Bronze Age Scandinavia's trading networks for copper settled

Bronze Age Scandinavia's trading networks for copper settled

Crossing the North Sea before crossing the Alps!

trading bronze age Scandinavia's
Shafthole axe type Fårdrup. This axe is of Nordic craftsmanship and hides information on the first attempt to establish trading networks with societies across the Alps. A small group of these Nordic crafted axes is made of northern Italian copper, so called AATV-copper (from the Alto Adige, Trentino and Veneto mining region in the Italian Alps) while the majority of these axes is made of British and Welsh or eastern Alpine metal. Photo credits: Heide W. Nørgaard, by permission of the National Museum, Copenhagen

New research presents over 300 new analyses of bronze objects, raising the total number to 550 in 'the archaeological fingerprint project'. This is roughly two thirds of the entire metal inventory of the early Bronze Age in southern Scandinavia. For the first time, it was possible to map the trade networks for metals and to identify changes in the supply routes, coinciding with other socio-economic changes detectable in the rich metal-dependent societies of Bronze Age southern Scandinavia.

The magnificent Bronze Age in southern Scandinavia rose from copper traded from the British Isles and Slovakia 4000 years ago. 500 years later these established trade networks collapsed and fresh copper was then traded from the southern Alps, the so-called Italian Alps. This large-scale study could show that during the first 700 years of the Nordic Bronze Age the metal supplying networks and trade routes changed several times. These 700 years of establishment and change led to a highly specialised metalwork culture boasting beautiful artwork such as the Trundholm Sun wagon and spiral decorated belt plates branding high-ranking women; even depicted on today's Danish banknotes.

The lead isotope plot of the over 65 shafthole axes analyzed in this study dating to the end of the first Bronze Age period 1600 BC. This amount of data exceeds the previous analyses by ten times and for the first time allows to compare both axe types and understand their development

The study by H. Nørgaard, Moesgaard Museum and her colleagues H. Vandkilde from Aarhus University and E. Pernicka from the Curt-Engelhorn Centre in Mannheim built on the so far largest dataset of chemical and isotope data of ancient bronze artefacts. In total 550 objects were used to model the changes that took place: These changes correlate with major shifts in social organisation, settlements, housing, burial rites and long distance mobility.

trading bronze age Scandinavia's
Shafthole axe of Valsømagle type. Only a few axes of this type are known, and they are only distributed in northern Europe. These axes seem to be contemporary with the Fårdrup type axes as they are made of the same metal and not, if they would be slightly later, of the new Italian metal that is the main metal used in the period from 1500 BC. Photo credits: Heide W. Nørgaard, by permission of the National Museum, Copenhagen

"Now, this multi-disciplinary approach - based jointly on conventional archaeological methods and novel scientific methodologies processing large data quantities - allows us to detect these correlating changes and identify contemporaneity with societal changes recognised by colleague researchers", says Heide Nørgaard the project´s PI.

"It is highly likely that both people and technologies arrived to Scandinavia and that Scandinavians travelled abroad to acquire copper by means of the Nordic amber, highly valued by European trading partners".

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Citation: Nørgaard HW, Pernicka E, Vandkilde H (2021) Shifting networks and mixing metals: changing metal trade routes to Scandinavia correlate with Neolithic and Bronze Age transformations. PLOS ONEhttps://journals.plos.org/plosone/article?id=10.1371/journal.pone.0252376

 

Bronze Age Scandinavia's trading networks for copper settled: press release from Aarhus University.


ADHD neanderthals

A genomic analysis in samples of Neanderthals and modern humans shows a decrease in ADHD-associated genetic variants

A genomic analysis in samples of Neanderthals and modern humans shows a decrease in ADHD-associated genetic variants

According to the study, some features like hyperactivity or impulsiveness could have been favourably selected for survival in ancestral environments dominated by a nomad lifestyle

The frequency of genetic variants associated with attention-deficit/hyperactivity disorder (ADHD) has decreased progressively in the evolutionary human lineage from the Palaeolithic to nowadays, according to a study published in the journal Scientific Reports.

The new genomic analysis compares several ADHD-associated genetic variants described in current European populations to assess its evolution in samples of the human species (Homo sapiens), modern and ancient, and in samples of Neanderthals (Homo neanderthalensis). According to the conclusions, the low tendency observed in European populations could not be explained for the genetic mix with African populations or the introgression of Neanderthal genomic segments in our genome.

The new genomic study isled by Professor Bru Cormand, from the Faculty of Biology and the Institute of Biomedicine of the University of Barcelona (IBUB), the Research Institute Sant Joan de Déu (IRSJD) and the Rare Diseases Networking Biomedical Research Centre (CIBERER), and the researcher Oscar Lao, from the Centro Nacional de Análisis Genómico (CNAG), part of the Centre for Genomic Regulation (CRG). The study, whose first author is the CNAG-CRG researcher Paula Esteller -current doctoral student at the Institute of Evolutionary Biology (IBE, CSIC-UPF)- counts on the participation of research groups of the Aarhus University (Denmark) and the Upstate Medical University of New York (United States).

TDAH neandertales
The experts Paula Esteller, Bru Cormand and Òscar Lao

ADHD: an adaptive value in the evolutionary lineage of humans?

 The attention deficit/hyperactivity disorder (ADHD) is an alteration of the neurodevelopment which can have a large impact on the life of the affected people. Featured by hyperactivity, impulsiveness and attention deficit, it is very common in modern populations -with a prevalence of 5% in children and adolescents- and can last up to adulthood.

From an evolutionary perspective, one would expect that anything detrimental would disappear among the population. In order to explain this phenomenon, several natural hypotheses have been presented -specially focused on the context of transition from the Palaeolithic to the Neolithic-, such as the known Mismatch Theory.

“According to this theory, cultural and technological changes that occurred over the last thousands of years would have allowed us to modify our environment in order to adopt it to our physiological needs in the short term. However, in the long term, these changes would have promoted an imbalance regarding the environment in which our hunter-gatherer ancestors evolved”, note the authors.

Therefore, several traits like hyperactivity and impulsiveness -typical in people with ADHD- could have been selectively favoured in ancestral environments dominated by a nomad lifestyle. However, the same features would have become non-adaptive in other environments related to more recent times (mostly sedentary).

Why is it one of the most common disorders in children and adolescents?

 The new study, based on the study on 20,000 ADHD affected people and 35,000 controls, reveals the genetic variants and alleles associated with ADHD tend to be found in genes which are intolerant to mutations that cause loss of function, which shows the existence of a selective pressure on this phenotype.

According to the authors, the high prevalence of ADHD nowadays could be a result from a favourable selection that took place in the past. Although being an unfavourable phenotype in the new environmental context, the prevalence would still be high because much time has not passed for it to disappear. However, due to the absence of available genomic data for ADHD, none of the hypothesis has been empirically contrasted so far.

“Therefore, the analysis we conducted guarantee the presence of selective pressures that would have been acting for many years against the ADHD-associated variants. These results are compatible with the mismatch theory but they suggest negative selective pressures to have started before the transition between the Palaeolithic and the Neolithic, about 10,000 years ago”, say the authors.

Reference Article:

 Esteller-Cucala, P.; Maceda, I.; Børglum, A.D.; Demontis, D.; Faraone, S.V.; Cormand, B.; Lao, O. “Genomic analysis of the natural history of attention-deficit/hyperactivity disorder using Neanderthal and ancient Homo sapiens samples”. Scientific Reports, May,  2020. Doi: 10.1038/s41598-020-65322-4

 

Press release from the University of Barcelona