MADISON, Wis., Oct. 26 (UPI) -- As scientists continue to prepare for travel to deep space, they're covering all the bases, assessing all the risks -- like the risk of microbial exposure in close quarters.
For this and other scientific reasons, researchers have been growing pathogens in space. Their most recent experiment involved Aspergillus fumigatus, the most common cause of invasive fungal infection in humans.
It turns out, this opportunistic fungus doesn't act all that differently in space as it does back on Earth.
Fungal isolates spent several months on the International Space Station (ISS). Their growth and behavior were contrasted with that of isolates back inside a lab at the University of Wisconsin.
The space-based isolates developed on unusual genetic mutations and exhibited the same in vitro growth and chemical stress tolerance measured in stateside isolates.
When a vertebrate model was exposed to the fungus, the ISS isolates proved a bit more lethal, but researchers don't believe the isolates' added potency was a result of their time spent aboard the space station.
"While we observed virulence differences, we speculate that it is completely within the variation that one would observe with terrestrial isolates," Benjamin Knox, a microbiology graduate student at Wisconsin, said in a news release. "There is an emerging body of literature showing a terrific phenotypic variation in A. fumigatus."
Though these findings -- detailed in the journal mSphere -- suggest space is not a boon to A. fumigatus, the mold pathogen remains a threat to astronaut health, one that must be accounted for.
"For people wanting to draft policy, either sampling or cleaning regimes aboard these space vessels, the study shows that if a fungus is identified as A. fumigatus, any and all isolates represent potential pathogens and should be treated as such," Knox said.
CANTABRIA, Spain, Oct. 26 (UPI) -- Scientists believe the Eurasian cave lion was the largest lion species to ever walk the Earth. Unfortunately, it's no longer with us. According to a new study in the journal PLOS ONE, humans of the Late Stone Age may be to blame.
New evidence uncovered by scientists in Spain suggests some Upper Paleolithic hunters may have dabbled in the lion trade. Until now, evidence of lion exploitation has proven elusive.
At a cave site called La Garma in northern Spain, researchers recovered cave lion bones with marks similar to those found on the bones of prey skinned by modern hunters. The marks are unique to a skinning technique used to keep the claws of the animal attached to its fur.
Radiocarbon dating suggests the lion was killed between 14300 and 14000 B.C. Cave lions went extinct not long after 14000 BC.
The evidence suggests the recovered cave lion toe bones may have been attached to a pelt that lay permanently on the floor of a cave. La Garma is known as a host site for early human rituals; the cave lion may have been an animal of symbolic importance.
Researchers acknowledge their hypothesis is just one of several possible scenarios.
"It is by no means clear that our results point towards a unique and unequivocal archaeological evidence of cave lion exploitation," scientists wrote.
But if correct, scientists argue the "outstanding evidence" could serve as a "speculative alternative explanation to cave lion extinction during the Late Pleistocene."