Ritualised heads on stakes. Stone Age society and Stone Age people’s conception of the world were more complex than previously believed. This according to new analyses of skulls found in Motala, Sweden.

Anterior view of crania F296 showing well-preserved facial bones  [Credit: Sara Gummesson et al., 2018]

“The majority of the crania have traces of healed injuries in the same area of the head. It seems repetitive and there are differences between women and men”, Anna Kjellström says. She works at the Stockholm University Osteoarchaeological Research Laboratory and she is one of researchers who have examined the skulls.

Cranium F318 with wooden stake [Credit: Fredrik Hallgren]

The skulls come from a former lake in Motala, in eastern-central Sweden, excavated 2009–2013. Archaeologists found, among other things, remnants from at least ten people: nine adults and one infant. Two of the skulls were still mounted on stakes and at least seven had traces of healed injuries not caused by falling by incident.

These skulls, collected from the Kanaljorden burial, show signs of blunt-force trauma [Credit: Karin Berggren and Fredrik Hallgren; Antiquity 2018]

The women’s head injuries were in the back and on the right side of the head while the male skulls had injuries on the top of the head and in the face. The researchers also believe that after death the bodies were stored or buried in another place and then transported to the place where they were found.

People of importance

“The fact that so many had healed injuries suggests that these people were special in some way”, Anna Kjellström says.

A model showing the local topography at Kanaljorden. The black outline details where the excavation took place. The black dots show the burial's location in the ancient lake [Credit: Karin Berggren and Fredrik Hallgren; Antiquity 2018]

The great number of findings and their concentration to one place make the researchers believe that these people were of importance. There are no similar findings in Europe, Anna Kjellström says.

The burial was large, about 39 feet by 46 feet (12 by 14 meters). The bottom of the burial was made of large stones and wooden stakes. On top of the packed stone, Stone Age people placed the bones in a certain order. The humans (red) were in the middle, while the brown bears (blue) were south of the humans and the wild boar (yellow) were southeast of the humans [Credit: Sara Gummesson et al./Antiquity 2018]

During the Old Stone Age period, 8,000 to 7,500 years ago, humans were hunter-gatherers living in smaller groups following animals according to season. But there were places where many groups of people gathered at certain times during the year. These places were of great ceremonial importance and people could build more permanent structures there.

Complex Stone Ace society

“Our findings give a more nuanced image of the Stone Age – it was a complex society with clear signs of planning and organisation”, Anna Kjellström says. The handling of human remains allows researchers to get an idea of the large world of religious notions that existed during the Stone Age.

Cut marks on the bear's jaw that are indicative of butchery [Credit: Sara Gummesson et al.; Antiquity 2018]

“Placing heads on stakes may have been some kind of intimidation tactic to scare enemies, but the action might as well have had a different meaning for ancient people than today. In any case, it must have been a striking and spectacular view”, Anna Kjellström says.

The study was published in the journal Antiquity.

Source: Stockholm University [February 22, 2018]

Directly following the last ice age, people from the western parts of what is now Norway were a population that had substantially different genetics from the people living in the area corresponding to present-day Sweden.

Anne-Marian Snaaijer, a PhD candidate at the Norwegian University of Science and Technology works in Trondheim's Archive Centre at Dora. The collection trays hold lots of bone discoveries [Credit: Åge Hojem, NTNU University Museum]

"We were surprised that the results showed such marked dissimilarities," says associate professor and archaeologist Birgitte Skar at the Norwegian University of Science and Technology's (NTNU) University Museum. Skar is responsible for the museum's Stone Age and Bronze Age collections.

Scandinavia was one of the last parts of Europe to become habitable when the glaciers released their icy grip more than 10,000 years ago. The ocean's resources and the coastal archipelago attracted marine hunter-gatherers of yore to the region.

Swedish and Norwegian researchers have collaborated on analysing the DNA in 9500-year-old bone samples from the southern and western Norwegian coast and from the Swedish islands of Gotland and Stora Karlsö. This period corresponds to the Mesolithic Stone Age.

Researchers examined seven excavated individuals and compared their genetic material with samples from other parts of Europe.

"People from the Norwegian south and west coast were genetically similar to populations east of the Baltic Sea that came from today's Russia. People from eastern Scandinavia - present-day Sweden - were more genetically similar to populations from central and western Europe," says population geneticist Torsten Günther from Uppsala University. He is one of the main authors of the new study.

Norwegian results are key

This finding may seem strange if you just look at the geography, but it may due to multiple waves of migration to Scandinavia. About 11,500 years ago, people migrated from the south, through Germany and Denmark and then by sea to Norway. About 1000 years later, people traveled from the northeast and followed the Norwegian Atlantic coast southward.

"To understand the migration routes, it was essential to obtain data from the Norwegian individuals," explains Skar, co-author of the study. The Norwegian skeletal remains from southern Norway are also the oldest of the individuals studied.

Over time, the various migration waves led to extensive contact between the diverse populations, and this is also reflected in the genetic data.

The researchers analysed the genetic data in conjunction with other archaeological findings and new insights from climate models to increase their understand of the migration routes, settlement patterns and the first people to settle in Scandinavia as the ice retreated.

Archaeological artefacts and isotopic analysis - which can tell us something about what people ate - help to fill out the picture. The new immigrants that came from the northeast learned new boating and fishing skills to access marine resources, which offered their main source of food.

The researchers discovered that these immigrants also introduced new tools and innovative ways to produce them. This shift in material culture can now be linked to a particular migration wave.

"We expect that a migrating population comes with an entire cultural package - a knowledge of nature, ways of life, craft traditions, beliefs and other customs," says Skar. "Now we can explore more closely how the relationship between the original and new populations evolved. The original inhabitants were highly skilled and adventurous seafaring hunters, whereas the new population was originally an inland people. Archaeologists can track the processes of change in their material culture," she adds.

Light pigmentation variants may have been advantageous

People at that time were largely dependent on the ocean for food. They braved challenging climate conditions that required behavioral adaptations in the short term, and that in the longer term could lead to changes in the population's genetic composition.

"The two groups that migrated to Scandinavia at that time were genetically distinct. People from the south probably had blue eyes and dark skin, while those from the northeast had various eye colours and light skin," says population geneticist Mattias Jakobsson from Uppsala University, another of the main authors.

The genetic variation between the Mesolithic individuals from Scandinavia is surprisingly high, and greater than in the populations who lived in western and central Europe. This contrasts with the Europe of today, where the largest genetic variation is found in the south.

The lighter variations of skin and eye color that are more common in Scandinavia than in other parts of Europe also appear to have been the case at the time of the migrations. Pigmentation, now as then, tends to decrease the farther away a population group lives from the equator. We can assume this to be an indicator of climate adaptation.

Good results

The results are presented in a research article recently published in PLoS Biology. The sample quality is very high.

The remains of one of the individuals studied yielded aDNA results with the best coverage, or depth, achieved for any human being from prehistoric times. The abbreviation aDNA stands for ancient DNA and refers to the study of genetic data obtained from fossil subjects.

Source: Norwegian University of Science and Technology [February 01, 2018]

An international team of scientists, led by researchers from the Max Planck Institute for the Science of Human History, analyzed ancient human genomes from 38 northern Europeans dating from approximately 7,500 to 500 BCE. The study, published in Nature Communications, found that Scandinavia was initially settled via a southern and a northern route and that the arrival of agriculture in northern Europe was facilitated by movements of farmers and pastoralists into the region.

Skull included in this study from Ölsund, Hälsingland, Sweden, dating to around 2,300 BCE, in the ancient DNA laboratory at the Max Planck Institute for the Science of Human History [Credit: Alissa Mittnik]

Northern Europe could be considered a late bloomer in some aspects of human history: initial settlement by hunter-gatherers occurred only about 11,000 years ago, after the retreat of the lingering ice sheets from the Pleistocene, and while agriculture was already widespread in Central Europe 7,000 years ago, this development reached Southern Scandinavia and the Eastern Baltic only millennia later.

Several recent studies of ancient human genomes have dealt with the prehistoric population movements that brought new technology and subsistence strategies into Europe, but how they impacted the very north of the continent has still been poorly understood.

For this study, the research team, which included scientists from Lithuania, Latvia, Estonia, Russia and Sweden, assembled genomic data from 38 ancient northern Europeans, from mobile hunter-gatherers of the Mesolithic (approximately 12,000 to 7,000 years ago) and the first Neolithic farmers in southern Sweden (approximately 6,000 to 5,300 years ago) to the metallurgists of the Late Bronze Age in the Eastern Baltic (approximately 1300 to 500 BCE). This allowed the researchers to uncover surprising aspects of the population dynamics of prehistoric northern Europe.

Two routes of settlement for Scandinavia

Previous analysis of ancient human genomes has revealed that two genetically differentiated groups of hunter-gatherers lived in Europe during the Mesolithic: the so-called Western Hunter-Gatherers excavated in locations from Iberia to Hungary, and the so-called Eastern Hunter-Gatherers excavated in Karelia in north-western Russia. Surprisingly, the results of the current study show that Mesolithic hunter-gatherers from Lithuania appear very similar to their Western neighbors, despite their geographic proximity to Russia. The ancestry of contemporary Scandinavian hunter-gatherers, on the other hand, was comprised from both Western and Eastern Hunter-Gatherers.

Map showing locations and timeline of the samples introduced in this study [Credit: Mittnik et al. Nature Communications (2018)]

"Eastern Hunter-Gatherers were not present on the eastern Baltic coast, but a genetic component from them is present in Scandinavia. This suggests that the people carrying this genetic component took a northern route through Fennoscandia into the southern part of the Scandinavian peninsula. There they genetically mixed with Western Hunter-Gatherers who came from the South, and together they formed the Scandinavian Hunter-Gatherers," explains Johannes Krause, Director of the Department of Archaeogenetics at the Max Planck Institute for the Science of Human History, and senior author of the study.

Agriculture and animal herding - cultural imports by incoming people

Large-scale farming first started in southern Scandinavia around 6,000 years ago, about one millennium after it was already common in Central Europe. In the Eastern Baltic, the inhabitants relied solely on hunting, gathering and fishing for another 1000 years. Although some have argued that the use of the new subsistence strategy was a local development by foragers, possibly adopting the practices of their farming neighbors, the genetic evidence uncovered in the present study tells a different story.

The earliest farmers in Sweden are not descended from Mesolithic Scandinavians, but show a genetic profile similar to that of Central European agriculturalists. Thus it appears that Central Europeans migrated to Scandinavia and brought farming technology with them. These early Scandinavian farmers, like the Central European agriculturalists, inherited a substantial portion of their genes from Anatolian farmers, who first spread into Europe around 8,200 years ago and set in motion the cultural transition to agriculture known as the Neolithic Revolution.

Similarly, a near-total genetic turnover is seen in the Eastern Baltic with the advent of large-scale agro-pastoralism. While they did not mix genetically with Central European or Scandinavian farmers, beginning around 2,900 BCE the individuals in the Eastern Baltic derive large parts of their ancestry from nomadic pastoralists of the Pontic-Caspian steppe.

"Interestingly, we find an increase of local Eastern Baltic hunter-gatherer ancestry in this population at the onset of the Bronze Age," states Alissa Mittnik of the Max Planck Institute for the Science of Human History, lead author of the study. "The local population was not completely replaced but coexisted and eventually mixed with the newcomers."

This study emphasizes the regional differences of cultural transitions and sets the stage for more in-depth studies of later periods in northern European prehistory, such as the Iron Age and Viking Age.

Source: Max Planck Society [January 30, 2018]

Two shipwrecks, including one possibly dating back to the 14th century, have been found at the bottom of the sea as part of a project to open a new maritime museum in Stockholm.

The cog, from the 14th or 15th century [Credit: Mikael Fredholm/Swedish National Maritime Museums]

Maritime archaeologists made the discoveries just before Christmas while diving in the archipelago to take pictures and gather material for the planned museum, a spokesperson for the Swedish National Maritime Museums told The Local.

Historic vessels are a fascinating, but not unusual, discovery in the Baltic Sea's shipwreck graveyard (there are at least 100 intact ships on the Baltic seabed). The water is too brackish for shipworm, which means that a huge number of wooden ships have survived on the bottom of the sea with almost intact hulls for centuries.

Another picture of the cog [Credit: Mikael Fredholm/Swedish National Maritime Museums]

Most shipwrecks found in Stockholm are from the 17th and 18th centuries, Sweden's maritime heyday, but one of the new finds is thought to be from the 14th or 15th century. Mostly submerged in the mud on the seabed, the wrecked ship – believed to be a cog – is 23-25 metres long and seven metres wide.

"My pulse went up when I realized what we were looking at – I have never seen such well-preserved shipwrecks," said maritime archaeologist Jim Hansson in a statement.

Barrels containing osmond iron and tar [Credit: Jim Hansson/Swedish National Maritime Museums]

Onboard the other shipwreck, estimated to be from the 16th century, a whopping 20 barrels of osmond iron, kitchen utensils and tools were found. The National Maritime Museums said the extent of the iron found was "unprecedented in previous maritime findings". The exact location of the wrecks has not been revealed.

The planned maritime archaeological museum 'Treasures of the Baltic Sea' is scheduled to open in 2020 next to the Vasa Museum on Djurgården island in Stockholm. But it is unlikely that any new wrecks found will be turned into a new version of world-famous warship Vasa, which sank in 1628 and was salvaged in 1961.

A 3D image of the cog wreck [Credit: Swedish National Maritime Museums]

"There will be both authentic exhibits in the new museum such as objects found and parts of wrecks. But no whole wrecks like the Vasa ship, because the wrecks are best preserved by staying where they are now," Cecilia Eriksson, communication officer of the Swedish National Maritime Museums, explained to The Local.

"Instead, visitors will get to join dives deep into the secrets of the Baltic Sea with the help of digital technology," she said.

Author: Emma Löfgren | Source: The Local [January 28, 2018]