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vox_mundi

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Re: Archaeology/Paleontology news
« Reply #200 on: January 03, 2020, 06:15:58 PM »
Extinction of Ice Age Mammals May Have Forced Humans to Invent Civilization
https://phys.org/news/2020-01-extinction-ice-age-mammals-humans.html

For 95% of our species' history, we didn't farm, create large settlements or complex political hierarchies. We lived in small, nomadic bands, hunting and gathering. Then, something changed.

We transitioned from hunter-gatherer life to plant harvesting, then cultivation and, finally, cities. Strikingly, this transition happened only after the ice age megafauna—mammoths, giant ground sloths, giant deer and horses—disappeared. The reasons humans began farming still remain unclear, but the disappearance of the animals we depended on for food may have forced our culture to evolve.

... Global warming at the end of the last glacial period, 11,700 years ago, probably made farming easier. Warmer temperatures, longer growing seasons, higher rainfall and long-term climate stability made more areas suitable for cultivation. But it's unlikely farming had been impossible everywhere. And Earth saw many such warming events – 11,700, 125,000, 200,000 and 325,000 years ago—but earlier warming events didn't spur experiments in farming. Climate change can't have been the only driver.

... Yet something changed. From 10,000 years ago onward, humans repeatedly abandoned the hunter-gatherer lifestyle for farming. It may be that after the extinction of mammoths and other megafauna from the Pleistocene epoch, and the overhunting of surviving game, the hunter-gatherer lifestyle became less viable, pushing people to harvest and then cultivate plants. Perhaps civilisation wasn't born out of a drive to progress, but disaster, as ecological catastrophe forced people to abandon their traditional lifestyles.
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kassy

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Re: Archaeology/Paleontology news
« Reply #201 on: January 06, 2020, 11:58:14 AM »
Early modern humans cooked starchy food in South Africa, 170,000 years ago

The discovery also points to food being shared and the use of wooden digging sticks to extract the plants from the ground

The inhabitants of the Border Cave in the Lebombo Mountains on the Kwazulu-Natal/eSwatini border were cooking starchy plants 170,000 years ago. This discovery is much older than earlier reports for cooking similar plants and it provides a fascinating insight into the behavioral practices of early modern humans in southern Africa.

...

The Hypoxis rhizomes were mostly recovered from fireplaces and ash dumps rather than from surrounding sediment. "The Border Cave inhabitants would have dug Hypoxis rhizomes from the hillside near the cave, and carried them back to the cave to cook them in the ashes of fireplaces," says Wadley. "The fact that they were brought back to the cave rather than cooked in the field suggests that food was shared at the home base. This suggests that the rhizomes were roasted in ashes and that, in the process, some were lost. While the evidence for cooking is circumstantial, it is nonetheless compelling."

https://www.sciencedaily.com/releases/2020/01/200102143424.htm
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Bruce Steele

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Re: Archaeology/Paleontology news
« Reply #202 on: January 06, 2020, 04:27:02 PM »
Here is a picture of Hypoxis.

https://www.smgrowers.com/products/plants/plantdisplay.asp?plant_id=4431

 I have eaten rhizomes from day lilies and hypoxis looks like another flower to keep in the garden as a potential food source. Day lilies taste like good potatoes.

vox_mundi

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Re: Archaeology/Paleontology news
« Reply #203 on: January 06, 2020, 05:07:53 PM »
^ Bruce:

Quote
... hypoxis looks like another flower to keep in the garden as a potential food source ...

You might want to be cautious about that. From your link ...
https://www.smgrowers.com/products/plants/plantdisplay.asp?plant_id=4431

Quote
... Other common names include Yellow Star and African Potato, although this last name should really not be used as the woody corm is not edible and actually may contain toxic compounds ...

If your looking for a perennial starch substitute I've had good luck with Cinnamon Vine, Air Potato
Latin: Dioscorea batata, Dioscorea polystachya

https://www.uaex.edu/yard-garden/resource-library/plant-week/cinnamon.aspx
http://www.eattheweeds.com/tag/cinnamon-vine-yam/

It's perennial; tolerates <0°F; forms both aerial and storage tubers; and tastes like potato
(If you need any starter tubers, I've got tons)

One-year-old roots weigh about 3 ounces, two-year-old roots, a pound. The root, in good soil, can grow up to three feet long and weight up to five pounds.  Its flavor is between a sweet potato and a regular potato. It is 20% starch, 75% water, 0.1% B1, and has 10 to 15 mgs vitamin C. The most common use is cooked like a potato.
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vox_mundi

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Re: Archaeology/Paleontology news
« Reply #204 on: January 06, 2020, 05:12:38 PM »
Tragedy of the Commons: Over-Hunting Walruses Contributed to the Collapse of Norse Greenland
https://phys.org/news/2020-01-over-hunting-walruses-contributed-collapse-norse.html

Latest research from the universities of Cambridge, Oslo and Trondheim has found that, for hundreds of years, almost all ivory traded across Europe came from walruses hunted in seas only accessible via Norse settlements in south-western Greenland.

Walrus ivory was a valuable medieval commodity, used to carve luxury items such as ornate crucifixes or pieces for games like chess and Viking favourite hnefatafl. The famous Lewis chessmen are made of walrus tusk.

However, the study also indicates that, as time wore on, the ivory came from smaller animals, often female; with genetic and archaeological evidence suggesting they were sourced from ever farther north—meaning longer and more treacherous hunting voyages for less reward.

Increasingly globalised trade saw elephant ivory flood European markets in the 13th century, and fashions changed. There is little evidence of walrus ivory imports to mainland Europe after 1400.

Dr. James H. Barrett, from the University of Cambridge's Department of Archaeology, argues that the Norse abandonment of Greenland may have been precipitated by a "perfect storm" of depleted resources and volatile prices, exacerbated by climate change.

Open Access: James H. Barrett et al, Ecological globalisation, serial depletion and the medieval trade of walrus rostra, Quaternary Science Reviews (2019)
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― Leonardo da Vinci

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vox_mundi

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Re: Archaeology/Paleontology news
« Reply #205 on: January 10, 2020, 08:43:00 PM »
Viking Runestone Linked to Fears of Climate Change
https://phys.org/news/2020-01-vikings-erected-runestone-climate-catastrophe.html

The Rok runestone, raised in the ninth century near the lake Vattern in south central Sweden, bears the longest runic inscription in the world with more than 700 runes covering its five sides.

It is believed to have been erected as a memorial to a dead son, but the exact meaning of the text has remained elusive, as parts are missing and it contains different writing forms.

Researchers at three Swedish universities now suspect the inscriptions are more of an allusion to an impending period of extreme winter, as the person who erected the stone tried to put their child's death into a larger perspective.

"The inscription deals with an anxiety triggered by a son's death and the fear of a new climate crisis similar to the catastrophic one after 536 CE," the authors wrote.

The sixth century crisis is believed to have been caused by a series of volcanic eruptions which dramatically influenced climate with lower average temperatures, ruined crops and ensuing hunger and mass extinctions.

The new interpretation is based on a collaborative approach between researchers from several disciplines, including philology, archaeology and the history of religion.



They take into account a number of events in the author of the text's lifetime, which could "have seemed extremely ominous."

"A powerful solar storm coloured the sky in dramatic shades of red, crop yields suffered from an extremely cold summer, and later a solar eclipse occurred just after sunrise," said Bo Graslund, professor in archaeology at Uppsala University.

"Even one of these events would have been enough to raise fears of another Fimbulwinter," Graslund added referring to a winter lasting three years in Norse mythology, a sign of the coming of Ragnarok.

Per Holmberg et al. The Rök Runestone and the End of the World, Futhark: International Journal of Runic Studies (2020)

See also: https://forum.arctic-sea-ice.net/index.php/topic,2164.msg241226.html#msg241226

-----------------------------

Mexico City Gold Was Aztec Loot Spanish Abandoned as They Fled in 1520
https://www.theguardian.com/world/2020/jan/10/mexico-city-gold-aztec-treasure-spanish-conquistadors

A new scientific analysis of a large gold bar found decades ago in downtown Mexico City has confirmed it was part of the plunder Spanish conquistadors abandoned as they beat a temporary retreat from the Aztec capital.



... A fluorescent X-ray chemical analysis was able to pinpoint its creation to 1519-20, according to Inah, which coincides with the time Cortés ordered gold objects stolen from an Aztec treasury to be melted down into bars for easier transport to Europe.

Historical accounts describe Cortés and his men as heavily weighed down by the gold they hoped to take with them as they fled the imperial capital during what is known today as the Sad Night, or Noche Triste, in Spanish.
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― Leonardo da Vinci

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

kassy

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Re: Archaeology/Paleontology news
« Reply #206 on: January 12, 2020, 10:13:11 PM »
Giant, Mysterious Blobs Are Lurking at the Edge of Earth’s Core

...

Over the years, better maps kept showing the same bloblike features. One huddles under Africa; the other is beneath the Pacific. They lurk where the planet’s molten iron core meets its rocky mantle, floating like mega-continents in the underworld. Their highest points may measure more than 100 times the height of Everest.

...

The connection between Hawaii and the Pacific blob might in turn solve another, more widespread puzzle.

Geochemists have long tried to explain why lava from Hawaii and other hot-spot locations such as Samoa, the Galápagos Islands, and Iceland has unique chemical signatures. For example, lava from these hot spots contains a relatively high concentration of helium-3—a primordial relic that predates the origin of the solar system. Scientists have found a similar pattern in neon isotopes, thought to be similarly ancient, and in isotopes of tungsten and xenon, both formed from the radioactive decay of other elements soon after the Earth was born.

In July, a team led by Curtis Williams, a geochemist at the University of California, Davis, published simulations that traced the plumes under hot spots back down through the flowing mantle. They found that these plumes reach all the way to the blobs, and bring unique chemistry up with them. “Whatever part of the mantle [the plumes are] coming from,” said Williams, “it’s really old.”

...

According to studies led by Trond Torsvik at the University of Oslo, the blobs also seem be linked to about two dozen surface regions called large igneous provinces—places where, at multiple times in Earth’s past, millions of cubic kilometers of lava oozed onto the surface as if through open wounds. Many of these events are themselves linked to mass extinctions like the Great Dying, the largest life-snuffing episode of the past half a billion years.

https://www.theatlantic.com/science/archive/2020/01/seismic-mystery-underneath-africa-and-pacific/604729/

See link for graphics and the more detailed explanation.
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Bruce Steele

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Re: Archaeology/Paleontology news
« Reply #207 on: January 17, 2020, 10:11:03 PM »
« Last Edit: January 17, 2020, 10:23:49 PM by Bruce Steele »

kassy

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Re: Archaeology/Paleontology news
« Reply #208 on: January 18, 2020, 11:48:26 AM »
Diving neaderthals came up before see #71 in this thread.

Free-Diving Neanderthals Gathered Tools From the Seafloor

New evidence suggests Neanderthals gathered clam shells and volcanic rock from the bottom of the Mediterranean, which they fashioned into tools. The work is yet more evidence that Neanderthals often ventured into the water, and it adds to the body of research showing that they were nothing like the unintelligent, uncoordinated clods they’ve long been portrayed to be.

...

a significant portion of the clam shells were collected as live animals, which required the Neanderthals to wade or even dive in shallow waters. These artefacts date back some 90,000 to 100,000 years to the Middle Paleolithic, predating the arrival of anatomically modern humans to Europe by around 60,000 years.

https://www.gizmodo.co.uk/2020/01/free-diving-neanderthals-gathered-tools-from-the-seafloor/

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0226690
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kassy

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Re: Archaeology/Paleontology news
« Reply #209 on: January 19, 2020, 03:28:09 PM »
There was a greek monkey mystery but we can cross it of now.  :)

How We Solved the 'Greek Monkey Mystery'

The blue monkeys painted on the walls of Akrotiri on the Greek island of Santorini are among many animals found in the frescoes of this 3,600-year-old city. Historians have studied the murals for decades since they were unearthed in the 1960s and 1970s on the island, which was once known as Thera. But when we and a team of other primatologists recently examined the paintings, we realised the monkeys could provide a clue that the Bronze Age world was much more globalised than previously thought.

Archaeologists had assumed the monkeys were an African species, with which the Aegean people that built Akrotiri probably came into contact via trade links with Egypt. But we think the paintings actually depict Hanuman langurs, a species from the Indian subcontinent. This suggests the Aegean people, who came from Crete and the Cycladic islands in the Aegean Sea, may have had trade routes that reached over 2,500 miles.

details and picture:
https://www.realclearscience.com/articles/2020/01/17/how_we_solved_the_greek_monkey_mystery_111259.html
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kassy

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Re: Archaeology/Paleontology news
« Reply #210 on: January 19, 2020, 03:32:00 PM »
Good question...

How Did Humans Boil Water Before the Invention of Pots?

...

It’s easy to imagine how prehistoric people could have roasted their food. It’s much harder to imagine how they could have boiled it without pottery. But that’s what Langley, who was helping lead a class of master’s students in archaeology, set out to attempt that October morning. Their boiling experiment was part of a course, and it took place at the York Experimental Archaeological Research Centre, a lakeside grove where researchers try to re-create the prehistoric by hafting arrowheads and weaving baskets out of reeds—and, in this case, boiling water. The students divided into groups of two or three, and they set out on this extremely simple yet daunting task

....

A couple of groups dug pits, filling them with coals and then lining them with either wet clay or a deer hide. Others poured water into birch bark or pig stomachs (procured from a Chinese supermarket). One group hung a deer hide from a tree and started heating small rocks in a fire—a technique inspired by the discovery of fire-cracked rocks in Paleolithic sites. These rocks had split and changed in distinct ways that suggested repeated heating and cooling. Archaeologists think that these stones were heated in fires and then dropped into water for cooking.

...

Another group was also attempting to boil water inside a deer hide hung directly over a fire—a technique admittedly less grounded in physical evidence from archaeological sites. In 2015, John Speth, a retired anthropologist at the University of Michigan, wrote a paper pointing out that you can actually boil water in a plastic water bottle.  ... YouTube videos and other evidence of people heating water in paper cups, coconut shells, bamboo tubes, wooden bowls, and even leaves. It turns out that as long as the cooking container is filled with water, it does not get hot enough to ignite.

...

However, ethnographers in the 19th and 20 centuries documented the Celts, Assiniboin, Cree, Ojibwa, and Blackfeet cooking without stones in birch bark, hides, and animal stomachs. These organic materials would have rotted, of course, leaving no artifacts for archaeologists to study.

https://www.theatlantic.com/science/archive/2020/01/how-did-humans-cook-before-the-invention-of-pots/605008/
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Bruce Steele

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Re: Archaeology/Paleontology news
« Reply #211 on: January 19, 2020, 03:58:21 PM »
Kassy, The Chumash were a group of Calif. Native Americans who did not use pottery. To boil water they used tar lined basketry and added fire heated small, smooth, round serpentine rocks to boil water or heat their staple food, acorn mush. The ethnographic record, the basketry and the stones are all in archeological collections.
 I have been collecting the stones from my field. The pigs like to pick them up in their mouths and sometimes they end up in the water troughs. I have a collection of them and plan to use them on a batch of acorn mush but I haven’t gotten around to it yet.

sidd

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Re: Archaeology/Paleontology news
« Reply #212 on: January 19, 2020, 08:59:20 PM »
Re: The pigs like to pick them up in their mouths

I wonder why. You haven't licked one, have you ?

sidd

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Re: Archaeology/Paleontology news
« Reply #213 on: January 20, 2020, 05:34:18 AM »
Re: The pigs like to pick them up in their mouths

Pigs are very intelligent and social. Could it be that they observed you picking up stones and wanted to help you?
Perhaps they were licking to see what so special about those stones.
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sidd

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Re: Archaeology/Paleontology news
« Reply #214 on: January 20, 2020, 08:11:56 AM »
I meant licked a stone, not a pig ...

sidd

KiwiGriff

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Re: Archaeology/Paleontology news
« Reply #215 on: January 20, 2020, 09:53:18 AM »
Quote
Hāngi (Māori pronunciation: [ˈhaːŋi]) is a traditional New Zealand Māori method of cooking food using heated rocks buried in a pit oven, called an umu.[1] It is still used for large groups on special occasions.[2]
To "lay a hāngi" or "put down a hāngi" involves digging a pit in the ground, heating stones in the pit with a large fire, placing baskets of food on top of the stones, and covering everything with earth for several hours before uncovering (or lifting) the hāngi.[3]
Prior to colonisation and the introduction of metals and wire, food was laid between bark, large leaves and other vegetation.

The effect is like steaming.
When done well it is very tasty  if somewhat earthy flavored .
Polynesians in the islands also do something very similar called an umu but it is done above ground using banana leaves piled over hot stones.

Animals can be driven crazy by placing too many in too small a pen. Homo sapiens is the only animal that voluntarily does this to himself.
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nanning

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Re: Archaeology/Paleontology news
« Reply #216 on: January 20, 2020, 11:24:47 AM »
@sidd indeed, sorry. In that case they were perhaps helping Bruce in bringing stones from the field.
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
Why do you keep accumulating stuff?

Bruce Steele

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Re: Archaeology/Paleontology news
« Reply #217 on: January 20, 2020, 09:44:02 PM »
Sidd, The stones are very smooth and have a waxy feel to them. Just a hunch but I think they like the smooth feel of the stones. I like my little experiments so I will boil one awhile and see what rolling one around in my mouth feels like. Most rocks would crack if you heated them and then dropped them in water. Some risk of splashing yourself with boiling water.
 I make metates ,mortars and pestles. No power tools. I usually use a metal hammer and chisel to peck the hole and smooth the edges with a stone pestle that will match the bowl when finished. I made a very big metate without any metal tools. I have been looking at old millstones and one of my projects is making some functional  stone flour mills that can be either human or animal powered. I have mentioned that I think somehow providing for the needs of those who come after the bottleneck is something I think about. Pecking out a stone bowl and pestle isn’t that difficult but it isn’t very good for flour production. A metate works better but still it is a lot of work to even make flour for a few tortillas.
  A stone flour mill that can produce several pounds of flour a day would seem to be something a group of people could use , someday . Anyway they will last and
 even if purely an anachronism they will be pretty to look at.

 

KiwiGriff

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Re: Archaeology/Paleontology news
« Reply #218 on: January 20, 2020, 10:05:51 PM »
You need to use igneous rocks if you want to heat them in a fire.
 
Animals can be driven crazy by placing too many in too small a pen. Homo sapiens is the only animal that voluntarily does this to himself.
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Re: Archaeology/Paleontology news
« Reply #219 on: January 21, 2020, 12:45:36 AM »
some years ago I was helping at a Ayahuasca ceremony. It was to be followed by a sweat lodge but the guy involved wanted the ceremony shortened and to start the sweat early . I said no .. he got  mad so I told him the sweat would not take place . He was determined it would but minutes later he was calling me the devil .. all his hot stones had shattered .. never before .... b.c.
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kassy

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Re: Archaeology/Paleontology news
« Reply #220 on: January 22, 2020, 06:45:12 PM »
Earth's oldest asteroid impact 'may have ended ice age'

Scientists have identified the world's oldest asteroid crater in Australia, adding it may explain how the planet was lifted from an ice age.

The asteroid hit Yarrabubba in Western Australia about 2.2 billion years ago - making the crater about half the age of Earth, researchers say.

Their conclusion was reached by testing minerals found in rocks at the site.

...

"The age of the [crater] corresponds pretty precisely with the end of a potential global glacial period," Prof Kirkland said.

"So the impact may have had significant changes to our planetary climate."

Using computer modelling, the team calculated that the asteroid struck a kilometres-thick ice sheet covering the Earth. The event would have released huge volumes of water vapour, a greenhouse gas, into the atmosphere.

This could have helped the planet's warming during the Proterozoic era - a stage when oxygen had just appeared in the atmosphere and complex life had not yet formed.

https://www.bbc.com/news/world-australia-51201168
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kassy

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Re: Archaeology/Paleontology news
« Reply #221 on: January 24, 2020, 10:19:32 AM »
The fungal gap in the fossil record has been closed sith some recent finds.
Note the headline is crap because we already knew this from the molecular clock:

New Discovery Proves Fungi Were Around Way Earlier Than Anyone Expected

Mysterious fossils that had been sitting idle for decades in a Belgian museum have just been identified, and they're something wonderful. According to new analysis, these are fungal structures dating between 715 and 810 million years ago - making them some of the earliest fungus specimens ever recorded.

...
Last year, however, a discovery indicated otherwise. An international team of scientists led by Corentin Loron of the University of Liège in Belgium identified fossils of fungus from Canada, dating back to between 900 million and 1 billion years ago - early in the Neoproterozoic Era. They called the fungus Ourasphaira giraldae.

Now, with a new and more comprehensive array of tests, fossils collected from the Democratic Republic of the Congo many years ago have delivered the surprise discovery of fungus fossils that could be nearly as old. The new fungus has yet to be given a species name.

...

As we have previously reported, we know fungus was around when the first plants began to emerge around 500-600 million years ago. However, the fungal molecular clock had already suggested these life forms should have been around sooner.

This clock is the mutation rate of biomolecules in DNA, which can be used to determine the evolutionary history of an organism. In the case of fungus, if it had emerged around the same time as plants, its molecular clock would reflect this.

Instead, the DNA of fungus indicated that it made its first appearance over 1 billion years ago. This discrepancy between the fossil record and the molecular clock has been a huge puzzle.

https://www.sciencealert.com/new-discovery-proves-fungi-were-around-way-earlier-than-anyone-expected
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kassy

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Re: Archaeology/Paleontology news
« Reply #222 on: January 26, 2020, 11:31:32 AM »
Human Ancestors Caused Animal Extinctions Millions of Years Before We Even Arrived

...

By examining the fossil record in East Africa, biologists have been able to trace a decline in carnivores that correlates with an increase in hominin brain size and vegetation changes - but not with climate or weather changes, as is commonly found.

This, the researchers say, can be interpreted as a connection between hominin activity and carnivore extinctions.

"Our analyses show that the best explanation for the extinction of carnivores in East Africa is … that they are caused by direct competition for food with our extinct ancestors," said computational biologist Daniele Silvestro of the University of Gothenburg in Sweden.

...

"By investigating the African fossils, we can see a drastic reduction in the number of large carnivores, a decrease that started about 4 million years ago," said palaeontologist Lars Werdelin of the Swedish Museum of Natural History.

"About the same time, our ancestors may have started using a new technology to get food called kleptoparasitism."

You probably know kleptoparasitic animals very well. Seagulls, swooping in to nick your chips. Hyenas and lions, which steal each other's kills willy-nilly. The less said about the poor, displaced Australian white ibis the better.

https://www.sciencealert.com/human-ancestors-drove-animals-to-extinction-millions-of-years-ago
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kassy

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Re: Archaeology/Paleontology news
« Reply #223 on: January 28, 2020, 03:03:21 PM »
More on Neanderthals:

A Siberian cave contains clues about two epic Neandertal treks

Neandertals were epic wanderers.

These ancient hominids took a 3,000- to 4,000-kilometer hike from Eastern Europe to the Altai Mountains in southern Siberia around 60,000 years ago, a new study concludes. The evidence is in their handiwork

...

Neandertals at sites in what’s now Crimea and the northern Caucasus, just north of the Black Sea in Eastern Europe, and others who occupied Chagyrskaya Cave in southern Siberia crafted comparable stone tools between around 59,000 and 49,000 years ago

...

That wasn’t the first such journey for our extinct evolutionary relatives. European Neandertals already had migrated into southern Siberia more than 100,000 years ago. But the Neandertals who reached Siberia’s Denisova Cave (SN: 1/30/19) — about 100 kilometers east of Chagyrskaya Cave — made a different type of stone tools, suggesting these Neandertals were part of a separate migration to the region, the researchers say.

For details:
https://www.sciencenews.org/article/siberia-cave-contains-clues-about-two-epic-neandertal-treks

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kassy

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Re: Archaeology/Paleontology news
« Reply #224 on: January 30, 2020, 03:16:49 PM »
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kassy

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Re: Archaeology/Paleontology news
« Reply #225 on: January 31, 2020, 10:21:23 AM »
Previous efforts simply assumed that Africans largely lacked Neanderthal DNA. To get more reliable numbers, Princeton University evolutionary biologist Joshua Akey compared the genome of a Neanderthal from Russia’s Altai region in Siberia, sequenced in 2013, to 2504 modern genomes uploaded to the 1000 Genomes Project, a catalog of genomes from around the world that includes five African subpopulations. The researchers then calculated the probability that each stretch of DNA was inherited from a Neanderthal ancestor.

The researchers found that African individuals on average had significantly more Neanderthal DNA than previously thought—about 17 megabases (Mb) worth, or 0.3% of their genome. They also found signs that a handful of Neanderthal genes may have been selected for after they entered Africans’ genomes, including genes that boost immune function and protect against ultraviolet radiation.

...

The best fit model for where Africans got all this Neanderthal DNA suggests about half of it came when Europeans—who had Neanderthal DNA from previous matings—migrated back to Africa in the past 20,000 years. The model suggests the rest of the DNA shared by Africans and the Altai Neanderthal might not be Neanderthal at all: Instead, it may be DNA from early modern humans that was simply retained in both Africans and Eurasians—and was picked up by Neanderthals, perhaps when moderns made a failed migration from Africa to the Middle East more than 100,000 years ago.

Akey’s study might help explain another “head scratcher,” says computer biologist Kelley Harris of the University of Washington, Seattle. Studies had suggested East Asians have 20% more Neanderthal DNA than Europeans, she notes. “Europe is where Neanderthal remains are found, so why wouldn’t Europeans have more Neanderthal ancestry than any other group?”

By suggesting that Europeans introduced Neanderthal sequences into Africa, the new study points to an explanation: Researchers previously assumed that Neanderthal sequences shared by Europeans and Africans were modern and subtracted them out. After correcting for that bias, the new study found similar amounts of Neanderthal DNA in Europeans and Asians—51 and 55 Mb, respectively. It’s a “convincing and elegant” explanation, Harris says.

https://www.sciencemag.org/news/2020/01/africans-carry-surprising-amount-neanderthal-dna

and

Without knowing exactly what a full Neanderthal genome would look like, or how much of it is in our own bodies, researchers traditionally relied on statistical methods that compare various DNA sequences against a reference point. By assuming our modern genetic heritage flowed with a migrating human population, from west to east, ancestors who remained in Africa established a blank slate as far as Neanderthal genes went.

Using the results of those studies only verified those assumptions further.

With advances in Neanderthal DNA analysis in mind, Chen and her colleagues took a different approach based on what's known as identity by descent (IBD).

Rather than rely on assumed reference points to make comparisons, the team went straight to the Neanderthal's sequenced genome and applied the principle that close family relationships are more likely to have more genetic sequences in common.

https://www.sciencealert.com/people-with-an-african-ancestry-also-have-a-few-neanderthal-genes-after-all?perpetual=yes&limitstart=1
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vox_mundi

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Re: Archaeology/Paleontology news
« Reply #226 on: February 04, 2020, 05:00:30 PM »
7,000-year-Old Well is Oldest Wooden Structure Ever Discovered
https://www.cnn.com/2020/02/04/europe/wooden-well-oldest-czech-republic-scli-intl-scn/index.html


The well was built by farmers around 5256 B.C., researchers said.

Archaeologists have discovered a 7,000-year-old Neolithic well in eastern Europe, which they believe is the oldest wooden structure in the world.

The square well was built with oak by farmers around 5256 B.C., according to researchers who pinpointed its origin after analyzing the tree rings in the wood, which is the scientific method known as dendrochronology. The well's age makes it the oldest dendrochronologically dated archaeological wooden construction worldwide, according to the researchers in the Czech Republic.

"It is interesting that the corner posts were made of previously felled trunks, namely from the trunk which had been cut in the autumn or winter 5259 B.C. or the winter of early 5258 B.C.," said Michal Rybníček of the Department of Wood Science at Mendel University.

Its design shines a light on technical skills that researchers didn't think Neolithic people possessed.

"The design consists of grooved corner posts with inserted planks. This type of construction reveals advanced technical know-how and, till now, is the only known type from this region and time period," the authors wrote.

According to experts, the well indicates that whoever built it was able to process the surface of felled trunks with utmost precision, given that they only had tools made of stone, bone, horn, or wood.

"The shape of the individual structural elements and tool marks preserved on their surface confirm sophisticated carpentry skills," the authors wrote.
It is the third well from the early Neolithic period found in the Czech Republic in the past four years.
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Re: Archaeology/Paleontology news
« Reply #227 on: February 04, 2020, 07:04:28 PM »
^^
WOW. What an awesome find.
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Re: Archaeology/Paleontology news
« Reply #228 on: February 05, 2020, 12:12:26 AM »
^^
It's the same technology they applied to mill pond dams here that were built ~200 years ago. Slotted oak uprights and slats that could be adjusted for water flow.


I've seen it in very early European settlements in North America, (but not at L'Anse aux Meadows).
Strangely I've never seen evidence of similar technology at First Nations sites.
Terry

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Re: Archaeology/Paleontology news
« Reply #229 on: February 05, 2020, 06:58:09 AM »
^^
Boring a permanent hole in the ground for water extraction is a technology of control of nature (supremacy). It is civilisation behaviour I think. It is better, like other lifeforms like us do, to find a stream or lake. That's 'natural'.
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vox_mundi

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Re: Archaeology/Paleontology news
« Reply #230 on: February 05, 2020, 06:32:28 PM »
Neanderthals’ Relatives Climbed an Erupting Volcano 350,000 Years Ago
https://arstechnica.com/science/2020/02/neanderthals-relatives-climbed-an-erupting-volcano-350000-years-ago/

Roccamonfina volcano, about 60km northwest of Vesuvius, erupted violently around 350,000 years ago. Pyroclastic flows—deadly torrents of hot gas and volcanic ash—raced down the sides of the mountain. But within a few days, a small group of hominins trekked across the layer of ash and pumice that covered the steep mountainside. Recent analysis and some newly identified prints suggest that the intrepid (or reckless) hominins may have been Homo heidelbergensis who lived and hunted near the volcano.

Another layer of ash later covered the slope, sealing away at least 81 tracks until the early 1800s, when erosion revealed them to the local humans. The tracks record where at least five climbers, all with different foot sizes, walked down the steep, ash-covered hillside. One trail zigzags back and forth downhill, and you can easily picture climbers carefully working their way diagonally across the slope. Along another, more curving path, there are still handprints where the climbers reached out to steady themselves, and a slide mark reveals where one climber slipped.

The ash must have been cool enough to walk on but still soft enough to preserve tracks—very detailed ones, in a few cases. According to ichnologist Adolfo Panarello (of University of Cassino and Southern Latium) and his colleagues, that must have happened within a few days of the pyroclastic flow; Roccamonfina may even still have been erupting. In the 1800s, people living around the now-extinct volcano were sure that only the devil could have left those tracks.

... The footprints most likely belong to an evolutionary relative of ours: Homo heidelbergensis, the species that gave rise to Neanderthals around 400,000 years ago.

One of the newly identified prints at the site records a surprising amount of detail about a climber's right foot: the wide heel, the low arch, and the base of the big toe. Overall, Panarello and his colleagues say it looks very similar to the feet of 430,000 year-old H. heidelbergensis fossils from Sima de los Huesos cave in Spain. That lines up with a 2016 study, which found that the short, wide shape of the footprints matched well with the size of fossil feet from H. heidelbergensis elsewhere in Europe.

Around the time of the eruption, some H. heidelbergensis groups already looked a lot like Neanderthals—including the Sima de los Huesos group, whose feet look so much like the Roccamonfina prints. But at the same time, other groups in other parts of Europe still looked more like older hominins: including the 400,000-year-old skull from Ceprano Cave, which is only about 70km (42 miles) from Roccamonfina in northern Italy.

... Archaeologists have found stone tools along the trackways in the same rock layer, and similar tools have turned up at a site nearby, although it’s not clear how old those tools are.

As they climbed the freshly buried slope, they weren't fleeing in terror (it would have been much too late for that anyway). Based on the shape of the impressions and the distance between them, the climbers were actually walking at a fairly leisurely pace.

They may even have been hunting. Hoofprints also dot the rock nearby, and a couple of large canine paw prints also pass close to the human tracks. But unlike at White Sands, New Mexico, the footprints don't show any confrontations between the hominins and their potential prey (or potential rivals). That means we can't say for sure that these hominins ventured onto the volcano in search of a meal.

Adolfo Panarello, et.al. On the devil's tracks: unexpected news from the Foresta ichnosite (Roccamonfina volcano, central Italy), Journal of Quaternary Science, 2020



----------------------------

Pyroclastic flow. Mega-fauna. Wild Boar. I'm thinking they were up there for an all-you-can-eat 'barbecue' 
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vox_mundi

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Re: Archaeology/Paleontology news
« Reply #231 on: February 07, 2020, 06:07:57 PM »
Scientists Resurrected a Wrangel Island Mammoth's Mutated Genes
https://phys.org/news/2020-02-scientists-resurrected-wrangel-island-mammoth.html

Some 4,000 years ago, a tiny population of woolly mammoths died out on Wrangel Island, a remote Arctic refuge off the coast of Siberia.

They may have been the last of their kind anywhere on Earth.

To learn about the plight of these giant creatures and the forces that contributed to their extinction, scientists have resurrected a Wrangel Island mammoth's mutated genes. The goal of the project was to study whether the genes functioned normally. They did not.

The research builds on evidence suggesting that in their final days, the animals suffered from a medley of genetic defects that may have hindered their development, reproduction and their ability to smell.

The problems may have stemmed from rapid population decline, which can lead to interbreeding among distant relatives and low genetic diversity—trends that may damage a species' ability to purge or limit harmful genetic mutations.

"The key innovation of our paper is that we actually resurrect Wrangel Island mammoth genes to test whether their mutations actually were damaging (most mutations don't actually do anything)," says lead author Vincent Lynch, Ph.D., an evolutionary biologist at the University at Buffalo. "Beyond suggesting that the last mammoths were probably an unhealthy population, it's a cautionary tale for living species threatened with extinction: If their populations stay small, they too may accumulate deleterious mutations that can contribute to their extinction."

The study was published on Feb. 7 in the journal Genome Biology and Evolution.



Erin Fry et al. Functional architecture of deleterious genetic variants in the genome of a Wrangel Island mammoth, Genome Biology and Evolution (2019).

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vox_mundi

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Re: Archaeology/Paleontology news
« Reply #232 on: February 07, 2020, 10:40:53 PM »
Scientists Grow Date Palm Plants from 2,000-Year-Old Seeds
https://phys.org/news/2020-02-scientists-date-palm-year-old-seeds.html



Methuselah, Adam, Jonah, Uriel, Boaz, Judith and Hannah—all sat dormant in Judea since biblical times. Now scientists have resurrected them in the hopes of better understanding their vanished lineage

These seven ancient emissaries are date palm plants, now all growing in the southern Israeli community of Ketura. Methuselah came first. He was planted in 2005 from an approximately 2,000-year-old seed found buried under rubble at the ancient fortress of Masada overlooking the Dead Sea.

Since then, he has been joined by the others. As part of a long-term project at the Arava Institute for Environmental Studies in Israel, scientists hope to breed Judean date palms—a variety that was praised in antiquity for its sweetness, large size, long shelf life, and supposed ability to fight disease, but which went extinct hundreds of years ago when repeated conflict wiped out the date plantations.

The ages of the seven successfully sprouted ancient seeds range from around 2,400 to 1,800 years old. The seeds came from three archeological sites in the Judean desert, including Qumran, where the Dead Sea Scrolls were discovered.

The resurrected date palms include both female and male trees, and the researchers are hoping that the trees will eventually produce fruit together. However, the new dates may not be the same as what people ate in ancient times, since ancient date growers would probably have cultivated shoots from select female plants, which perished long ago. The plants grown from their daughter seeds may not have the same qualities. Still, they may display some characteristics that have been lost in modern date varieties.

Open Access: Sarah Sallon et al. Origins and insights into the historic Judean date palm based on genetic analysis of germinated ancient seeds and morphometric studies, Science Advances (2020).
https://advances.sciencemag.org/content/6/6/eaax0384
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Tor Bejnar

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Re: Archaeology/Paleontology news
« Reply #233 on: February 08, 2020, 10:36:25 PM »
Ancient marine reptile thalattosaur discovery stuns palaeontologists with its 'needle-like' snout
ABC (Australia)

Quote
An iguana-like creature with a needle-sharp snout has been confirmed from a fossilised skeleton as a species of the marine reptile thalattosaur, previously unknown to science, that roamed the coast of what is now Alaska some 200 million years ago.
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kassy

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Re: Archaeology/Paleontology news
« Reply #234 on: February 11, 2020, 08:26:24 PM »
Here is some recent stuff...

Himalayan glacier shows evidence of start of Industrial Revolution

...

Dasuopu -- at 7,200 meters or 23,600 feet above sea level -- is the highest-altitude site in the world where scientists have obtained a climate record from an ice core. Dasuopu is located on Shishapangma, one of the world's 14 tallest mountains, which are all located in the Himalayas.

For this study, the research team analyzed one core taken from Dasuopu in 1997 for 23 trace metals.

The ice cores operate as a sort of timeline, and show new ice forming in layers on the glacier over time. It is possible for researchers to tell almost the precise year a layer of the glacier formed because of environmental clues like snowfall or other known natural or human-made disasters. The ice the researchers evaluated formed between 1499 and 1992, the team determined. Their goal was to see whether human activity had affected the ice in any way, and, if so, when the effects had begun.

Their analysis showed it had: The team found higher-than-natural levels of a number of toxic metals, including cadmium, chromium, nickel and zinc, in the ice starting at around 1780 -- the very start of the Industrial Revolution in the United Kingdom. Those metals are all byproducts of burning coal, a key part of industry at the end of the 18th century and throughout the 19th and 20th centuries.

The researchers found that those metals were likely transported by winter winds, which travel around the globe from west to east.

They also believe it is possible that some of the metals, most notably zinc, came from large-scale forest fires, including those used in the 1800s and 1900s to clear trees to make way for farms.

"What happens is at that time, in addition to the Industrial Revolution, the human population exploded and expanded," Gabrielli said. "And so there was a greater need for agricultural fields -- and, typically, the way they got new fields was to burn forests."

...

https://www.sciencedaily.com/releases/2020/02/200210153343.htm
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kassy

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Re: Archaeology/Paleontology news
« Reply #235 on: February 15, 2020, 12:12:45 PM »


Any number of now-extinct human lineages that once existed within Africa may have hybridized with modern humans there as well. However, the sparse nature of the ancient human fossil record in Africa makes it difficult to identify DNA from such "ghost lineages" in modern humans.

Instead of hunting for ancient human fossils across Africa, the scientists looked for genetic traces of ghost lineages in modern Africans. They compared 405 genomes from modern people from West Africa with ones from fossils of Neanderthals and Denisovans, focusing on DNA that stood out from the West African genomes roughly as much as Neanderthal and Denisovan DNA did from modern human genomes overall.

The researchers detected statistical anomalies they suggested were best explained by interbreeding between West Africans and an unknown ancient human lineage whose ancestors diverged from those of modern humans before the split between Neanderthals and modern humans. Four West African groups -- Yoruba in southwestern Nigeria, Esan in southern Nigeria, Gambians in western Gambia, and Mende in Sierra Leone -- may derive 2% to 19% of their DNA from a ghost lineage, the researchers said.

...

A number of ghost lineage genetic variants were unusually common in the Yoruba and Mende genomes, suggesting they might confer some evolutionary advantages. These included genes involved in tumor suppression, male reproduction and hormone regulation.

...

The scientists estimated this ghost lineage diverged from the ancestors of Neanderthals and modern humans up to 1.02 million years ago and interbred with the ancestors of modern West Africans from 124,000 years ago up to the present day. "One limitation of our study is that we have mainly sampled present-day West African populations," Sankararaman said. They don't know yet how far the ghost lineage spread across Africa, he said.

https://www.insidescience.org/news/genetic-traces-mysterious-human-lineage-detected-people-living-west-africa
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kassy

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Re: Archaeology/Paleontology news
« Reply #236 on: February 16, 2020, 12:36:00 PM »
5,200-Year-Old Grains In Eastern Altai Mountains Redate Trans-Eurasian Crop Exchange

...

This new study, led by scientists from the Chinese Academy of Sciences and the Max Planck Institute for the Science of Human History, provides details of recently recovered ancient grains from the far northern regions of Inner Asia. Radiocarbon dating shows that the grains include the oldest examples of wheat and barley ever recovered this far north in Asia, pushing back the dates for early farming in the region by at least a millenium. These are also the earliest domesticated plants reported from the northern half of Central Asia, the core of the ancient exchange corridor. This study pulls together sedimentary pollen and ancient wood charcoal data with archaeobotanical remains from the Tiangtian archaeological site in the Chinese Altai Mountains to reveal how humans cultivated crops at such northern latitudes. This study illustrates how adaptable ancient crop plants were to new ecological constraints and how human cultural practices allowed people to survive in unpredictable environments.

...

this study illustrates that ancient peoples were cultivating these grasses over five and a half thousand kilometers to the northeast of where they originally evolved to grow. In this study, Dr. Xinying Zhou and his colleagues integrate paleoenvironmental proxies to determine how extreme the ecology was around the archaeological cave site of Tangtian more than five millennia ago, at the time of its occupation. The site is located high in the Altai Mountains on a cold,dry landscape today; however, the study shows that the ecological setting around the site was slightly warmer and more humid at the time when people lived in and around this cave.

The slightly warmer regional conditions were likely the result of shifting air masses bringing warmer, wetter air from the south. In addition to early farmers using a specific regional climate pocket to grow crops in North Asia, analysis showed that the crops they grew evolved to survive in such northern regions. The results of this study provide scholars with evidence for when certain evolutionary changes in these grasses occurred, including changes in the programed reliance of day length, which signals to the plant when to flower, and a greater resistance to cold climates.

https://www.eurasiareview.com/16022020-5200-year-old-grains-in-eastern-altai-mountains-redate-trans-eurasian-crop-exchange/
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kassy

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Re: Archaeology/Paleontology news
« Reply #237 on: February 21, 2020, 02:44:24 PM »
Dozens of ancient Egyptian graves found with rare clay coffins

Archaeologists have discovered 83 graves from ancient Egypt, but the human remains weren't interred in sarcophagi, as is often the case. Rather, the deceased were buried in clay coffins, according to the Egyptian Ministry of Antiquities.

Eighty of the graves date to the civilization of Bhutto, or Lower Egypt, during the first half of the fourth millennium B.C. The burials were found during archaeological excavations in the Dakahlia governorate of northern Egypt, not too far from the Mediterranean Sea.

...

The Naqada culture is old, even by Egyptian standards, dating to predynastic Egypt during the Chalcolithic era, or Copper Age. The new discovery indicates that many people lived in this area at that time, said Waziri, who suspects that even more graves will be found at the site.

The excavated Naqada III graves contain a trove of artifacts. So far, excavators have discovered handmade pottery, oyster shells, a bowl in the shape of a tilapia and two bowls — one rectangular and one circular — of kohl, a cosmetic that Egyptians painted around their eyes, as well as a kohl plate, Ayman Ashmawy, head of the Egyptian Antiquities Sector at the Supreme Council of Antiquities, said in the statement.

...

a handful date to the Hyksos period, or about 1630 to 1523 B.C. These artifacts included ovens and stoves, the remains of mud-brick building foundations and four mud-brick burials

https://www.livescience.com/ancient-egypt-clay-graves.html
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kassy

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Re: Archaeology/Paleontology news
« Reply #238 on: February 21, 2020, 02:54:32 PM »
Incredibly Well-Preserved Ice Age Frozen Bird Found In Siberian Permafrost

The bird was discovered by a team of local fossil ivory hunters in the village of Belaya Gora in Yakutia, northern Russia. Realizing they had stumbled across something significant, they passed the specimen onto scientists at the Centre for Palaeogenetics in Sweden.

Reported in the journal Communications Biology, radiocarbon dating revealed that the bird was alive approximately 44,000 to 49,000 years ago. Acting like a refrigerator, the conditions have preserved the bird incredibly well after all these millennia, complete with intact feathers, nails, skin, and soft tissue. Permafrost creates the ideal conditions to preserve organic matter, providing sub-zero temperatures that are low enough to stave off most bacterial and fungal growth that would otherwise decompose the body, but not cold enough to damage the tissues.

The bird's remarkable condition also means it’s a treasure trove for researchers looking to study the genetics of ancient animals. They also managed to extract DNA from the carcass, revealing that the bird was a species of passerine known as a horned lark (Eremophila alpestris). The genetic data showed that the bird was the ancestor of two different subspecies of horned lark, one that today lives in northern Russia and another that inhabits the Mongolian steppe.

“The next step is to sequence the complete genome of this bird. This would allow us to obtain direct estimates of mutation rates but also to further examine the timing and evolution of larks in Eurasia,” Nicolas Dussex, PhD, a postdoctoral researcher at the Centre for Palaeogenetics, told IFLScience.

more on
https://www.iflscience.com/plants-and-animals/incredibly-wellpreserved-ice-age-frozen-bird-found-in-siberian-permafrost/
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kassy

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Re: Archaeology/Paleontology news
« Reply #239 on: February 22, 2020, 09:59:28 AM »
Humans Bred With a Mysterious Archaic Population in Earliest Known Interbreeding Event

...

700,000 years ago, according to a new study, a population of ancient humans mated with a distinct unknown population that had separated from other human species at least 1 million years prior.

"This continues the story that we've been seeing in studies throughout the past decade: There's lots more interbreeding between lots of human populations than we were aware of ever before," Alan Rogers, an anthropologist and the lead author of the new study, told Business Insider.

"This discovery has pushed the time depth of those interbreedings much further back."

...

But the interbreeding event that Rogers and his colleagues found was far, far older. In that case, a group of humans who were ancestors of both Neanderthals and Denisovans (the study authors nicknamed them "neandersovans") interbred with their predecessor species about 744,000 years ago.

Those predecessors, in turn, were part of a "superarchaic" group in Eurasia that was between 20,000 and 50,000 people in size.

A major implication of the study, then, is that human populations migrated from Africa to Eurasia three times during our long evolutionary history: once 1.9 million years ago, again 700,000 years ago, and then a final time 50,000 years ago.

The first of these waves involved the "superarchaics." Then the neandersovans followed 700,000 years ago; they likely separated from the modern human lineage before they migrated north, the study said.

...

Rogers' team's discovery came after they compared publicly available modern human DNA with ancient DNA. The analysis showed at least four watershed moments in which genetic material passed from one human species to another over the past 1 million years.

Three of those moments matched the results of other studies. But the oldest instance was a new find.

In addition to representing the oldest evidence of human interbreeding on record, the finding is also surprising because the two populations that mated were far less closely related than other human groups previously known to have interbred.

Whereas modern humans and Neanderthals had been on separate branches of the evolutionary tree for about 750,000 years when they interbred, the newly discovered population and the neandersovans had been separated for more than 1 million years.

https://www.sciencealert.com/the-earliest-known-inter-breeding-event-was-between-humans-and-a-mysterious-population

https://advances.sciencemag.org/content/6/8/eaay5483
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vox_mundi

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Re: Archaeology/Paleontology news
« Reply #240 on: February 24, 2020, 06:02:58 PM »
One Billion-Year-Old Green Seaweed Fossils Identified, Relative of Modern Land Plants
https://vtnews.vt.edu/articles/2020/02/science-billion_year_old_seaweed.html


A photo of a green seaweed fossil dating back 1 billion years. The image was captured using a microscope as the fossil itself is 2 millimeters long, roughly the size of a flea. The dark color of this fossil was created by adding a drop of mineral oil to the rock in which it's embedded, to create contrast.

Virginia Tech paleontologists have made a remarkable discovery in China: 1 billion-year-old micro-fossils of green seaweeds that could be related to the ancestor of the earliest land plants and trees that first developed 450 million years ago.

The micro-fossil seaweeds—a form of algae known as Proterocladus antiquus—are barely visible to the naked eyed at 2 millimeters in length, or roughly the size of a typical flea. Professor Shuhai Xiao said the fossils are the oldest green seaweeds ever found. They were imprinted in rock taken from an area of dry land—formerly ocean—near the city of Dalian in the Liaoning Province of northern China. Previously, the earliest convincing fossil record of green seaweeds were found in rock dated at roughly 800 million years old.

Fossils of red seaweed, which are now common on ocean floors, have been dated as far back as 1.047 billion years old.

A one-billion-year-old multicellular chlorophyte, Nature Ecology & Evolution (2020).
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vox_mundi

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Re: Archaeology/Paleontology news
« Reply #241 on: February 25, 2020, 05:36:51 PM »
Human Populations Survived the Toba Volcanic Super-Eruption 74,000 Years Ago
https://phys.org/news/2020-02-human-populations-survived-toba-volcanic.html

In a study published in Nature Communications, researchers from the Max Planck Institute for the Science of Human History's Department of Archaeology, together with international partners, have presented evidence that Middle Palaeolithic tool users were present in India before and after the Toba super-eruption 74,000 years ago. The findings support arguments that Homo sapiens was present in South Asia prior to major waves of human expansion 60,000 years ago, and that populations endured climatic and environmental changes.

The Toba super-eruption was one of the largest volcanic events over the last 2 million years, about 5,000 times larger than Mount St. Helen's eruption in the 1980s. The eruption occurred 74,000 years ago on the island of Sumatra, Indonesia, and was argued to have ushered in a "volcanic winter" lasting six to 10 years, leading to a 1,000 year-long cooling of the Earth's surface. Theories purported that the volcanic eruption would have led to major catastrophes, including the decimation of hominin populations and mammal populations in Asia, and the near extinction of our own species. The few surviving Homo sapiens in Africa were said to have survived by developing sophisticated social, symbolic and economic strategies that enabled them eventually to re-expand and populate Asia 60,000 years ago in a single, rapid wave along the Indian Ocean coastline. ... The current study provides evidence that Homo sapiens were present in Asia earlier than expected and that the Toba super-eruption wasn't as apocalyptic as believed.

... The current study reports on a unique 80,000 year-long stratigraphic record from the Dhaba site in northern India's Middle Son Valley. Stone tools uncovered at Dhaba in association with the timing of the Toba event provide strong evidence that Middle Palaeolithic tool-using populations were present in India prior to and after 74,000 years ago. Professor J.N. Pal, principal investigator from the University of Allahabad in India notes that "Although Toba ash was first identified in the Son Valley back in the 1980s, until now we did not have associated archaeological evidence, so the Dhaba site fills in a major chronological gap."



Open Access:  Human occupation of northern India spans the Toba super-eruption ~74,000 years ago, Nature Communications
https://www.nature.com/articles/s41467-020-14668-4
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kassy

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Re: Archaeology/Paleontology news
« Reply #242 on: February 25, 2020, 07:27:11 PM »
Toba oh Toba.

The so-called Toba bottleneck didn't happen

09 Feb 2018

Chad Yost and colleagues have a long and detailed article in the current Journal of Human Evolution about why the Toba volcanic eruption 74,000 years ago did not drive ancient humans near extinction.

I want to quote the last two paragraphs of this paper, which give a crystal clear discussion, with references, of why there is no evidence for a massive Toba effect on human populations.

4.7. A falsified Toba catastrophe hypothesis
Since the publication of Ambrose (1998), the Toba supereruption and its proposed 6-year-long volcanic winter continues to be cited repeatedly, particularly in introductory paragraphs, as the natural catastrophe that brought humanity to the brink of extinction (human populations reduced to 10,000 individuals). Recent studies have clearly shown that volcanic winter conditions never occurred in East Africa after the eruption (Lane et al., 2013a ; Jackson et al., 2015), and we have shown that there was a very limited vegetation perturbation in the Southern Rift Valley of East Africa after the eruption. Further, we demonstrated the overestimation of SO2 injections in Toba supereruption climate model simulations by one or two orders of magnitude. This overestimation includes the early models of Rampino and Self (1992) that helped to build the volcanic winter model proposed in Ambrose (1998). The hypothesis that Toba triggered the 1000-year GS-20 cold period is also unlikely to be correct given that rapid cooling in the NH actually started a few hundred years before the Toba eruption, not to mention the fact that modeling by Robock et al. (2009) using a 900× Pinatubo SO2 injection failed to initiate NH glaciation.
Numerous genetic analyses have not detected a bottleneck that coincides with the Toba eruption. In fact, if the source population for the OOA expansion suffered a severe bottleneck, there should be a poorer linear fit to the decline of heterozygosity with distance from Africa (Henn et al., 2012). With the advancement of whole genome sequencing, the once elusive 100–50 ka Late Pleistocene human genetic bottleneck is now converging on ∼50 ka (Lippold et al., 2014; Karmin et al., 2015 ; Malaspinas et al., 2016) and is being attributed to an OOA founder effect bottleneck (Mallick et al., 2016) instead of a population reduction bottleneck. Studies focusing on reconstructing population histories are identifying a possible population reducing bottleneck between ∼150 and ∼130 ka (Li and Durbin, 2011 ; Kidd et al., 2012), which coincides with the penultimate ice ace during MIS 6. However, the peak in Ne at ∼150 ka could have also arisen from increased genetic diversity due to population structure involving separation and admixture (Li and Durbin, 2011), which is reasonable to expect during a cooler and drier MIS 6 climate in Africa. The hypothesis that human populations were reduced to 10,000 individuals after the Toba eruption is currently unsupported, as AMH populations were always relatively low, started to decline around 150 ka, and continued to decrease until ∼30 ka (see Discussion above). As paleoenvironmental, archaeological, and genetic research continues to accumulate, it is becoming increasingly hard to find evidence in favor of the Toba catastrophe hypothesis.
There is no question that the Toba eruption was a massive geological event. Investigating this event in earth systems research has always been a valuable idea.

But it has been a massive distraction for archaeologists.

The Toba bottleneck idea came from the initial observation that there might be a coincidence between population expansion times and the Toba eruption, made 20 years ago. But many geneticists (including me) quickly pointed out that the dates of population expansion have little connection to the dates of population contraction, and that effective population size might be orders of magnitude smaller than the actual human population. Even in 20-year-old mitochondrial DNA data, it was clear that a single short bottleneck post-Toba could not account for the pattern of variation found in African populations.

Meanwhile, human populations in the coldest climate zones, like the Neandertals of Europe, never seemed to show any obvious signs of population reduction at the time of the Toba event. Later, it became clear that the archaeological record much closer to Toba, in India and later Sumatra itself, showed no signs of a major interruption caused by the volcano. It also became clear that the aerosols that cool global climate, like sulfur dioxide, did not scale with the volume of rock ejected by the Toba eruption.

Yet this idea remains surprisingly entrenched in the minds of the public and of documentary filmmakers. I’m surprised there hasn’t been a Toba feature movie. Worse, it seems to dominate an unusual degree of attention in the minds of paleoclimatologists, and in their grant applications.

This is such an example of the failure to communicate effectively between geneticists, geologists, and paleoclimatologists about the limits of their data. The “coincidence” of these events from genetics and geology was only a small overlap between enormous confidence limits.

More + link to the paper on:

http://johnhawks.net/weblog/reviews/climate/toba-bottleneck-didnt-happen-2018.html
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oren

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Re: Archaeology/Paleontology news
« Reply #243 on: February 26, 2020, 04:10:44 AM »
Thank you Kassy. Very interesting.

kassy

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Re: Archaeology/Paleontology news
« Reply #244 on: February 29, 2020, 12:21:05 AM »
Anthropogenic seed dispersal: Rethinking the origins of plant domestication

Summary:
Over the past three millennia, selective breeding has dramatically widened the array of plant domestication traits. However, a close look at the archaeobotanical record illustrates a similar suite of linked traits emerging before humans began selectively breeding food crops. A researchers now summarizes all of these early evolutionary responses in plants, arguing that these shared traits evolved in response to human seed-dispersal services.

https://www.sciencedaily.com/releases/2020/02/200227114450.htm
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kassy

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Re: Archaeology/Paleontology news
« Reply #245 on: March 05, 2020, 04:02:30 PM »
How millets sustained Mongolia's empires

Collaborating with archaeologists from the National University of Mongolia and the Institute of Archaeology in Ulaanbaatar, Dr. Wilkin and her colleagues from the MPI SHH sampled portions of teeth and rib bones from 137 previously excavated individuals. The skeletal fragments were brought back to the ancient isotope lab in Jena, Germany, where researchers extracted bone collagen and dental enamel to examine the ratios of stable nitrogen and carbon isotopes within. With these ratios in hand, scientists were able to reconstruct the diets of people who lived, ate, and died hundreds to thousands of years ago.

Researchers tracked the trends in diet through the millennia, creating a "dietscape" which clearly showed significant differences between the diets of Bronze Age peoples and those who lived during the Xiongnu and Mongol Empires. A typical Bronze Age Mongolian diet was based on milk and meat, and was likely supplemented with small amounts of naturally available plants. Later, during the Xiongnu Empire, human populations displayed a larger range of carbon values, showing that some people remained on the diet common in the Bronze Age, but that many others consumed a high amount of millet-based foods. Interestingly, those living near the imperial heartlands appear to have been consuming more millet-based foods than those further afield, which suggests imperial support for agricultural efforts in the more central political regions. The study also shows an increase in grain consumption and increasing dietary diversity through time, leading up to the well-known Mongolian Empire of the Khans.

...

The view that everyone in Mongolian history was a nomadic herder has skewed discussions concerning social development in this part of the world. Dr. Wilkin notes that "setting aside our preconceived ideas of what prehistory looked like and examining the archaeological record with modern scientific approaches is forcing us to rewrite entire sections of humanity's past."

https://www.sciencedaily.com/releases/2020/03/200303113234.htm
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kassy

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Re: Archaeology/Paleontology news
« Reply #246 on: March 07, 2020, 11:40:23 AM »
Researchers find evidence of a cosmic impact that caused destruction of one of the world's earliest human settlements

Before the Taqba Dam impounded the Euphrates River in northern Syria in the 1970s, an archaeological site named Abu Hureyra bore witness to the moment ancient nomadic people first settled down and started cultivating crops. A large mound marks the settlement, which now lies under Lake Assad.

But before the lake formed, archaeologists were able to carefully extract and describe much material, including parts of houses, food and tools—an abundance of evidence that allowed them to identify the transition to agriculture nearly 12,800 years ago. It was one of the most significant events in our Earth's cultural and environmental history.

Abu Hureyra, it turns out, has another story to tell. Found among the cereals and grains and splashed on early building material and animal bones was meltglass, some features of which suggest it was formed at extremely high temperatures—far higher than what humans could achieve at the time—or that could be attributed to fire, lighting or volcanism.

"To help with perspective, such high temperatures would completely melt an automobile in less than a minute," said James Kennett, a UC Santa Barbara emeritus professor of geology. Such intensity, he added, could only have resulted from an extremely violent, high-energy, high-velocity phenomenon, something on the order of a cosmic impact.

...

Abu Hureyra lies at the easternmost sector of what is known as the Younger Dryas Boundary (YDB) strewnfield, which encompasses about 30 other sites in the Americas, Europe and parts of the Middle East. These sites hold evidence of massive burning, including a widespread carbon-rich "black mat" layer that contains millions of nanodiamonds, high concentrations of platinum and tiny metallic spherules formed at very high temperatures. The YDB impact hypothesis has gained more traction in recent years because of many new discoveries, including a very young impact crater beneath the Hiawatha Glacier of the Greenland ice sheet, and high-temperature meltglass and other similar evidence at an archaeological site in Pilauco, located in southern Chile

...

"A single major asteroid impact would not have caused such widely scattered materials like those discovered at Abu Hureyra," Kennett said. "The largest cometary debris clusters are proposed to be capable of causing thousands of airbursts within a span of minutes across one entire hemisphere of Earth. The YDB hypothesis proposed this mechanism to account for the widely dispersed coeval materials across more than 14,000 kilometers of the Northern and Southern Hemispheres. Our Abu Hureyra discoveries strongly support a major impact event from such a fragmented comet."

https://phys.org/news/2020-03-evidence-cosmic-impact-destruction-world.html

https://www.nature.com/articles/s41598-020-60867-w
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TerryM

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Re: Archaeology/Paleontology news
« Reply #247 on: March 07, 2020, 07:22:25 PM »
^^
The evidence in favor of the Black Mat Event continues to grow.
Welcome news to those of us that saw what we considered to be incontrovertible evidence at Murray Spring & other sites in the American deserts.


As more of the archeological, geological and paleontological communities converge in their understanding of this event textbooks will need to be rewritten and various theories of punctured equilibrium may find new adherents. Will iridium spikes and magnetic spherules now be tested for whenever sites close to that date are worked?


It's interesting that evidence is being found so far away from Greenland and the Americas. How many cultures, and how many species were decimated or annihilated?
Terry

kassy

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Re: Archaeology/Paleontology news
« Reply #248 on: March 10, 2020, 12:36:36 PM »
This is pretty awesome:

Ancient shell shows days were half-hour shorter 70 million years ago

Earth turned faster at the end of the time of the dinosaurs than it does today, rotating 372 times a year, compared to the current 365, according to a new study of fossil mollusk shells from the late Cretaceous. The new measurement informs models of how the Moon formed and how close to Earth it has been over the 4.5-billion-year history of the Earth-Moon gravitational dance.

...

The high resolution obtained in the new study combined with the fast growth rate of the ancient bivalves revealed unprecedented detail about how the animal lived and the water conditions it grew in, down to a fraction of a day.

"We have about four to five datapoints per day, and this is something that you almost never get in geological history. We can basically look at a day 70 million years ago. It's pretty amazing," said Niels de Winter, an analytical geochemist at Vrije Universiteit Brussel and the lead author of the new study.

...

Chemical analysis of the shell indicates ocean temperatures were warmer in the Late Cretaceous than previously appreciated, reaching 40 degrees Celsius (104 degrees Fahrenheit) in summer and exceeding 30 degrees Celsius (86 degrees Fahrenheit) in winter. The summer high temperatures likely approached the physiological limits for mollusks, de Winter said.

...

The new method focused a laser on small bits of shell, making holes 10 micrometers in diameter, or about as wide as a red blood cell. Trace elements in these tiny samples reveal information about the temperature and chemistry of the water at the time the shell formed. The analysis provided accurate measurements of the width and number of daily growth rings as well as seasonal patterns. The researchers used seasonal variations in the fossilized shell to identify years.

The new study found the composition of the shell changed more over the course of a day than over seasons, or with the cycles of ocean tides. The fine-scale resolution of the daily layers shows the shell grew much faster during the day than at night

"This bivalve had a very strong dependence on this daily cycle, which suggests that it had photosymbionts," de Winter said. "You have the day-night rhythm of the light being recorded in the shell."

...

De Winter's careful count of the number of daily layers found 372 for each yearly interval. This was not a surprise, because scientists know days were shorter in the past. The result is, however, the most accurate now available for the late Cretaceous, and has a surprising application to modeling the evolution of the Earth-Moon system.

....

Because in the history of the Moon, 70 million years is a blink in time, de Winter and his colleagues hope to apply their new method to older fossils and catch snapshots of days even deeper in time.

https://www.sciencedaily.com/releases/2020/03/200309135410.htm
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oren

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Re: Archaeology/Paleontology news
« Reply #249 on: March 10, 2020, 06:45:01 PM »
Amazing and interdisciplinary.
Science at its finest.