Maritime diffusion route for European megalithic structures

This is an interesting paper which claims to replace the old theories of cultural diffusion with a new one.   There seems to be good evidence that the oldest structures were put up in Brittany, around Carnac, but for later phases the picture is very confused, apparently demonstrating coastal diffusion -- as already claimed by lots of other people -- and I cannot see any great justification for the red, green, yellow and brown phase.  It all looks rather scrappy to me, involving a degree of academic wishful thinking.

In the British Isles, classified as a "green phase" region, the earliest structures seem to have been erected in Scotland, followed by the south of  England, and then by Ireland and Wales.   That does not seem to make much sense if the "duffusion centre" really was in Brittany. 

In a press article about this paper, the author claims that this thesis supports the idea of bluestone transport from Pembrokeshire to Stonehenge -- presumably by the maritime route.  However, I cannot see that at all in the new evidence -- and if anything we might claim that the diffusion was westwards from southern England towards Wales, rather than the other way round..........

This is another interesting diagram that does not appear in the original article.  It is included in some of the press coverage -- so was presumably included in the author's press release.  It shows England, Scotland and Ireland clustered together (whatever happened to Wales?) as having a phase of pit burials around 6000 yrs BP,  followed shortly thereafter by  a phase of passage grave building.  Presumably the author assumes that stone circles, alignments and other bit megalithic arrangements (including Stonehenge) came along even later. 

In the press coverage, there appears to be a degree of scepticism among archaeologists about this new work, partly on the grounds that it does not factor in the likelihood that stone-using traditions could well have developed quite independently in various widely-separated geographical locations.  Diffusion models do have that as a major flaw -- for example, is it likely that the wheel developed in just one place and then spread out from there, or could many individuals in different parts of the world have developed their own prototype wheels in isolation? 

===================

Radiocarbon dates and Bayesian modeling support maritime diffusion model for megaliths in Europe

B. Schulz Paulsson
PNAS published ahead of print February 11, 2019
https://doi.org/10.1073/pnas.1813268116
approved January 3, 2019
https://www.pnas.org/content/early/2019/02/05/1813268116

Significance

For thousands of years, prehistoric societies built monumental grave architecture and erected standing stones in the coastal regions of Europe (4500–2500 calibrated years BC). Our understanding of the rise of these megalithic societies is contentious and patchy; the origin for the emergence of megalithic architecture in various regions has been controversial and debated for over 100 y. The result presented here, based on analyses of 2,410 radiocarbon dates and highly precise chronologies for megalithic sites and related contexts, suggests maritime mobility and intercultural exchange. We argue for the transfer of the megalithic concept over sea routes emanating from northwest France, and for advanced maritime technology and seafaring in the megalithic Age.

Abstract

There are two competing hypotheses for the origin of megaliths in Europe. The conventional view from the late 19th and early 20th centuries was of a single-source diffusion of megaliths in Europe from the Near East through the Mediterranean and along the Atlantic coast. Following early radiocarbon dating in the 1970s, an alternative hypothesis arose of regional independent developments in Europe. This model has dominated megalith research until today. We applied a Bayesian statistical approach to 2,410 currently available radiocarbon results from megalithic, partly premegalithic, and contemporaneous nonmegalithic contexts in Europe to resolve this long-standing debate. The radiocarbon results suggest that megalithic graves emerged within a brief time interval of 200 y to 300 y in the second half of the fifth millennium calibrated years BC in northwest France, the Mediterranean, and the Atlantic coast of Iberia. We found decisive support for the spread of megaliths along the sea route in three main phases. Thus, a maritime diffusion model is the most likely explanation of their expansion.