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Category Archives: sea

Northern Marianas was first colonized from Philippines

Lapita pot from Tonga (source)
The first known colonists of Tinian (Northern Marianas) were people coming from Luzon and using a kind of red painted pottery which is also found in Northern Luzon, Philippines, similar to  Lapita (Island Melanesia, Polynesia).
However these people seem to have arrived to the Marianas a century or two before the Lapita carriers (precursors of Oceanic languages) reached Melanesia, according to Peter Bellwood.
Source and more details: Islands Business (interview with Bellwood), via Pileta.
See also:
 
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Posted by on February 28, 2013 in archaeology, Neolithic, Oceania, sea

 

Atlantic thermohaline currents nearly stopped in some cold spells of the Ice Age

That is what researchers claim in a new study:
Stephan P. Ritz et al., Estimated strength of the Atlantic overturning circulation during the last deglaciation. Nature Geoscience 2013. Pay per viewLINK [doi:10.1038/ngeo1723]

Abstract


The Atlantic meridional overturning circulation affects the latitudinal distribution of heat, and is a key component of the climate system. Proxy reconstructions, based on sedimentary 231Pa/230Th ratios and the difference between surface- and deep-water radiocarbon ages, indicate that during the last glacial period, the overturning circulation was reduced during millennial-scale periods of cooling. However, much debate exists over the robustness of these proxies. Here we combine proxy reconstructions of sea surface and air temperatures and a global climate model to quantitatively estimate changes in the strength of the Atlantic meridional overturning circulation during the last glacial period. We find that, relative to the Last Glacial Maximum, the overturning circulation was reduced by approximately 14 Sv during the cold Heinrich event 1. During the Younger Dryas cold event, the overturning circulation was reduced by approximately 12 Sv, relative to the preceding warm interval. These changes are consistent with qualitative estimates of the overturning circulation from sedimentary 231Pa/230Th ratios. In addition, we find that the strength of the overturning circulation during the Last Glacial Maximum and the Holocene epoch are indistinguishable within the uncertainty of the reconstruction.

Summary of thermohaline circulation (public domain, NASA)
In the North Atlantic the best known thermohaline current is the Gulf Stream, which effectively keeps Europe several degrees warmer than it would be otherwise, allowing a relatively dense population at latitudes unheard of elsewhere on Earth. This current was weak at best in the Ice Age. 
Notice that they say that they can find any difference between present day (Holocene epoch) and the Last Glacial Maximum, so it cannot be inferred, it seems, that the glaciation itself had anything to do with the thermohaline currents but only with  some particular cold spells of the late Upper Pleistocene, particularly the HE1 (c. 18-14.6 Ka ago) and the Younger Dryas (c. 10 Ka ago).
 
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Posted by on February 11, 2013 in climate, Epipaleolithic, Ice Age, Magdalenian, sea

 

Whale remains reinforce the notion of Magdalenian being linked to sea mammal predation

First it was the whale bone spear point of Isturitz (Basque Country), then the isotope evidence of sea mammal based diet of a Magdalenian individual from Kendric Cave (Wales) and now direct evidence of whale remains in the cave of Nerja (Andalusia). The evidence mounts up for a quasi-Inuit lifestyle of at least some people of the Magdalenian culture of late Upper Paleolithic Europe.
Esteban Álvarez Fernández et al., Occurrence of whale barnacles in Nerja Cave (Málaga, Southern Spain): indirect evidence of whale consumption by humans in the Upper Magdalenian. Quaternary International 2013. Pay per viewLINK [doi:10.1016/j.quaint.2013.01.014]

Abstract

A total of 167 plates of two whale barnacle species (Tubicinella majorLamarck, 1802 and Cetopirus complanatus (Mörch, 1853)) have been found in the Upper Magdalenian layers of Nerja Cave, Mina Chamber (Maro, Málaga, southern Spain). This is the first occurrence of these species in a prehistoric site. Both species are specific to the southern right whale Eubalena australis, today endemic in the Southern Hemisphere. Because of Antarctic sea-ice expansion during the Last Glacial Period, these whales could have migrated to the Northern Hemisphere, and reached southern Spain. Whale barnacles indicate that maritime-oriented forager human groups found stranded whales on the coast and, because of the size and weight of the large bones, transported only certain pieces (skin, blubber and meat) to the caves where they were consumed.

The barnacles

According to the authors, this is the first case of consumption of whale meat and blubber ever documented in Europe. 

The hearth where the remains were found is dated to c. 14,000 years ago. 
Previous evidence from this prolific Andalusian cave have previously informed of consumption of seafood and fish, along with rabbits and the occasional goat, a tradition that dates to Neanderthal times in that region. 
A perplexing curiosity is that one of the whale kinds identified is the southern right whale, which was not known to have lived so far north at all (its main habitat is the Antarctic seas with some extension towards Brazil and the Mozambique Strait). I wonder if it is a case of misidentification and the species is either the North Atlantic right whale or an extinct relative of both.
Sources: Materia[es], Pileta[es].

PS- And what was the blubber used for (besides eating)? Our friend David Sánchez coincidentally just published two successive and quite interesting articles (in Spanish) at his blog on the lamps of the Upper Paleolithic: 1st part, 2nd part.

A particularly beautiful lamp from Lascaux (Dordogne)

Update (Jan 29): another finding of whale consumption in Magdalenian contexts unknown to me until now (h/t David) is from Las Caldas (Asturias). One of the two co-researchers is the same as the lead author of the Nerja paper → direct PDF link.

Update (Feb 22): David again added more interesting information on the matter of possible whaling in the Magdalenian period by pointing us to Colchón Rodríguez & Álvarez Fernández 2008, where they discuss (in Spanish) the presence of sea mammal remains in the cave of Las Caldas (Asturias): a seal tooth (pierced as to be part of a necklace or similar decoration), a pilot whale tooth (only initially worked), a sperm whale tooth (fully sculpted into low reliefs of whale and bison) and also several whale and other sea mammal bones used for tool-making (they made spear points on whale bone, as was documented years ago for Isturitz in the same period) and some mollusks, notably the shell of a whale barnacle (Coronula diadema).

Las Caldas (locator map) is some 20 Km. inland nowadays, in the Magdalenian period maybe 30 Km. or so. The whale barnacle suggests that whale meat was moved all that distance from the coast.

 

Ancient tsunamis of Europe

In red the tsunami sediments
Measures: height of the wave at each location

A huge tsunami probably hit the northern parts of Doggerland (the emerged landmass of what is now the North Sea) some 8000 years ago. The evidence from this catastrophic event, which probably affected the earliest inhabitants of NW Europe in a catastrophic way comes from an underwater formation off the Norwegian coast known as Storegga, which was partly demolished by the force of the giant wave, as well as from sedimentary layers at various coastal locations. The wave reached more than 20 meters at the Shetlands, where it left a 30cm-thick revealing layer.

Another possible tsunami may have affected the Southwestern coasts of Iberia in the 7th century BCE. This is currently being researched and could be related to the collapse of the semi-mythical city of Tartessos.
Sources: Meteoweb[it], Paleorama[es] (→ link 1, link 2).
 

Bronze Age rock art in Azores

The claim, even if very unexpected, seems legitimate enough to have been made by the President of the Portuguese Association of Archaelogical Research (APIA), Dr. Nuno Ribeiro, within a conference titled “pre-Portuguese human presence in Azores, myth or reality?”
Among the findings cataloged in the last few years Ribeiro mentioned building remains that seem prehistorical, a Roman era inscription, a rock art site in Terceira island and several megalithic structures. Only in the last year, five tombs of the hypogeum kind and three sanctuaries also dug in the rock were located. All the findings are still pending radiocarbon dating however but the style of the rock art is similar to Bronze Age ones from Iberia. 
However red tape by the regional government is blocking further research: in 2011 for lack of financing and in 2012 for not being withing the frame of a legal decree.  The archaeologist denounced that all these extraordinary findings are therefore in state of abandonment. In one case, works in the local airport, carried without the corresponding archaeological survey, may have damage a site.
These findings strongly suggest that the navigation skills of Bronze Age peoples of the Eastern North Atlantic (Western Europe, NW Africa) were much more advanced than we usually admit.
Source: RTP[por] (h/t Pileta).
See also these articles in English language at the Portuguese American Journal: art1, art2.

Azores are located far away into the North Atlantic Ocean (CC by Tyk)
 
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Posted by on August 28, 2012 in Azores, Bronze Age, Megalithism, navigation, Portugal, rock art, sea

 

Neolithic ship and obsidian cargo found near Naples

A sunken vessel has been discovered off the island of Capri (Campania, Italy), not far from Naples. The ship, whose details are unknown to me at the time of writing it, was tentatively dated to at least c. 5000 years ago, in the Neolithic (or earliest Chalcolithic) period. It carried a load of obsidian, a prime quality material for tools and weapons (which is said to produce sharper edges than modern surgical scalpels).
Sadly, I could not find much information on this most interesting discovery. I wonder if the obsidian was extracted from the Campi Flegrei at Naples Bay and who may have been demanding such a large cargo?

Archaeological map of Capri: red: Neolithic, yellow: Chalcolithic, other: later periods
(CC by Morn)

Sources: ANSA, Pileta.

 

Sudden major rise of sea levels after last Ice Age

I cannot find the paper right now (the CEREGE research center’s website is down?) but several news sites echo that in only 350 years, beginning 14,600 years ago, sea levels rose as much as 14 meters, judging from coral formations near Tahiti (Polynesia).
That means on average 1 meter each 25 years. The actual impact of this kind of change varies depending on the relief of the coast but nowadays one such change of just one meter would swallow about 1/3 of the Netherlands, for example.

Sources: CNRS, Pileta[es].

 
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Posted by on July 27, 2012 in climate, Ice Age, sea, Upper Paleolithic