In this episode of the Nature Podcast, we catch up on some science stories from the holiday period by diving into the Nature Briefing. 00:53 The retraction of a controversial COVID study that promoted unproven treatment A much-critiqued study demonstrating the now-disproven idea that hydroxychloroquine can treat COVID-19 has been retracted — more than four-and-a-half years after it was published. Nature: Controversial COVID study that promoted unproven treatment retracted after four-year saga 09:10 The skin’s unexpected immune system Researchers have discovered that healthy skin — once thought to be a passive barrier — can actually produce antibodies that fight off infections. It’s hoped that the finding could one day lead to the development of needle-free vaccines that can be applied to the skin. Nature: The skin’s ‘surprise’ power: it has its very own immune system 13:02 Researchers fear Europa’s icy crust may be much thicker than thought New estimates, based on data collected by NASA’s Juno spacecraft, suggest that the ice on the surface of Jupiter’s moon Europa may be significantly thicker than previously thought. If these estimates prove accurate it could reduce the chances of Europa being habitable for extraterrestrial life. Science: Surprisingly thick ice on Jupiter’s moon Europa complicates hunt for life 20:11 Modelling the running prowess of our ancient relatives 3D computer simulations of Australopithecus afarensis — an ancient hominin that lived more than three million years ago — reveals that while our relatives could run on two legs, they likely did so at a far slower pace than modern humans. Nature: Humans evolved for distance running — but ancestor ‘Lucy’ didn’t go far or fast Subscribe to Nature Briefing, an unmissable daily round-up of science news, opinion and analysis free in your inbox every weekday. Hosted on Acast. See acast.com/privacy for more information.