Sprinting Neanderthals, Geodynamo, Spreading Sneezes and Dying Hares

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Manage episode 226340629 series 1301268
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Many physical features of Neanderthals might not be for cold climate adaptation as previously thought. They may be for types of locomotion. Which, according to paleo-ecologist, John Stewart at Bournemouth University, makes the long thigh to calf ratios more likely that Neanderthals were adapted to fast, powerful sprints, as part of their hunting and survival. The clues to this lie less in the bones and more in the evidence that Neanderthals lived in wooded areas rather than tundra. Earth’s solid iron inner core, liquid outer core and interactions between the two give us our protective magnetic field and are responsible for the ‘geodynamo’ that drives this, as well as volcanism and Earth’s tectonics. But we don’t yet know when the solid core formed. It’s hard to find paleo-magnetic records from early in Earth’s history. But now a group at Rochester University in New York have discovered magnetic particles from 565 million year old Ediacaran Period rocks in Canada and they say that at the time lots of life was evolving on our planet, the geodynamo was low and wobbly. This leads them to believe the solid core formed two to three times later than previously thought. A typical sneeze will throw out 40,000 tiny droplets loaded with viruses or bacteria, which can hang in the air like a cloud until someone else comes along and inhales some. To a scientist, this suspension is an aerosol, and what goes on inside a tiny droplet can be very different from what happens in a beaker of fluid. But studying those conditions, which can alter whether a germ can survive its aerial journey is hard. Which is why at Bristol University they’ve developed an aerosol trap that can hold droplets mid-air, without contact, with an electric field. Rabbits and hares across Europe have been declining rapidly over the past few decades. There are a number of factors involved (Agricultural intensification, climate change, hunting and a whole host of infectious diseases.) Myxomatosis in rabbits, which has now jumped into hares, is fairly well known by the public, but there are other viral and bacterial diseases that are jumping between the species and the most recent one Rabbit Hemorrhagic Disease Virus 2 (RHDV2) is of particular concern right now. Very little is known about this disease in wild populations. It was seen in hares in Europe a few years back, but it’s now just been identified in the UKs native brown hare population. Biologist Diana Bell at the University of East Anglia wants the public to contact her if they see any hares that look like they’ve died from the disease. Producer - Fiona Roberts

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