She dined on duck, eels and hazel nuts, before settling down to a spot of tool-making, using birch bark pitch as a glue for sticking stone blades to wooden handles. The dark-haired, dark-skinned woman chewed the pitch for a while to make it more pliable, then for some reason spat out a wad without using it.

Six thousand years later archaeologists have extracted DNA from the discarded lump to shed light on the woman’s diet, appearance, and ancestry. They have named her Lola, as it was found on the island of Lolland, part of modern-day Denmark.

“It’s amazing – I know what she’s been eating, what colour her eyes were, what colour her hair was,” says Søren Sørensen at the Museum Lolland-Falster, which is running the excavation. “It’s like standing face to face with a stone age person.”

Analysis of DNA from ancient human remains such as bones and teeth has been growing in recent years, but this work is among the first to analyse prehistoric “chewing gum”. Birch pitch, made by heating the tree’s bark until it forms a black tar, was used by many ancient people as glue, for instance to stick arrow heads to their shafts or knife blades to their handles.


A piece of 6000 year-old chewing gum that was chewed by Lola (from three different angles) Theis Zetner Trolle Jensen

Small lumps of pitch have been recovered from several prehistoric sites across Europe, often with clear tooth marks. Chewing the goo would have made it more pliable. But it also has antiseptic properties so people may have chewed it to help heal mouth wounds, or even for the same reasons we chew gum today – out of hunger or boredom.

Some of the indentations are made by the small teeth of children. “Once you see kids’ teeth imprints you think it’s no different to today when kids go around spitting out chewing gum,” says Natalia Kashuba of the University of Oslo. “I want to believe that it’s also recreational, but there’s no way to know.”

Stone age chewing

In December 2018 Kashuba’s team posted online the first description of how DNA can be extracted from ancient gum, the same way we get it from fossilised lumps of poo, known as coprolites. They used it on three wads of gum dating from about 10,000 years ago, found in a hunter-gatherer site in Huseby Klev in western Sweden.

Sørensen’s team has now published their analysis of the single lump of gum from the Lolland site. They sequenced not only Lola’s DNA, but also that of the bacteria in her mouth, which suggest a diet closer to that of hunter-gatherers than what we eat today. They also recovered DNA from plants and animals that Lola had recently eaten. “You’re not only getting inside their genetics but also their lives,” says Hannes Schroeder at the University of Copenhagen, part of the team.

Until recently it wasn’t clear how stone age people could have made the pitch. The substance is still used as a home-made glue, but the bark has to be heated without oxygen, which is usually done by roasting it in a metal can. “We know that Neanderthals made pitch glue so there had to be some method simpler than using a container,” says Mikael Manninen of the University of Oslo.

In August 2017 we found out one way they could have done it: tightly rolling up sheets of birch bark, covering it with ash, to keep the air out, and then putting embers from a fire over the top.

Manninen does not recommend chewing on the pitch, though; he has tried it himself. “It has this kind of bitter taste. I didn’t chew it for long.”