Why do some people have only boy babies?

How do atoms change inside stars? How did Felix Baumgartner accelerate to over 800 miles per hour? What is inside a black hole? What decides the sex of a baby? What causes jetlag? Could we use the movement of seawater inside the Earth's magnetic field to make electricity? Why is the sea salty? Plus, are women born to flirt? Dr Chris has the answers... Like this podcast? Please help us by supporting the Naked Scientists