase of the experiment, only the speech group
was able to remember the method and perform it on their own.
This suggests that this kind communication is the best way to help people
retain the information they’ve learned.
And while the researchers didn’t look at this specifically, that’s likely true of
signed languages as well, since they convey the same amount of information.
Either way, the researchers concluded that language may well have emerged
to teach people to skillfully bang rocks together.
Now, stone tools were some of the first things
experimental archaeologists recreated, starting in the 1800s.
But experimental archaeology didn’t really come into its own until the mid-1900s.
And one of the things that launched it was a boat.
In 1947, a Norwegian anthropologist named Thor Heyerdahl
set out to prove a controversial hypothesis.
He proposed that the Polynesian Islands in the South Pacific
were settled by South Americans who drifted some 8000 kilometers
across the ocean in wooden rafts.
And to prove this was totally possible, he and five other people went to Peru
and built the Kon-Tiki, a 13-meter-long balsa wood raft
based on explorers’ records of ancient South American boats.
Then they set off, and 101 days later,
successfully crashed into a reef on the Tuamotu Islands in Polynesia.
Except… it turned out Heyerdahl’s hypothesis was wrong.
In 2003, scientists used DNA studies to show that South Americans
didn’t actually settle Polynesia.
But the Kon-Tiki was still hugely significant, in that it helped scientists reimagine
what was possible to study with experimental archaeology.
And it paved the way for a more successful experiment:
the 1976 voyage of the Hōkūleʻa, a replicated Polynesian canoe.
This time, it wasn’t just a boat being recreated:
It was a nearly forgotten navigation technique.
At the time, the scientific community was debating how people settled
the Polynesian Triangle starting around 800 BCE.
The Polynesian Triangle comprises more than 1000 islands sprinkled around
25 million square kilometers of ocean between Hawai’i, New Zealand,
and Rapa Nui, or Easter Island.
Many scientists argued that Polynesians accidentally
found the various islands by drifting with the wind.
Others gave the Polynesians more credit and believed they deliberately
discovered islands using finely-tuned navigation techniques.
To settle the issue, archaeologists, anthropologists,
and historians designed a Polynesian voyaging canoe.
They based it on canoe drawings from the 1700s
and their best guess about what earlier canoes looked like.
Next, they found a master navigator from Micronesia named Mau Piailug
one of the few people left in the world who was well-versed
in ancient Polynesian wayfinding.
Piailug and crew set off from Hawai’i in the canoe,
navigating by the sun, the stars, the clouds;
the flight patterns of land-based birds;
and the feel of the ocean swells, which change direction
as they bounce off distant lands and blow with the winds.
After 34 days, they arrived in Tahiti just as planned
a journey of more than 4000 kilometers.
And by succeeding, they demonstrated that ancient Polynesians did have the
sophisticated skills required to explore and populate thousands of islands.
And that’s one of the things about experimental archaeology:
It inspires a lot of respect for our ancestors’ knowledge and expertise.
That’s certainly the case when it comes to historic people’s culinary talents, too.
Because yes, experimental archaeologists also bake bread,
brew beer, and cook medieval meals.
Recreating long-forgotten food and drink allows researchers to experience the
same tastes, smells, and other sensations that ancient people experienced.
It can tell researchers about ancient people’s diet,
health, culture, and knowledge of culinary science.
Plus, it’s tasty.
Like, in 2019, an archaeologist, a physicist,
and a microbiologist resurrected 4000-year-old Egyptian yeast.
And they’re using it to bake bread and brew beer
the way it was done in the time of the pharaohs.
Which is incredible for so many reasons.
First: Yes, yeast can survive in a hibernation-like state for thousands of years.
And if you feed it the kind of grain that it ate thousands of years ago,
in this case, emmer wheat, it will wake up and be like,
“Hey, let’s make some bread.”
Knowing this, the scientists got access to Egyptian artifacts in a museum.
Then, they took a specially-designed syringe and suctioned up yeast
from beer vessels, bread pots, and a bread loaf that had been buried
under a pharaoh’s tomb.
Next, they began a series of experiments.
They brewed one beer using yeast from a beer vessel,
and another beer using yeast from the bread,
because one question they’re trying to answer is how much
ancient Egyptians knew about the science of yeast.
If the bread yeast and the beer yeast are the same species of fungi,
it might mean the Egyptians were scraping the frothy yeast
off of their beer and kneading it into their dough.
And that would suggest they knew that the same mysterious something
was making their bread rise and their beer ferment.
Which doesn’t sound like a big deal to us now, but would have been huge.
Our current understanding of history is that scientists didn’t know exactly
what yeast was and what it did for beer and alcohol until the mid-1800s.
At the time we’re filming in 2021,
it looks like the Egyptians actually didn’t know that, because the two beers
tasted very different.
But the upcoming DNA tests will tell us for sure.
In the meantime, these scientists are trying to fill in the gaps
of the archaeological record, because inconveniently,
ancient Egyptians didn’t leave behind recipes.
So the scientists are studying chemical analyses of baked goods,
plus drawings of bakers on a tomb wall.
And they’re conducting baking experiments to figure out how ancient Egyptians
nurtured their sourdough and baked it in clay pots buried
underground with a bunch of coals.
Besides just being a good time, this is also important to learn because
bread and beer were central to ancient Egyptian culture.
In fact, the people who built the pyramids were paid in bread and beer.
So, baking and tasting 4000-year-old bread gives us a feel
for what it was like to be a pyramid builder — without all the heavy lifting.
Now as you’ve probably noticed,
experimental archaeology can be an immersive experience!
And some experiences are more immersive than others.
Like, when you build a Neolithic farm and start living on it.
A lot of experimental archaeology takes place at archaeological museums,
or open-air museums.
These are places that have replicated farms, houses, forts,
or other structures from the past.
And the public can visit to learn about life in various time periods.
But these museums can also be sites for scientific research,
like at Lejre Historical-Archaeological Experimental Center in Denmark.
This place is famous for an extreme experiment.
Around the world, there are archaeological sites where houses or villages have
burnt down, maybe because of a cooking accident or pyromaniac marauders.
And these sites can be difficult to analyze.
So in 1967, archaeologists at Lejre filled a replica Iron Age long-house
with pottery and other objects.
And then they set it on fire.
25 years later, other archaeologists excavated the site.
Crucially, they were not told what the original house looked like or what was in it.
The researchers then compared their analysis of the charred remains
to the original house to help archaeologists better interpret scorched sites.
Overall, the researchers were really accurate.
But they were shocked that the 25-year-old burned house
had deteriorated so much it resembled a legit Iron Age house
from more than 2000 years ago.
They concluded that some other archaeological sites
might actually be burned dwellings that have decayed beyond recognition!
In other experiments, archaeologists are trying to replicate super-strong
Roman concrete and Bronze Age insulation to learn how modern people
can build more sustainable structures.
Construction contractors from Austria are even looking
at archaeological experiments to improve building materials.
Because really, experimental archaeology is part science, part adventure,
and part exploration, but it’s not just about the past.
It can also help us understand some great skills and ideas from years gone by
that might help us live better lives today.
And it’s efforts like these that are celebrated in the album Music for Scientists,
a tribute to science and the people who make it happen.
It was inspired by the beauty of science
and of making our world, and our past, more knowable.
The album is also an homage to the people of science.
If you think you’d enjoy listening to Music for Scientists,
check out the link in the description to get started.
[♩OUTRO]