Archaeology – Page 6 – artdiamondblog.com

Dinosaur Belches and Farts Made More Global Warming Gas than All of Today’s Sources

(p. A6) Gassy dinosaurs may have spewed so much methane into the air that it could have helped warm the climate tens of millions of years ago, when temperatures were much higher than today, a team of U.K. scientists reported Monday.
The stomach gas released each year by a group of long-necked, plant-eating dinosaurs, which included the world’s largest known land animals, may have equaled the total amount of methane produced every year today from all natural, agricultural and industrial sources, the researchers said Monday in the journal Current Biology. Methane, a greenhouse gas, is 23 times as effective at trapping heat in the atmosphere as carbon dioxide.
The new scientific work highlights the importance of wildlife, livestock and other natural sources of greenhouse-gas emissions in shaping the global climate.
As with cows, sheep and buffalo today, these plant-eating dinosaurs, known as sauropods, likely digested their leafy greens with the help of methane-producing microbes in their stomachs that fermented the plant matter after it was chewed and swallowed. Generally, other plant eaters and creatures that eat meat, including people, don’t digest their food this way and pass gas that is mostly nitrogen and carbon dioxide, with traces of methane and hydrogen.
Cattle belching and gas account for about 20% of U.S. methane emissions, according to the Environmental Protection Agency.

For the full story, see:
ROBERT LEE HOTZ. “Dinosaur Gas Emissions May Have Warmed Air.” The Wall Street Journal (Tues., May 8, 2012): A6.
(Note: online version of the story is dated May 7, 2012.)

The academic article on sauropod methane emissions is:
Wilkinson, David M., Euan G. Nisbet, and Graeme D. Ruxton. “Could Methane Produced by Sauropod Dinosaurs Have Helped Drive Mesozoic Climate Warmth?” Current Biology 22, no. 9 (May 8, 2012): R292-R93.

The Tasmanian Technological Regress: “Slow Strangulation of the Mind”

(p. 78) The most striking case of technological regress is Tasmania. Isolated on an island at the end of the world, a population of less than 5,000 hunter-gatherers divided into nine tribes did not just stagnate, or fail to progress. They fell steadily and gradually back into a simpler toolkit and lifestyle, purely because they lacked the numbers to sustain their existing technology. Human beings reached Tasmania at least 35,000 years ago while it was still connected to Australia. It remained connected – on and off – until about 10,000 years ago, when the rising seas filled the Bass Strait. Thereafter the Tasmanians were isolated. By the time Europeans first encountered Tasmanian natives, they found them not only to lack many of the skills and tools of their mainland cousins, but to lack many technologies that their own ancestors had once possessed. They had no bone tools of any kind, such as needles and awls, no cold-weather clothing, no fish hooks, no hafted tools, no barbed spears, no fish traps, no spear throwers, no boomerangs. A few of these had been invented on the mainland after the Tasmanians had been isolated from it – the boomerang, for instance – but most had been made and used by the very first Tasmanians. Steadily and inexorably, so the archaeological history tells, these tools and tricks were abandoned. Bone tools, for example, grew simpler and simpler until they were dropped altogether about 3,800 years ago. Without bone tools it became impossible to sew skins into clothes, so even in the bitter winter, the Tasmanians went nearly naked but for seal-fat grease smeared on their skin and wallaby pelts over their shoulders. The first Tasmanians caught and ate plenty of fish, but by the time of Western contact they not only ate no fish (p. 79) and had eaten none for 3,000 years, but they were disgusted to be offered it (though they happily ate shellfish).
The story is not quite that simple, because the Tasmanians did invent a few new things during their isolation. Around 4,000 years ago they came up with a horribly unreliable form of canoe-raft, made of bundles of rushes and either paddled by men or pushed by swimming women (!), which enabled them to reach offshore islets to harvest birds and seals. The raft would become waterlogged and disintegrate or sink after a few hours, so it was no good for re-establishing contact with the mainland. As far as innovation goes, it was so unsatisfactory that it almost counts as an exception to prove the rule. The women also learnt to dive up to twelve feet below the water to prise clams off the rocks with wooden wedges and to grab lobsters. This was dangerous and exhausting work, which they were very skilled at: the men did not take part. So it was not that there was no innovation; it was that regress overwhelmed progress.
The archaeologist who first described the Tasmanian regress, Rhys Jones, called it a case of the ‘slow strangulation of the mind’, which perhaps understandably enraged some of his academic colleagues. There was nothing wrong with individual Tasmanian brains; there was something wrong with their collective brains. Isolation – self-sufficiency – caused the shrivelling of their technology. Earlier I wrote that division of labour was made possible by technology. But it is more interesting than that. Technology was made possible by division of labour: market exchange calls forth innovation.

Source:
Ridley, Matt. The Rational Optimist: How Prosperity Evolves. New York: Harper, 2010.

First Human Tools 1.76 Million Years Ago

“A study dates human tools like this ax to 1.76 million years ago.”

(p. A8) A new geological study, being reported Thursday in the journal Nature, showed that tools from a site near Lake Turkana in Kenya were made about 1.76 million years ago, the earliest of their ilk found so far. Previous dates were estimates ranging from 1.4 million to 1.6 million years ago.

Although no erectus fossils were found with the Turkana tools, a skull of that species was excavated last year in the same sediment level across the lake. This suggests that Homo erectus was responsible for these particular tools, which were made with what scientists refer to as Acheulean technology. The term connotes the type of oval and pear-shaped hand axes and other implements that were a specialty of early humans.

For the full story, see:
JOHN NOBLE WILFORD. “Earliest Signs of Advanced Tools Found.” The New York Times (Thurs., September 1, 2011): A8.
(Note: ellipsis added.)
(Note: the online version of the article was dated August 31, 2011.)

Paleolithic Homo Sapiens Engaged in Long Distance Trade

(p. 71) At Mezherich, in what is now Ukraine, 18,000 years ago, jewellery made of shells from the Black Sea and amber from the Baltic implied trade over hundreds of miles.
This is in striking contrast to the Neanderthals, whose stone tools were virtually always made from raw material available within an hour’s walk of where the tool was used.

Source:
Ridley, Matt. The Rational Optimist: How Prosperity Evolves. New York: Harper, 2010.

Hunter-Gatherers Suffered Violence, Famine and Disease–No Idyllic Golden Age

(p. 44) The warfare death rate of 0.5 per cent of the population per year that was typical of many hunter-gatherer societies would equate to two billion people dying during the twentieth century (instead of 100 million). At a cemetery uncovered at Jebel Sahaba, in Egypt, dating from 14,000 years ago, twenty-four of the fifty-nine bodies had died from unhealed wounds caused by spears, darts and arrows. Forty of these bodies were women or children. Women and children generally do not take part in warfare – but they are (p. 45) frequently the object of the fighting. To be abducted as a sexual prize and see your children killed was almost certainly not a rare female fate in hunter-gatherer society. After Jebel Sahaba, forget the Garden of Eden; think Mad Max.
It was not just warfare that limited population growth. Hunter-gatherers are often vulnerable to famines. Even when food is abundant, it might take so much travelling and trouble to collect enough food that women would not maintain a sufficient surplus to keep themselves fully fertile for more than a few prime years. Infanticide was a common resort in bad times. Nor was disease ever far away: gangrene, tetanus and many kinds of parasite would have been big killers. Did I mention slavery? Common in the Pacific north-west. Wife beating? Routine in Tierra del Fuego. The lack of soap, hot water, bread, books, films, metal, paper, cloth? When you meet one of those people who go so far as to say they would rather have lived in some supposedly more delightful past age, just remind them of the toilet facilities of the Pleistocene, the transport options of Roman emperors or the lice of Versailles.

Source:
Ridley, Matt. The Rational Optimist: How Prosperity Evolves. New York: Harper, 2010.

“Just What Ailments Are Pylos Tablets Supposed to Alleviate?”

“Professor Bennett’s work opened a window to deciphering tablets written in Linear B, a Bronze Age Aegean script.” Source of caption and photo: online version of the NYT obituary quoted and cited below.

(p. 22) Deciphering an ancient script is like cracking a secret code from the past, and the unraveling of Linear B is widely considered one of the most challenging archaeological decipherments of all time, if not the most challenging.
. . .
Linear B recorded the administrative workings of Mycenaean palatial centers on Crete and the Greek mainland 3,000 years ago: accounts of crops harvested, flocks tended, goods manufactured (including furniture, chariots and perfume), preparations for religious feasts and preparations for war.
It was deciphered at last in 1952, not by a scholar but by an obsessed amateur, a young English architect named Michael Ventris. The decipherment made him world famous before his death in an automobile accident in 1956.
As Mr. Ventris had acknowledged, he was deeply guided by Professor Bennett’s work, which helped impose much-needed order on the roiling mass of strange, ancient symbols.
In his seminal monograph “The Pylos Tablets” (1951), Professor Bennett published the first definitive list of the signs of Linear B. Compiling such a list is the essential first step in deciphering any unknown script, and it is no mean feat.
. . .
“We know how much Ventris admired Bennett, because he immediately adopted Bennett’s sign list of Linear B for his own work before the decipherment,” said Mr. Robinson, whose book “The Man Who Deciphered Linear B” (2002) is a biography of Mr. Ventris. “He openly said, ‘This is a wonderful piece of work.’ ”
. . .
As meticulous as Professor Bennett’s work was, it once engendered great confusion. In 1951, after he sent Mr. Ventris a copy of his monograph, a grateful Ventris went to the post office to pick it up. As Mr. Robinson’s biography recounts, a suspicious official, eyeing the package, asked him: “I see the contents are listed as Pylos Tablets. Now, just what ailments are pylos tablets supposed to alleviate?”

For the full obituary, see:
MARGALIT FOX. “Emmett L. Bennett Jr., Ancient Script Expert, Dies at 93.” The New York Times, First Section (Sun., January 1, 2012,): 22.
(Note: ellipses added.)
(Note: the online version of the obituary is dated December 31, 2011, and has the title: “Emmett L. Bennett Jr., Expert on Ancient Script, Dies at 93.”)

The book on the amateur, uncredentialed Ventris is:
Robinson, Andrew. The Man Who Deciphered Linear B: The Story of Michael Ventris. London, UK: Thames & Hudson, 2002.

“Emmett L. Bennett Jr.” Source of caption and photo: online version of the NYT obituary quoted and cited above.

Newly Found Fossils Indicate Life Evolved Soon After the Late Heavy Bombardment

“A collection of tubular microfossils found in 3.4-billion-year-old sandstone from Western Australia.” Source of caption and photo: online version of the NYT article quoted and cited below.

(p. A1) A team of Australian and British geologists have discovered fossilized, single-cell organisms that are 3.4 billion years old and that the scientists say are the oldest known fossils on earth.

Their assertion, if sustained, confirms the view that life evolved on earth surprisingly soon after the Late Heavy Bombardment, a reign of destruction in which waves of asteroids slammed into the primitive planet, heating the surface to molten rock and boiling the oceans into an incandescent mist. The bombardment, which ended around 3.85 billion years ago, would have sterilized the earth’s surface of any incipient life.
The claim is also a new volley in a long-running conflict over who has found the oldest fossil.
The new microfossils are described in Sunday’s issue of Nature Geoscience by a team led by David Wacey of the University of Western Australia and Martin D. Brasier of the University of Oxford. The fossils were found in sandstone at the base of the Strelley Pool rock formation in Western Australia.
The sandstone, 3.4 billion years ago, was a beach on one of the few islands that had started to (p. A3) appear above the ocean’s surface. Conditions were very different from those of today. The moon orbited far closer to earth, raising huge tides. The atmosphere was full of methane, since plants had not yet evolved to provide oxygen, and greenhouse warming from the methane had heated the oceans to the temperature of a hot bath.
It was in these conditions, the geologists believe, that organisms resembling today’s bacteria lived in the crevices between the pebbles on the beach. Examining thin slices of rock under the microscope, they have found structures that look like living cells, some in clusters that seem to show cell division.
Cell-like structures in ancient rocks can be deceiving — many have turned out to be artifacts formed by nonbiological processes. In this case, the geologists have gathered considerable circumstantial evidence that the structures they see are biological. With an advanced new technique, they have analyzed the composition of very small spots within the cell-like structures. “We can see carbon, sulfur, nitrogen and phosphorus, all within the cell walls,” Dr. Brasier said.

For the full story, see:
NICHOLAS WADE. “Team Claims It Has Found Oldest Fossils.” The New York Times (Mon., August 22, 2011): A1 & A3.
(Note: the online version of the article has the date August 21, 2011.)

In State of Nature 15% of People Died Violently

Source of graph: online version of the WSJ article quoted and cited below.

(p. C1) For centuries, social theorists like Hobbes and Rousseau speculated from their armchairs about what life was like in a “state of nature.” Nowadays we can do better. Forensic archeology–a kind of “CSI: Paleolithic”–can estimate rates of violence from the proportion of skeletons in ancient sites with bashed-in skulls, decapitations or arrowheads embedded in bones. And ethnographers can tally the causes of death in tribal peoples that have recently lived outside of state control.

These investigations show that, on average, about 15% of people in prestate eras died violently, compared to about 3% of the citizens of the earliest states. Tribal violence commonly subsides when a state or empire imposes control over a territory, leading to the various “paxes” (Romana, Islamica, Brittanica and so on) that are familiar to readers of history.
It’s not that the first kings had a benevolent interest in the welfare of their citizens. Just as a farmer tries to prevent his livestock from killing one another, so a ruler will try to keep his subjects from cycles of raiding and feuding. From his point of view, such squabbling is a dead loss–forgone opportunities to extract taxes, tributes, soldiers and slaves.
. . .
(p. C2) We see evidence of the pacifying effects of government in the way that rates of killing declined following the expansion and consolidation of states in tribal societies and in medieval Europe. And we can watch the movie in reverse when violence erupts in zones of anarchy, such as the Wild West, failed states and neighborhoods controlled by mafias and street gangs, who can’t call 911 or file a lawsuit to resolve their disputes but have to administer their own rough justice.
Another pacifying force has been commerce, a game in which everybody can win. As technological progress allows the exchange of goods and ideas over longer distances and among larger groups of trading partners, other people become more valuable alive than dead. They switch from being targets of demonization and dehumanization to potential partners in reciprocal altruism.
For example, though the relationship today between America and China is far from warm, we are unlikely to declare war on them or vice versa. Morality aside, they make too much of our stuff, and we owe them too much money.
A third peacemaker has been cosmopolitanism–the expansion of people’s parochial little worlds through literacy, mobility, education, science, history, journalism and mass media. These forms of virtual reality can prompt people to take the perspective of people unlike themselves and to expand their circle of sympathy to embrace them.

For the full essay, see:
STEVEN PINKER. “Violence Vanquished; We believe our world is riddled with terror and war, but we may be living in the most peaceable era in human existence. Why brutality is declining and empathy is on the rise.” The New York Times (Weds., SEPTEMBER 24, 2011): C1-C2.
(Note: ellipsis added.)

The article quoted was adapted by Pinker from his book:
Pinker, Steven. The Better Angels of Our Nature: Why Violence Has Declined. New York: Viking Press, 2011.

Source of graph: online version of the WSJ article quoted and cited above.

Evidence “of Complex Human Cognition” 100,000 Years Ago

“Deposits of 100,000-year-old ocher were found in a shell alongside tools for pounding and grinding paint materials.” Source of caption and photo: online version of the NYT article quoted and cited below.

(p. A12) Digging deeper in a South African cave that had already yielded surprises from the Middle Stone Age, archaeologists have uncovered a 100,000-year-old workshop holding the tools and ingredients with which early modern humans apparently mixed some of the first known paint.

These cave artisans had stones for pounding and grinding colorful dirt enriched with a kind of iron oxide to a powder, known as ocher. This was blended with the binding fat of mammal-bone marrow and a dash of charcoal. Traces of ocher were left on the tools, and samples of the reddish compound were collected in large abalone shells, where the paint was liquefied, stirred and scooped out with a bone spatula.
Archaeologists said that in the workshop remains they were seeing the earliest example yet of how emergent Homo sapiens processed ocher, one of the species’ first pigments in wide use, its red color apparently rich in symbolic significance. The early humans may have applied the concoction to their skin for protection or simply decoration, experts suggested. Perhaps it was their way of making social and artistic statements on their bodies or their artifacts.
Of special importance to the scientists who made the discovery, the ocher workshop showed that early humans, whose anatomy was modern, had also begun thinking like us. In a report published online on Thursday in the journal Science, the researchers called this evidence of early conceptual abilities “a benchmark in the evolution of complex human cognition.”
The discovery dials back the date when the modern Homo sapiens population was known to have started using paint. Previously, no workshop older than 60,000 years had come to light, and the earliest cave and rock art began appearing about 40,000 years ago. The exuberant flowering among the Cro-Magnon artists in the caves of Europe would come even later; the parade of animals on the walls of Lascaux in France, for example, was executed 17,000 years ago.
. . .
Alison S. Brooks, an archaeologist at George Washington University who studies the Middle Stone Age in Africa but was not involved in this research, said, “This is another spectacular discovery from Blombos.”

For the full story, see:
JOHN NOBLE WILFORD. “In African Cave, Ancient Paint Factory Pushes Human Symbolic Thought ‘Far Back’.” The New York Times (Fri., October 14, 2011): A12.
(Note: ellipsis added.)
(Note: the online version of the article has the date October 13, 2011 and the title “In African Cave, Signs of an Ancient Paint Factory.”)

Fossil Shows Placental Mammals 35 Million Years Earlier

“The earliest known eutherian from the Jurassic of China.” Source of caption and photo: online version of the NYT article quoted and cited below.

(p. D3) The split between placental mammals and marsupials may have occurred 35 million years earlier than previously thought, according to a new study.
. . .
The newly identified mammal was small, weighing less than a chipmunk. Based on its claws, it appears to have been an active climber. “This was a skinny little animal, eating insects,” said Dr. Luo. “We imagine it was active in the night and capable of going up and down trees.”
Its discovery helps reconcile fossil evidence and molecular analysis. Modern molecular studies, which use DNA to estimate dates of evolution, also put the emergence of placentals at about 160 million years ago.

For the full story, see:
SINDYA N. BHANOO. “OBSERVATORY; A Small Mammal Fossil Tells a Jurassic Tale.” The New York Times (Tues., August 30, 2011): D3.
(Note: ellipsis added.)
(Note: the online version of the article is dated August 24 (sic), 2011.)