Scientists are studying killer whales in an effort to understand the mysterious biology behind the menopause - in both orcas and humans.

Scientists find a baby tooth in the fossilised faeces of an extinct shark, suggesting the animals practised filial cannibalism.

In a surprise result, eight paraplegic people regain partial movement after a one-year training program based on brain-controlled robotics.

Observers are looking forward to an annual astronomical event that could to turn into a spectacular "meteor storm" in the early hours of Friday.