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Category Archives: technology

Echoes from the past (May-9-2013)

I am getting updated with a rather long backlog, so I will speed things up placing here in nearly telegraphic style the informative snippets that require less work. This does not mean that they are less interesting, not at all, just that I have to adapt to that elusive quality of time…

Middle Paleolithic

Toba supervolcano only had short-term climate effectBBC.
Research on Lake Malawi’s sediments shows that the climate-change effect of the catastrophic eruption was limited. Droughts previously believed to be from that period have been revised to be from at least 10,000 years before, corresponding to the end of the Abbassia Pluvial rather than to Toba super-eruption.

Upper Paleolithic

Altai rock art and early astronomy from 16,000 BPSiberian Times, Daily Mail.
Sunduki (Khakassia), here there are what are surely the oldest rock art of Northern Asia, representing people hunting or interacting among them, which are from just centuries ago, however other petroglyphs are apparently much older like this horse:

Prof. Vitaly Larichev (Institute of Archeology and Ethnography, Russian Academy of Sciences) has detected a whole astronomical structure implemented in the landscape.

He claims to have found ‘numerous ancient solar and lunar observatories around Sunduki’.

‘This square pattern of stones on the ground shows you the place’, he
told visiting author Kira Van Deusen. ‘I knew there would be an
orientation point, but we had to search through the grass for a long
time to find it.

‘Now look up to the top of that ridge. You see a place where there is
a crack between the rocks? If you were here on the summer solstice, you
would see the sun rise right there. Or you would if you were here 2,000
years so. Now the timing is slightly differen’.



High on one cliff wall is a rock engraving showing dragon heads in one direction, and snake heads in the other.

‘If the sun were shining, we could tell the time,’ he said. ‘In the
morning the shadow moves along the snake’s body from his head to his
tail, and in the afternoon it comes from the other direction along the
dragon.

‘From the same observation point you can determine true north and south by sighting along the mountains’.

Neolithic

Vietnam: early cemetery dug in Thahn HoaAustralian National University.
Some 140 human remains of all ages have been unearthed at the site of Con Co Ngua, estimated to be 6-4000 years old. Cemeteries of this size and age were previously unknown in the region. The site has also revealed a dearth of artifacts. 
The people were buried in fetal position with meat cuts of buffalo or deer.

Chalcolithic

India: 4000 y.o. stone tools unearthed in Bhopal (Madhya Pradesh, Narmada river)India Today.
Details:
  • Some of them are decorated with aquatic animals.
  • 150×200 m. mound in Birjakhedi
  • Terracotta game pieces
  • Pottery (incl. jars, pots, dishes)
  • Stone and ivory beads
Bell Beaker rich lady’s burial unearthed in Berkshire (England)Wessex Archaeology.
The middle-aged woman wore a necklace of tubular golden beads, amber buttons on her clothes and a possible lignite bracelet. She was accompanied by a bell-shaped beaker of the “corded” type (oldest and roughest variant, of likely Central European inception).
The chemical signature of the gold beads is coherent with deposits from Southern Britain and SE Ireland. 

Giza pyramid construction’s logistics revealed Live Science.


Caesar beat the Gauls.
Was there not even a cook in his army?

Bertolt Brecht (A Worker reads History)

Now we know that at the very least the famed early pharaohs Khafra, Khufu and Menkaure, who ordered the massive pyramids of Giza to be built as their tombs did have some cooks in charge of feeding the many workers who actually built them, stone by stone. 
These workers were housed in a village some 400 meters south of the Sphinx, known as Heit el-Ghurab. In this place archaeologists have found a cemetery, a corral with apparent slaughter areas and piles of animal bones. Based on these, researchers estimate that more than 2,000 kilograms of meat were eaten every day during the construction of Menkaure’s pyramid, the last and smallest one of the three geometric mounds. 
The figures estimated for such a logistic operation border disbelief: 22,000 cows, 55,000 sheep and goats, 1200 km² of grazing land (roughly the size of Los Angeles or 5% of the Nile Delta), some 3500 herders (adding up to almost 20,000 people if we include their families). 
A curious detail is that most of the beef was destined to the building of the overseers, while the common workers were mostly fed sheep or goat instead. Another settlement to the East of apparently local farmers ate most of the pork. There were also temporary tent camps closer to the pyramids.

Iron Age

Late Indus Valley Civilization was overcome by violenceNational Geographic.

Harappa (CC by Shephali11011)
The Late Indus Valley Civilization (Cemetery H cultural layer, usually attributed to the Indoeuropean invasions) was, unlike in previous periods, quite violent, new evidence highlights. 
The evidence from the bones also highlights the arrival of many non-local men, who apparently married local women. But the most shocking element is the striking evidence of widespread violence:

The skull of a child between four and six years old was
cracked and crushed by blows from a club-like weapon. An adult woman was
beaten so badly—with extreme force, according to researchers—that her
skull caved in. A middle-aged man had a broken nose as well as damage
to his forehead inflicted by a sharp-edged, heavy implement.
Of the 18 skulls examined from this time period, nearly half showed serious injuries from violence …

Gaming pieces of Melton Mowbray (England)Science Daily.

Excavation of a hillfort at Burrough Hill revealed ancient gaming pieces, among other materials. 

Funerary chamber found near the original location of the Lady of Baza (Andalusia)Paleorama[es].

(CC by P.A. Salguero Quiles)
The tomb has an access gate and is estimated to be from the 5th or 4th centuries BCE (Iberian culture) and, unlike most burials of the time, the corpse was not incinerated. 
The finding highlights the need for further archaeological work in all the hill but the severe budgetary cuts threaten this development. 
Baza (Granada) hosts a dedicated archaeological museum inaugurated in 2011. 

Tocharian mummy buried with marijuana hoardPaleorama[es].

Some 800 grams of the psychedelic plant, including seeds, were found at the burial place of a Tocharian man, presumably a shaman, at Yanghai (Uyghuristan), belonging to the Gushi culture and dated to at least 2700 years ago. The plant belongs to a cultivated variety.
Some of the oldest cannabis evidence are also from that area (Pazyrk culture c. 2500 years ago) and also from Nepal (Mustang, similar dates). Later in Southern Central Asia it was used in combination with opium and ephedra, from where soon migrated to South Asia and many other parts of Eurasia.

Genetics

New device radically reduces costs and time in DNA extractionScience Daily.
Researchers from the University of Washington and NanoFacture Inc. have developed a device, which looks like a kitchen appliance, able to extract DNA from tissues (like saliva or blood) in minutes at low cost and without using the toxic chemicals habitual in the field.
The prototype is designed for four samples but can be scaled for the lab standard of 96 samples at once.

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Bisphenol A severely disrupts fetal epigenetics

Water bottle containing bisphenol A
The most controversial chemical compound bisphenol A is found in many plastics, including sometimes those used as food or water containers. This study adds to the long list of known harms of this chemical, which nevertheless remains widely allowed.
Martha Susiarjo et al., Bisphenol A Exposure Disrupts Genomic Imprinting in the Mouse. PLoS Genetics 2013. Open accessLINK [doi:10.1371/journal.pgen.1003401]
Abstract

Exposure to endocrine disruptors is associated with developmental defects. One compound of concern, to which humans are widely exposed, is bisphenol A (BPA). In model organisms, BPA exposure is linked to metabolic disorders, infertility, cancer, and behavior anomalies. Recently, BPA exposure has been linked to DNA methylation changes, indicating that epigenetic mechanisms may be relevant. We investigated effects of exposure on genomic imprinting in the mouse as imprinted genes are regulated by differential DNA methylation and aberrant imprinting disrupts fetal, placental, and postnatal development. Through allele-specific and quantitative real-time PCR analysis, we demonstrated that maternal BPA exposure during late stages of oocyte development and early stages of embryonic development significantly disrupted imprinted gene expression in embryonic day (E) 9.5 and 12.5 embryos and placentas. The affected genes included Snrpn, Ube3a, Igf2, Kcnq1ot1, Cdkn1c, and Ascl2; mutations and aberrant regulation of these genes are associated with imprinting disorders in humans. Furthermore, the majority of affected genes were expressed abnormally in the placenta. DNA methylation studies showed that BPA exposure significantly altered the methylation levels of differentially methylated regions (DMRs) including the Snrpn imprinting control region (ICR) and Igf2 DMR1. Moreover, exposure significantly reduced genome-wide methylation levels in the placenta, but not the embryo. Histological and immunohistochemical examinations revealed that these epigenetic defects were associated with abnormal placental development. In contrast to this early exposure paradigm, exposure outside of the epigenetic reprogramming window did not cause significant imprinting perturbations. Our data suggest that early exposure to common environmental compounds has the potential to disrupt fetal and postnatal health through epigenetic changes in the embryo and abnormal development of the placenta.
 

Hafting with bitumen in Neanderthal Romania

Julien Riel-Salvatore mentions today in his blog that another instance of Neanderthal hafting has been discovered, this time in Romania (Râşnov Cave), dated to 33.3-28.9 Ka. BP (uncalibrated) and with Mousterian technology (generally associated with Neanderthals).
A previous case was known to exist in Palestine (Umm el Tlel, c. 40-70 Ka BP). Findings of birch pitch tar, also used for hafting, are even older: 125 Ka in Germany and maybe even older in Italy, evidencing the use of different technical solutions for the same problem.
I refer to A Very Remote Period Indeed for the papers and further details. 
Reconstructed Mousterian spear (source)
 
 

Modeling cultural diversity, local extinctions, etc.

Before I forget, just a quick mention of another potentially interesting paper published at PLoS ONE this week:


L.S. Premo and S.L. Kuhn, Modeling Effects of Local Extinctions on Culture Change and Diversity in the Paleolithic. PLoS ONE 2010. Open access.

Abstract
The persistence of early stone tool technologies has puzzled archaeologists for decades. Cognitively based explanations, which presume either lack of ability to innovate or extreme conformism, do not account for the totality of the empirical patterns. Following recent research, this study explores the effects of demographic factors on rates of culture change and diversification. We investigate whether the appearance of stability in early Paleolithic technologies could result from frequent extinctions of local subpopulations within a persistent metapopulation. A spatially explicit agent-based model was constructed to test the influence of local extinction rate on three general cultural patterns that archaeologists might observe in the material record: total diversity, differentiation among spatially defined groups, and the rate of cumulative change. The model shows that diversity, differentiation, and the rate of cumulative cultural change would be strongly affected by local extinction rates, in some cases mimicking the results of conformist cultural transmission. The results have implications for understanding spatial and temporal patterning in ancient material culture.

This mention is not adhesion. I find the modeling potentially interesting in its essentials but I surely have many discrepancies on issues such as assuming tiny “populations” of some 25 individuals in black and white (life or death) states. Such size is ok with operative hunter-gatherer bands but these are not “sovereign” units but just dynamic and fluctuating economic ones, integrated in larger groups. Probably a better size would be something like 100 or 200 people but again integrated into larger units of several hundreds to several thousands (tribes or nations).

Also we have to consider that people change “clans”, for example when marrying. So cultural, as well genetic flow is persistent at least within the borders of the ethnicity, which are anyhow generally open. So I guess that the modeling needs a lot of refinement but still it is a curious speculation – or exploration if you wish.

Something I do agree is in the authors founding their research on previous works that strongly suggest that population size and specially connectivity is critical in driving and maintaining the rhythm of innovation.

 
 

The Antikythera mechanism: astonishing ancient technical and astronomical science

I do not often write on such recent historical matters but this case is really fascinating, involving not just history and archaeology but also astronomy and sophisticated mechanics that anticipate modern computers.

Jo Marchant, Ancient astronomy: Mechanical inspiration. Nature News, 2010. Open access (article).
See also: GrrlScientist’s article at Punctuated Equilibrium blog at The Guardian: The Antikythera Mechanism. This is what I want for Christmas! 
This last article (found via Archaeology in Europe), features a fancy video of a Lego reconstruction of the mechanism (which is pretty curious indeed) but more interesting are maybe the following two videos from Nature YouTube channel:
It is lovely, I understand, to see how these ancient peoples had such a complex understanding of Astronomy, being able to predict eclipses with high detail. But maybe even more fascinating is that they were already building elaborate clock mechanisms for that purpose, devices not known to have existed otherwise until the eve of Modern Age. 
In the last video it is suggested that the astro-clock could have been invented by Archimedes of Syracuse, whom we know was the most celebrated scientific genius of Antiquity. The geography suggested by the mechanism is one of the Ionian Sea, not the Aegean or the East Mediterranean, however the date is from a century after Archimedes died. Yet they ponder if there could have been an Archimedean school in Syracuse for some time, which was in fact producing these technological marvels, whose knowledge was later lost. 
It is also impressive to realize how technology may be lost, maybe because of lack of demand or socio-cultural drive. Ancient Greeks also knew of other marvels such as rudimentary steam engines, which never had much of an impact in that society overall – yet they would change everything two millennia later.