Report

Teaser, summary, work performed and final results

Periodic Reporting for period 2 - Lost Frontiers (Europe’s Lost Frontiers: exploring climate change, settlement and colonisation of the submerged landscapes of the North Sea basin using ancient DNA, seismic mapping and complex systems modelling)

Teaser

The only lands on Earth that have not been explored in any depth by science are those that have been lost to the oceans. Global warming at the end of the last Ice Age led to the inundation of vast landscapes that had once been home to thousands of people. These lost lands hold...

Summary

The only lands on Earth that have not been explored in any depth by science are those that have been lost to the oceans. Global warming at the end of the last Ice Age led to the inundation of vast landscapes that had once been home to thousands of people. These lost lands hold a unique and largely unexplored record of settlement and colonisation linked to climate change over millennia. Amongst the most significant is Doggerland.

Occupying much of the North Sea basin between continental Europe and Britain, Doggerland would have been a heartland of human occupation and central to the process of re-settlement and colonisation of north western Europe during the Mesolithic and the Neolithic. Within this submerged landscape lies fragmentary yet invaluable evidence for the lifestyles of its inhabitants including the changes resulting from both the encroaching sea and the introduction of Neolithic technologies and practise.

This inundated landscape cannot be explored nor analysed conventionally, however pioneering work by the applicant’s research group using seismic reflection data has led to the rediscovery of Doggerland through the creation of the first maps showing rivers, lakes, hills and coastlines relating to human occupation in the Early Holocene. Using these base data this project aims to transform our understanding of the colonisation and development of floral, faunal and human life during this critical period of history through the development and application of a suite of innovative methods and research approaches that will:

1) release the full potential of the vast seismic reflectance data sets available to generate topographical maps of the whole of early Holocene Doggerland that are as accurate and complete as possible.

2) reconstruct and simulate the palaeo-environments of Doggerland using ancient DNA extracted directly from sediment cores (rather than from fossils), along routes of two submerged river valleys.

3) explore the Mesolithic landscapes and identify incipient Neolithic signals indicating early contact and development within the region of Doggerland.

Led by world-leading innovators in the fields of archaeo-geophysics, molecular biology and computer simulation, the project seeks to develop a ground-breaking new paradigm for the study of past environments, ecological change and the transition between hunter gathering societies and farming in north west Europe.

Work performed

The activities during the first half of the Europe’s Lost Frontiers project have focussed on obtaining and analysing the seismic mapping data and then using this data to identify locations for coring. We have then taken cores from these locations and are assessing and analysing their contents.
We have obtained over 77,000 km2 seismic data from PGS which we have not only used to choose suitable locations for coring but are also using to expand existing maps of Doggerland. 48,000km2 of the early Holocene landscape has been mapped by previous projects. We currently have processed and analysed 27,000km2 and by the end of the project we expect to have completed the outstanding 2,000km2. In this newly analysed area, we have discovered previously unknown rivers, coastlines, valleys and lakes at the heart of the Doggerland landscape.

The coring was carried out on two different trips: one undertaken by Gardline in September 2016 and the other undertaken by MG3 in August-September 2017. Cores from 20 locations were taken during 2016 and from a further 40 locations in 2017. These locations were chosen based on their likely archaeological potential and the depth of modern deposits on top of the earlier landscape features. These cores have been more successful than we anticipated, with over 75% containing material from the period before the area below the Southern North Sea was flooded. These cores have now been assessed in order to see what biological remains might be present and we have discovered that foraminifera, ostracods, diatoms, pollen, molluscs, plant macro fossils, sedimentary ancient DNA (sedaDNA) and insects are preserved to varying degrees. We are now starting to assess the quality of this material and have undertaken some limited analysis.

The number of techniques used to examine the cores has expanded since the original application. We are currently analysing pollen, foraminifera, ostracods, diatoms, molluscs, lipids and sedimentary DNA from the cores. We will be dating the deposits within the cores using radiocarbon dating, Optically Stimulated Luminescence and magnetic dating methods. Dating and analysis is almost finished on one important core from the first batch. Due to the sheer amount of data being recovered from our cores, it has been necessary to focus our attention on a small number of cores in order to answer our research questions regarding the transition from mobile hunter-gatherers to sedentary farming communities and how this was affected by the progressive inundation of the landscape.

Final results

This is the first time that a program of environmental archaeology looking at pollen, diatoms, molluscs, plant macrofossils and insects has been attempted for archaeological purposes at this scale in the North Sea basin. Some of these techniques are well established but some are new and using these techniques as part of a package in order to investigate drowned landscapes is a unique undertaking.

This scale of sampling of sedaDNA for archaeological landscape reconstruction is unprecedented both on land and within inundated landscapes such as that found within the North Sea and, in combination with the wide range of other proxies sampled, enables us to probe complex questions about palaeolandscapes and DNA taphonomy.

DNA damage patterns are commonly used in the authentication of ancient DNA, however, the impacts of the environment on these patterns are poorly understood. To date, analysis of DNA damage has been limited to a narrow training set of samples which do not represent any marine environments. This project has afforded us a unique opportunity to probe the impact of a wide variety of marine environments on DNA breakdown, and to transform expectations about DNA preservation.

Due to the extent and resolution of the datasets, the seismic mapping process will produce a much more extensive and detailed map of the pre-inundation landscape of Doggerland than has ever been seen before.
The various types of environmental archaeology analysis will be combined to reconstruct the nature of the landscape and the vegetation before the North Sea basin flooded. This information will also be used to support the sedaDNA analysis. The wide variety of types of evidence will form an array of proxies for the effects of a changing climate on the landscape.

In combination with the other proxies, the sedaDNA provides a detailed snapshot of the past environments of the North Sea, across spatial and temporal scales. This allows us to test the hypothesis of Neolithic activity on the North Sea plain prior to the inundation, whilst also developing our understanding of the inundation process.

By exploiting the wide variety of environmental and sediment types retrieved by coring, we are able to establish the significance of environmental parameters for DNA preservation and the interactions of DNA with sediment. This is complimented and extended by the extensive experimental work.

In addition to the current Lost Frontiers sedaDNA research, the group at the University of Warwick have also been involved with a project examining the role in which post-depositional taphonomy and environmental conditions impact on the degradation of ancient DNA. This project is studying sedimentary DNA from intertidal deposits from cores taken Cardigan Bay, West Wales. Although this is a different location to the primary research of the Lost Frontiers coring Project, the results will provide a valuable contextual for the potential of extracting sedaDNA from similar deposits of silts, sands and clays from the North Sea cores.

The data from the mapping and cores will be combined within simulations that will allow us to test hypotheses regarding the changing landscape and its effects on the human inhabitants of Doggerland. This will not only allow us to combine data from sources outside the project and from the areas around Doggerland with that from our cores and maps, but also allow us to identify indirect markers of human activity in a manner never previously attempted. This will both help us extract the maximum values from our data and help similar projects around the world use these techniques to confront their own regional archaeological and environmental challenges.

Website & more info

More info: http://www.lostfrontiers.org.uk.