Crabs feel pain

You cannot ask an animal if they feel pain.  Most people accept that higher animals, the vertebrates, feel pain in the same way as we do.  We all recognise when our cat or dog is hurt.  But what about invertebrates, like crustaceans, such as crabs, prawns or lobsters?  There has been a long belief that they only show a flinch reflex, or nociceptive response, to a painful stimulus.  But new research adds weight to the argument that crustaceans do feel pain like we do, because they can learn to avoid future painful experiences after being given an electric shock. (Photo: Professor Bob Elwood)

Another Earth orbiting NASA satellite is in the news this week. This one looks out into space.  It houses the Fermi telescope, which has been scanning the whole cosmos since 2008, catching sight of the highest-energy light we know of - gamma rays.  These come from the most energetic and exotic corners of the Universe: supernova leftovers, the flashing neutron stars called pulsars, even the jets from black holes.  But this week, there's more hope that the Fermi telescope might be able to pin down one of the biggest mysteries in astrophysics: the mysterious stuff called dark matter. (Photo: Fermi 3-year all-sky map / NASA)