Prehistoric timeline in Africa pushed back by more than 10M years | Hacker News Reader

Prehistoric timeline in Africa pushed back by more than 10M years

phys.org

157 pointsPaulHoule94 comments

I always like to keep a context for this sort of stuff. Here's my growing list:

  giant impact that formed the moon (4.5bya)
  great oxidation event (2.4-2.0bya)
  multicellular life (1.5bya-600mya)
  trilobytes appear (521mya)
  landplants (470mya)
  first land animal (428mya)
  pangea forms (335mya)
  pangea breaks apart (200mya)
  angiosperms (275mya)
  trilobytes disappear (252mya)
  ginkgo (200mya)
  flowering plants become abundant (100mya)
  antartica was a rainforest (90mya)
  dinosaurs died (65mya)
  primates (55mya)
  azolla event (49-48mya)
  pantherlike cats (10.8mya)
  first humans (5mya)
  megalodons go extinct (2.6mya)
  modern humans (300k years ago)
  yellowstone's last eruption (70k years ago)
  humans reach turtle island (30-20k years ago)
  african humid period, green sahara (14.5-5k years ago)
  beringia land bridge gets inundated (11k years ago)
  saber tooth tigers go extinct (10k years ago)
  horses go extinct in north america (9k years ago)
  shift to wetter climate makes Amazonia transition from grasslands to jungle (2k years ago)

I wrote a coffee table photobook that includes some of those.

https://impacts.to/downloads/lowres/impacts.pdf

You may find that the bibliography cites slightly different dates:

https://impacts.to/bibliography.pdf

For example, dinosaurs died out around 66.04 ± 0.05 Ma.

I had not read "coffee table photobook" before, nice concept. (and yours is great, btw)

That reminds me of those big table screens that Microsoft (?) was selling years ago. Only seen in Hawai 5-0 again. Are they still for sale? What was the name?

In standard Microsoft fashion, they were also called Surface.

See: https://www.windowscentral.com/microsoft-surface-pixelsense-...

"Surface", it's no longer available and they repurposed the name to use for their tablets.

The timeline becomes wildly condensed in more-modern years. Would love to see a "zoomed in" timeline from 250Ma-0Ma to capture that detail on more pages. :)

Wow, this is beautiful.

This is super cool!

> dinosaurs died out around 66.04 ± 0.05 Ma.

The dinosaurs didn't die out, and are alive in abundance today.

I know what you mean, but it's interesting how many otherwise scientifically accurate publications use the taxonomic term as if though our understanding of the origin of birds hadn't evolved since the 1950s.

The term “dinosaur” is used almost exclusively to refer to non-avian dinosaurs. In scientific literature the qualification is usually made explicit, but I belief even there it is sometimes clear enough from context to avoid the explicit qualification.

Thats technically correct, the worst kind of correct. The same way dinosaurs, and hominids are both lobed-fin fishes (Sarcopterygii) as are all tetrapods.

Similarly, I have a number from the back of the envelope in my back pocket that roughly 2.2 trillion person-years have been lived (by modern humans), roughly one third before agriculture and one third after the industrial revolution.

World War 2 was roughly one percent of history, weighted by person-years.

My favorite framing of that is that in homo sapiens, life has only been proven to have a mortality rate of 93%.

My personal mortality rate is 0% so far. Not sure what the fuss is about.

> World War 2 was roughly one percent of history, weighted by person-years.

Do you mean history since WW2 has been about one percent of history?

The population during the ~decade WWII covered was 2.3 billion, so about 23 billion person-years were lived, about 1% of the total.

You can argue that total down considerably -- other stuff happened during that decade, and while something like 10% of the population fought in the war, it wasn't truly global -- but it's still impressive on the scale of history. The US Revolutionary War was probably only 1/1000th of that.

What interval is the remaining third?

Unless I'm misunderstanding, the remaining third would be between the advent of agriculture and the industrial revolution.

So the first third took millions of years, second third took roughly 6-7k years, and the last third took 200 years?

Like everything on the prehistoric timeline, the dawn of agriculture keeps getting pushed back. I think that's believed to be older than 10k years ago now.

With the caveat that the intensity of the increasingly older agriculture is increasingly low.

There are clearly agricultural societies, where >90% of calories come from cultured plants, and there are clearly hunter-gatherer societies that predate them, where ~0% do. We used to believe in a relatively sharp cutoff between these, where once people learned to grow food, they quickly moved to mostly grow their food. This is no longer thought to be the truth, and there was likely a "transitional period" of many thousands of years as people very slowly hunted and gathered less and planted more.

(Why believe in a sharp transition? Because there is a lot of archeological evidence for it, so it clearly happened in lots of places. It's just that this doesn't represent people inventing agriculture, but it spreading to a new area and displacing older lifestyles, either by migrations of people or of ideas.)

The first is only hundreds of thousands, starting with anatomically modern humans and not all of our precursors who lived for millions of years before that.

Though that may not change much -- depending on your estimates, Neanderthals probably spanned 3-30 billion person-years, as little as 0.1% of modern humans. All human precursors (5-10My worth) might be margin of error on the modern humans' totals.

On the other end of things, if we plateau at around 10 billion humans, it will only take about 75 years to accumulate the next third (well, quarter) of human existence.

You could add Woolly Mammoths going extinct 4k years ago. Notable it its own right, and also because they overlapped with the pyramids being built.

For most intents and purposes, Wooly Mammoths became irrelevant to the ecosystem, and to all but a few human populations ~10,000 years ago. The last surviving mammoths were isolated on a few scattered islands.

Yes. But the general perception is Wooly Mammoths were in another era long before the more "modern" pyramids and such.

TBH I wasn't aware the two overlapped. Now I know :)

Agree! Also Göbekli Tepe overlaps with saber tooth tigers extinction (10kya).

I didn't know that. Good idea!

Some one was trying to revive mammoth ! what happened to that project.

That's a great idea! A big part of why I keep a personal list is because I can include things I really understand and care about (I tend to read more about archeobotany). But I highly encourage anyone to keep their own list. It's fun to watch it grow over time as you add entries that are actually meaningful to you

Good list. I would add the evolution of sexual reproduction, 1.2-2 bya. It seems to be a one-time leap and snowballed into the modern complexity of life.

Also, do flowering plant coincide with insects?

I'd add when any life began:

    single-celled life (3.8-4.3bya)

...which is notably close to when the Solar System formed (4.6bya)

... 4.6bya - a good chunk of how long the universe even existed.

One might assume then that life is inevitable. Seems like too much if a coincidence (although I appreciate the tautology of that thought).

Or that "intelligent" life is very unlikely if you consider that our planet will no longer be inhabitable in roughly the next 10% of its total existence and 7% since it's estimated microbial life appeared.

If human equivalent creatures had taken just 10% longer to appear the sun would have dried up all the water on the earth and wiped its atmosphere before it happened.

It's hard to say for certain that there has never before been an intelligent species. Over hundreds of millions of years even evidence of cities (even assuming that all intelligent species would even make cities) could be entirely wiped away.

especially true if you consider that if there were hundreds of civilisations scattered across the Universe, the average distances across space and time would still be hundreds of times larger than we could deal with right now, or perhaps ever

for a civilisation with advanced rocketry and telescopes similar to what we have right now, it would still be very unlikely to observe us - firstly because we've only been around at all of a tiny fraction of the time the planet exists, and secondly because despite of all the ruckus we are currently causing in the planet, we'd still be very hard to observe from sufficiently far away

I have all sorts of deluded fantasies regarding U-235 found in gabon.

https://www.iaea.org/newscenter/news/meet-oklo-the-earths-tw...

Shout out to the Silurian hypothesis. It’s been linked here many times, so I won’t link to it again.

The satellites of Saturn and Jupiter will still be chugging along.

Our star is unusual, as well over 90% of stars are smaller (and thus longer lived). Though if you go small enough you start dealing with planets in the habitable zone being tidally locked.

But if a species capable of rocketry had not developed, there is no way complex life would be able to get to those satellites.

The increased likelihood of being tidally locked is not the only problem with smaller stars. As a rule, larger stars are more stable and smaller stars are more active. This is made worse by the fact that the habitable zone is closer to the star for smaller stars. Most stars in the universe probably can't support life as we know it because any planet close enough to be warm would get it's atmosphere stripped off by flares.

> But if a species capable of rocketry had not developed, there is no way complex life would be able to get to those satellites.

I'm talking about continuing evolution of the life that may already be there.

Informative points about stars.

The alternative explanation is that seeds from a previous evolution started colonizing the planet as soon as the medium became viable. But that's like cheating.

Panspermia is not cheating. If we believe abiogenesis to be vanshingingly unlikely on any one planet, panspermia paralelises discovery of a solution.

You surely knew I was half joking. Anyway, I'll explain a little further. I said cheating because panspermia, as I understand it, has a very narrow window of usefulness.

If surface abiogenesis is unlikely, panspermia is more unlikely because it needs the former, plus a way for the spores to survive in space, the travel of interplanetary, maybe interstellar distances, atmosphere re-entry and developement in a new environment.

Another factor is that, if we accept the current estimations for the age of Universe and the fact that some elements only are present in second or third generation star systems (because they were formed inside novas), we could be one of the first guests to the party. Panspermia would place abiogenesis even further in the past.

The only scenario in which panspermia would be more likely is that some components that are needed for life can only appear in space and develop on the surface.

That's not to say that panspermia is in itself an absurd idea, actually the fact that some elements need to be created inside stars means that we're somehow children of the stars, it just happens that panspermia isn't a great substitute for abiogenesis. An amplifier, maybe.

Perhaps we understand panspermia differently. I understand it as a possible answer to the question: how did most of the life in the universe arrive where it is presently to be found? Clearly not all life, since as a matter of certainty abiogenesis has occurred at least once.

>> If surface abiogenesis is unlikely, panspermia is more unlikely because it needs the former, plus ...

That depends. Panspermia gets a huge multiplier from distributing the number of planets and eons on which abiogenesis might have happened just once. So it depends on the relative impacts of very different factors - neither of which have been well quantified.

If panspermia had ever been feasible, it was likely more so in the earlier universe. Personally, I prefer it because it seems to follow the Copernican Principle.

So it depends on the relative impacts of very different factors - neither of which have been well quantified.

Well, that's... correct. I still think that it's less probable, but I have no way to prove it :)

... and overlapping the the Late Heavy Bombardement.

https://en.wikipedia.org/wiki/Late_Heavy_Bombardment

Not really. It's 300-800 million years. That's not nothing. It just looks small by comparison to the time elapsed since then.

Recommend two nice books on this: the ancestor's tale by Richard Dawkins and Otherlands by Thomas Halliday. Both absolute page turners!

Very cool!

There was an article a while arguing that we humans are very early in this universe and that’s why we don’t see any other alien species.

There was a list of 7 steps that needed to happen for humans to exists.

I don’t remember them, but I think would be to cross check if all of them are on your list.

Edit: found the theory. It’s called Grabby Aliens and they use a concept called “hard steps” of evolution.

>There was an article a while arguing that we humans are very early in this universe and that’s why we don’t see any other alien species.

I recall that discussion and added to it with a link to a PBS SpaceTime Episode[0] which discusses this in some detail.

Since you find it interesting (I certainly do), check it out. Actually PBS SpaceTime has lots of other really awesome stuff too![1]

[0] https://www.youtube.com/watch?v=uTrFAY3LUNw

[1] I am unaffiliated with PBS SpaceTime, rather I'm just glad it exists!

I try to keep my list focused on entries that are meaningful to me (I have an interest in archeobotany) so I only add things I feel I have a good understanding of. But I highly recommend other people try keeping their own similar lists and watching them grow over time. Really helps out when you come across articles dealing with big timespans

Here's a good one you can add: https://www.wired.com/2010/01/ancient-seafarers/

Somebody got on a boat and ended up in Crete 100k years ago!

(Also you forgot the ice age, heh)

I never knew horses went extinct in North America. Apparently we don't really understand why either. Fascinating.

Horses are from North America, originally.

Crazy timeline.

They're from North America.

They seem to go extinct before local civilizations are able to leverage them, missing out on a huge force multiplier.

Europeans reintroduce them much later and use them successfully to conquer large swaths of land.

The "inferior" Native Americans realize the utility of horses and very quickly they become so skilled at using them that today their archetypal image is that of a horseman.

Native American society was technologically inferior.

They lacked written word and the wheel at a time when Europe (and parts of Asia) had the printing press and extensive engineering and mathematical accomplishment.

The Americas were far behind Eurasia by every metric.

There’s a discussion about this in ecological terms by historian William Cronon in his book "Changes in the Land" (1983), which talks about the ins and outs of this so-called technological inferiority, but also touches upon the superiority (or symbiosis) of the indigenous people living lightly on the land, and having an understanding of sustainability that Europeans are only now coming to acknowledge as useful and important.

https://en.wikipedia.org/wiki/Changes_in_the_Land

Native Americans had writing... many indigenous American cultures, such as the Olmec, Maya, Aztec, Zapotec, and Toltec, developed writing systems. Other native peoples to the north—mainly Algonquians—had organized pictographing, a common precursor of writing.

People of South America were also the first humans ever to practice metallurgy. Indigenous Americans mastered smelting, soldering, annealing, electroplating, sintering, alloying, low-wax casting, and many other metallurgical techniques independent of any Old World influences. They invented metallurgy a full 3,000k+ years before anyone in the old world ever did (~1200BC in Europe)

Also farming. I mean let's face it, Europeans were probably some of the worst farmers to ever rely on farming. Europe was basically going from one famine to another up until the Native Americans gave them the potato. In addition to the potato (which saved millions of European lives) they also gave them: beans, corn, peanuts, quinoa, potatoes, tomatoes, lima beans, cassava, coke, amaranth, sweet potatoes, peppers (in addition to a ton more that are mostly grown locally still)

I think you should at least do some basic reading before making such sweeping and uninformed generalizations about an entire continent

You’re arguing that in one particular area, metallurgy, the Americas were ahead of Europe.

But that’s not what we’re comparing. We’re comparing the technological state of Europe and Asia to the Americas when the Americas were introduced to the world permanently in the 1500s. Not all Native American tribes were farmers. Speaking as the group as a whole is silly except to state that no tribe was nearly as advanced as the powers in Europe and Asia.

This was shared with me recently, graphical version of similar-ish milestones: https://www.livingcarbon.com/deep-time

So. The Amazon was grasslands in Jesus time? Weird

Not completely, but many sections of it were yeah. Some anthropologists have posited that humans played a major role in the transition towards jungle. Botanists know that you can't really explain the distribution of many plant species without the context of human culture. Some ecologists have even gone as far as to label Amazonia a "manufactured landscape" as we realize more and more how heavily the landscape was shaped by the 10+ million pre-Columbian indigenous people that lived there (I mean, this is the place that gave us potatoes, corn, tomatoes, peppers, sweet potatoes, beans, peanuts, etc. These people are plant experts!). At least as 10-12% of terra firme forests are anthropogenic in nature and many of the most common trees/plants are domesticated for human use.

No surprise why indigenous people are at the forefront of environmental defense movements. It's also one of the most dangerous place to be an environmental activist for this reason. 40% of all environmental defender murder victims are indigenous persons and 15% of all such killings happen in the Amazon

The prairies in North America are human shaped as well. The natives knew that fresh grass grew after a wildfire, so they'd start fires regularly to keep the prairie grasses suppressed, over the centuries the amount of prairie grassland vs forest shifted to grow the prairies.

Yeah. That's not too long ago. Also with the current pillaging, I don't think it'll last in our lifetime. You can see the distraction on Google earth by going back 20-30 years.

I asked ChatGPT 4 if it could add any entries. It came up with the following. I haven't checked for veracity, I'm using it more as an interesting exercise/starting point for checking for gaps:

Origin of life (3.5-3.8 bya): First single-celled organisms.

Eukaryotes emerge (1.6-2.1 bya): First eukaryotic cells.

Ediacaran biota (635-541 mya): Soft-bodied multicellular life.

Cambrian explosion (541 mya): Rapid life diversification.

Carboniferous Period (359-299 mya): Winged insects, high oxygen.

Permian-Triassic extinction (252 mya): Largest mass extinction.

Mammals evolve (225 mya): Small, nocturnal mammals.

First birds (160 mya): Birds from dinosaurs.

K-Pg extinction event (66 mya): Dinosaurs extinct, mammals rise.

Grasses evolve (70-55 mya): Emergence of grasses.

Ice Ages (2.6 mya - present): Repeated ice ages.

Agricultural Revolution (12k-10k years ago): Agriculture emerges.

Writing systems (5k-4k years ago): Writing invented.

Industrial Revolution (18th-19th centuries): Rapid industrialization.

Atomic Age (1945-present): Nuclear technology era.

Ah birds and the evolution of grasses would be good adds, thanks. I only include entries that are meaningful to me which happens to be biased towards botany. I'd highly recommend anyone else keep their own lists though. Really gratifying to watch it grow over time

> first humans (5mya)

This might be a little early - Wikipedia says the genus Homo emerged from Australopithecus around 3.3 Ma (https://en.wikipedia.org/wiki/Homo).

Thanks, I'll look more into it. This is an area of active debate and research. Estimates have gone as far back as 7 Ma (e.g. this 2002 NYTimes article[0] says 5-7 Ma). Even the origins of Homo sapiens gets pushed around every other year (e.g. [1]).

[0] https://www.nytimes.com/2002/02/26/science/when-humans-becam...

[1] https://www.vox.com/science-and-health/2017/6/7/15745714/nat...

Also interesting, a timeline going the other way: https://en.m.wikipedia.org/wiki/Timeline_of_the_far_future

> shift to wetter climate makes Amazonia transition from grasslands to jungle (2k years ago)

Wait, so all those forest species living there...did they migrate from further north?

There is a lot of evidence that the rainforest is largely man made.

https://www.smithsonianmag.com/science-nature/pristine-untou...

A quick investigation on Wikipedia suggests that there are two competing schools of thought:

- the rainforest was somewhat smaller but still intact (contra the OP)

- the rainforest was reduced to small refuges separated by grassland

(op here)

> the rainforest was reduced to small refuges separated by grassland

This is the school of thought I've read about the most and my understanding. I never meant to imply that the entire rainforest didn't exist 2k years ago. Sorry for any confusion

Man have we observed and worked out a lot of stuff about our past. Not bad for a 3 inch chimp brained creature.

Here is one more list, detailed and comprehensive: https://www.southampton.ac.uk/~cpd/history.html it goes up to present days!

That’s excellent, thank you. My kid will love this, he’s just at that point where he’s starting to understand the short scale of human existence relative to what’s come before. Always looking for stuff that blows little minds.

Probably need to add a reference to the creation of ChatGPT as the last entry.

Why isn’t universe began (13.8bya) on there?

May be interesting to add some known future celestial events too.

So modern humans knew a green Sahara? Amazing to think about! I thought that was much older.

I was surprised to learn that as well. Apparently it’s a 20,000 year cycle.

https://news.mit.edu/2019/study-regulating-north-african-cli...

I believe people have speculated that desertification is where the idea of the Garden of Eden (that humans were expelled from) may have come from.

I feel like you should add the appearance of the first dinosaurs to this list (~240mya)!

Can't miss the ice age timelines. Please add those.

you should throw this 'README' up on github

Maybe, but this list is meant to be personalized to myself. Many have pointed out me missing the ice ages or all the major extinction events or whatever. I've only included events that I fully understand and provide meaningful context to me. If I had a GitHub readme, it'd inevitably turn into a very massive list and there's already Wikipedia pages that have done this more effectively

Instead what I hoped to inspire is for people to keep their own personal lists with items they find provide meaningful context. It's quite gratifying to watch it grow over time and also fully understand each entry

Continuation of that list with a little overlap:

https://github.com/pannous/hieros/wiki/inventions

    14 ka Shubayqa Jordan baked bread

    13 ka: beer in Haifa, Natufian

    13 ka: dentistry in italy (bitumen fillings) ⇨ 7000 BC in Baluchistan drill

    12 ka: chert arrows heads, with lateral notches, Khiamian? usage as awls and drills

    12-11 ka: Agriculture in the Fertile Crescent, Hureyra Karaca

    12–11 ka: Domestication of sheep in Southwest Asia (followed shortly by pigs, goats and cattle)

    11.5 ka houses were built on the ground level (before: half below ground)

    11.5-10.5 ka small female statuettes, symbolic burying of aurochs skulls (Khiamian)

    11.5 ka Totems (Shigir Idol), later in Americas

    11-8 ka: Domestication of rice in China

    11 ka: Constructed stone monument, megaliths – Göbekli Tepe, in Turkey

    11 ka: vat-fulls of porridge and stew, made from grain coarsely ground and processed on an almost industrial scale ⇨ gobekli

    11 ka: gobekli 10,000 grinding stones and nearly 650 carved stone platters and vessels, up to 200 litres of liquid

    9000 BC: Polished basalt axe & Jerf al Ahmar plaques proto writing?

    9000 BC: White ware burned lime containers

    9000 BC: small clay tokens for counting Mureybet

    9000 BC: Square Houses, explosive rapid growth of the use of cereals in near East

    9000 BC: Mudbricks, and clay mortar in Jericho.

    9000 BC: rammed earth walls in Fertile Crescent, later stabilized with lime or blood!

    8500 BC: millet cultivation 南庄头 Nánzhuāngtóu (& pottery)

    8000 BC: polished granite and alabaster jars (in Near East before pottery)

    8000 BC: Gesher basalt axes and various other tools, exported

    8000 BC Byblos arrowheads replaced the Mureybetian types, and other technological improvements

    8000–7500 BC: Proto-city – large permanent settlements, such as Tell es-Sultan (Jericho) and Çatalhöyük, Turkey.

    8000 BC: Patriarchic society Aşıklı Höyük??

    8000 BC: Oversea settlement of Mediteranian islands

    8th millennium bark cloth Çatalhöyük bast fibers from oak => barkcloth Guangxi ⋍5900 BC => Austronesia 3000 BC

    7900 BC: deep sea fishing (tuna), Franchthi Greece... see Whaling

    7500 BC: planned hunt & work camp : trading outpost(Umm Dabaghiya)

    7500 BC: Nabta Playa ceramics, megaliths, herding

    7500 BC: Neoliths reached Europe in Sesklo

    7000 BC: Tanned leather in the Indus Valley site of Mehrgarh, Pakistan.

    7000 BC: Dental drill in Mehrgarh, Pakistan.

    7000 BC: Alcohol fermentation – specifically mead, in China

    7000 BC: Sled dog and Dog sled, in Siberia.

    7000-6700 BC pottery reaching Hassuna, stone vessels and White Ware were still being used

    7000 BC two level houses in Çayönü Mureybet Beidha

    7000 BC kitchen & living rooms separated, upper levels used as granaries/workshops

    7th Millennium: copper hammering in Tell Sotto and Maghzaliyah

    7000-5000 BC Peiligang culture one of the oldest pottery in ancient China

    6500 BC Proper windows and doors in Basta near Beidha

    6500 BC Evidence of lead smelting in Çatalhöyük, Turkey

    6400 BC tholoi burial buildings in Yarim Tepe

    6200 BC Community vessels 85 liters, Nea Nikomedeia, Greece

    6200 BC Hip roof, clay mixed with hay over thatch (todo: older!)

    6200 BC spindle whorls for spinning wool, Nea Nikomedeia, Greece & Iran! =>

    6200 BC woolen threads, ropes, lines, leashes! (woolen cloth and laces only 2000 years later!)

    6000 BC: Whaling in Korea, Mediteranian, Basques and a bit later France (⇔ Megaliths!)

    6000 BC: Pottery Kiln in Mesopotamia Yarim Tepe(Iraq) after oven, metal furnace later

    6th Millennium: lead smelting and hot copper hammering in Anatolia and Yarim Tepe(Iraq)

    6000–4800 BC Samarra irrigation: Choga Mami 4700 BC  channels, flax?

    6,400 to 5,000 BC 'Ain Ghazal & Sha'ar HaGolan:

    6th millennium BC Yarmukian : 700 km trade network obsidian, pottery

    6th polished stone vessels made of alabaster (or marble) in Yarmukian

    6th Pebble streets in Yarmukian

    6th courtyard houses, ranging between 250 and 700 m² in Yarmukian

    6th Yarmukian : 4.15 m well

    6th Hassuna: jar burials with Venus & food => belief in the afterlife

    6th millennium BC: Irrigation in Khuzistan, Iran

    6000-3200 BC: Proto-writing found in present day Serbia and China; later in Iraq, Iran, Egypt and Pakistan.

    5500 BC: Barbie doll , Hamangia?

    5300 BC: War massacres genocide (again?)

    5300 BC: Hacilar heavy fortifications and small temple… newcomers!

    5000 BC: stamp seal with tally marks Tel Tsaf, Halaf culture

    5000 BC: silos with 200sq.m for 30 tons (20 families 1 year storage)

    5000 BC: Copper smelting in Serbia, after millennia of cold metal working

    5000 BC: Cotton thread, in Mehrgarh, Pakistan, connecting the copper beads of a bracelet.

    5000 BC: Seawall in Israel

    5th millennium BC: Lacquer in China

    5000–4500 BC: first preservation of old rowing oars in China!

    5000-4000 BC: two tier settlement hierarchy in Ubaid culture

    5000-4000 BC: centralized large sites of more than 10 hectares surrounded by smaller village sites of less than 1 hectare

    4800 BC: Sailing! Kuwait, Ubaid 3

    4800-4400 BC: City Walls to protect valuable oyster shell production in Dimini & Sesklo (founded 7500 BC!)

    4700 BC Irrigation at Choga Mami vs Samarra  channels quickly spreading to Halaf

    4500–3500 BC: Lost-wax casting in Israel or the Indus Valley

    4400 BC: Fired bricks in China.

    4th millennium specialized regional production centers:

    4000 BC?: silver Carpatho-Balkan zone, 3600BC Tepe Sialk

    4000 BC artificial harbor, Limantepe Izmir, Anatolia

    4000 BC: Probable time period of the first diamond-mines in the world, in Southern India.

    4000 BC: Paved roads, in and around the Mesopotamian city of Ur, Iraq (pebble roads see above)

    4000 BC: Plumbing. The earliest pipes were made of clay, and are found at the Temple of Bel at Nippur in Babylonia. Earthen pipes were later used in the Indus Valley c. 2700 BC for a city-scale urban drainage system, and more durable copper drainage pipes appeared in Egypt, by the time of the construction of the Pyramid of Sahure at Abusir, c.2400 BCE.

    4000–3500 BC: Wheel: potter's wheels in Mesopotamia and wheeled vehicles in Mesopotamia (Sumerian civilization), the Northern Caucasus (Maykop culture) and Central Europe (Cucuteni–Trypillia culture), reaching Harappa 3500 BC and China. Slow wheel tournette replaced by fast wheels after 3100 BC)

    4000-3500 BC: specialized ropes from fibers of reed, palms, flax, grass, papyrus, leather, or hair (China 2800BC)

    3500-2500 BC: Wheeled carts replacing drawn sledges

    3800-3500 BCE ox-plough Bubeneč, Czech Republic (replacing hoe 𓌸and hand-ard 𓆱 𓏏 𓏤 rods) !

    3630 BC: Silk garments (sericulture) in China

    3500 BC: Domestication of the horse (maybe 1000 years earlier) as pack & drough animal, riding maybe later.

    3500 BC: Wine as general anesthesia in Sumer, after millennia of usage as durable juice

    3500 BC: Very early Indus script signs in Pakistan http://news.bbc.co.uk/1/hi/sci/tech/334517.stm ⇔ King Scorpion

    3500 BC: Cylinder Seal emblem in Uruk and Susa after stamp seals in the Halaf culture

    3400-3100 BC: tattoos in southern Europe, after Ubaid and likely Upper Paleolithic

    3300 BC: Rise of Cycladic culture and Minoan civilization (Featuring 5500 BC Barbie doll , Hamangia)

    3000 BC: Internationally Standardized weights!

    2800 BC: copper mirror or earlier

    2600 BC: Cotton was woven and dyed for clothing in Harappa (see 5000BC Cotton threads)

    2600 BC: "fowl for fighting" Harappa

In case anybody else was puzzled, C4 grasses are those that "use the C4 carbon fixation pathway to increase their photosynthetic efficiency by reducing or suppressing photorespiration, which mainly occurs under low atmospheric CO2 concentration, high light, high temperature, drought, and salinity."

[1] https://en.wikipedia.org/wiki/List_of_C4_plants

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