Why doesn't our own snoring wake us up?

Why do some animals sleep standing up? And do fish sleep? Why are elderly voices higher pitched than younger voices? Why does the outside temperature drop just before the sunrise? Why do I feel pain in my ears during a plane takeoff, and why does chewing gum help? Do cats and dogs recognise their siblings? Why is yawning contagious? Do dogs get depressed? And why doesn't our own snoring wake us up? Dr Chris and Abongile Nzelenzele have the answers... Like this podcast? Please help us by supporting the Naked Scientists