They look like shrivelled pieces of leather – in fact they are dried communities of microbes scooped up by Captain Robert Falcon Scott’s team of polar explorers. And they could help scientists keep tabs on how Antarctica is changing.

While perhaps most famous for the ill-fated Terra Nova expedition from 1910-13, Scott also led the 1901-4 Discovery Expedition to Antarctica that was proclaimed a success, largely due to the pioneering scientific studies carried out on the trip. Among the research carried out during this earlier mission, the team collected a host of specimens including samples of microbial mats – layered, sheet-like structures that can grow in lakes and ponds.

“They are like biofilms. They are similar to in the UK where on a river, on the stones, it is all slimy,” said Dr Anne Jungblut, first author of the new study from the Natural History Museum in London, adding that in Antarctica where there are no insects to graze on the mats the structures can grow to a few centimetres in thickness.





A specimen of freshwater cyanobacteria collected on the McMurdo Ice Shelf, Antarctica during Captain Scott’s Discovery Expedition in December 1902. Photograph: Dr Anne Jungblut/Natural History Museum

“[The mats] are made out of these cyanobacteria, which are more commonly known as blue-green algae,” said Jungblut, noting that other microbes live on the resulting structures. “Antarctica is thought of being either ice covered or there is nothing living, but as soon as you get freshwater, you get these microbial mats.”

The six samples were collected in 1902and come from two locations: Ross island, where Scott and his team had their winter quarters, and an area of the McMurdo ice shelf that the team probably reached on foot or on dog-pulled sledges. While few in number, “to actually still have them from Scott’s expedition is really amazing and unique,” said Jungblut.

While it is not clear exactly who collected and pressed the samples, Jungblut has a shrewd idea.

The crew produced a fake newspaper, in it they talked about how Koettlitz collected weird smelly things and dried them.

The expedition crew produced a fake newspaper while in Antarctica, the South Polar Times. In it, “they talk about how Dr Reginald Koettlitz collected all sorts of weird and smelly things and dried them,” said Jungblut.



Using small pieces from the samples, Jungblut and colleagues had previously probed their makeup. “The samples 100 years ago, they are not identical, but they are very similar to modern blue-green algae communities in the Antarctic,” said Jungblut. But the new study goes further, exploring whether the samples contain toxins produced by cyanobacteria.

Writing in the European Journal of Phycology, the team reveal that the samples do indeed contain toxins, including a substance toxic to the liver and several forms of a neurotoxin known as BMAA.

The Discovery Hut on Ross Island with the US Antarctic McMurdo station in the background. Photograph: Dr Anne Jungblut/Natural History Museum

While both types of toxins were lower in concentration than would be found in algal mats in the UK, for example, concentrations of the liver toxin were similar to those found in modern samples form Antarctica, while it is the first time BMAA has been reported in a cyanobacterial mat from the continent.

But, Jungblut notes, questions remain including whether the toxins have degraded over time, with the possibility that toxin concentrations might have been higher in the past. “Usually if you get an environmental sample you would try to freeze it as quickly as possible to try and preserve everything,” she said. “But these were stored for a hundred years in a cupboard in a Victorian building.”

Despite the uncertainties, Jungblut said the latest research gives a useful baseline of conditions in the area, allowing scientists to probe the impact of future warming and invasive species that could potentially be brought to Antarctica by increased human activity. “If we find in the future a lot higher concentrations we know that something might be changing,” she said, noting that higher concentrations, or different types of toxins, could affect wildlife.

The new research, Jungblut adds, underscores the importance of Scott’s expeditions and the research the team undertook. “It highlights the legacy of these samples,” she said.