For once I have a decent mix of interesting science-related news announcements that are not all centered around biology.

• The one medical paper in this lot is rather sobering one about the long-term risk of regularly using marijuana. The study uses insurance data and claims that those who use the substance daily for years, and especially those with cannabis use disorder, meaning that they overuse it, have a much higher risk of developing head and neck cancers. As they note, they didn’t differentiate between methods of using the substance and it could be that the increased risk comes mainly from smoking it rather than the substance itself. Still with marijuana use becoming more socially and legally acceptable, usage rates are shooting up and the long-term effects do call for greater scrutiny.
• Then there’s this paper that has major implications for all of life on Earth so I supposed it counts as being biology-related. It concerns the discovery of so-called dark oxygen, referring to oxygen made by metallic nodules deep under the surface of the ocean. This presents a challenge to the conventional assumption that all oxygen on Earth is produced by living organisms through processes like photosynthesis using sunlight. The nodules however seem to be able to create oxygen using a sort of seawater electrolysis process, effectively acting like natural batteries. The discovery opens new possibilities for the ongoing search into how life began on our planet as aerobic life might well have begun deep under the ocean where there is no sunlight.
• Next is another finding that is planetary in scale but it’s about Mars. By analyzing data from a seismometer carried on Nasa’s Mars Insight Lander, the team claims that they have found liquid water in reservoirs deep in the rocky crust of the planet. Though we already know that there is water frozen at the poles of Mars, this is the first time that liquid water has been found there. At around 10 km to 20km beneath the surface, the reservoir is still far too deep to be of practical use but it does help answer the question of where all of the water that was known to be Mars go.
• Finally here’s a paper that hit news headlines around the world. By analyzing the composition of the central Altar Stone that is part of Stonehenge, the team claims that it must have come from Scotland at least 750 km away. As the stone is thought to have arrived at Stonehenge around 2620 to 2480 BC, this represents a considerable feat of transportation and logistics. More interesting to me is what it tells us about the importance of the site as the builders deemed it necessary to transport a stone so far and what that implies for the level of societal organization that existed even so long ago.