• How many kinds of rodent are there?
  There are more than 1,600 different species of rodent, including ...

• Why do rodents get long in the tooth?
  The two sharp teeth at the front of the rodent's jaw-called ...

• Which is the biggest rodent?
  The largest rodent in the world is the capybara, which lives in South ...

• Do dormice really sleep a lot?
  Dormice do sleep through the winter. This hibernation may start in ...

• Where do porcupines live?
  There are two groups of porcupines. New World porcupines live in ...

• What was there before the universe?
  No one has a clue. Some people think there was an unimaginable ocean ...

• Why is the universe getting bigger?
  We can tell the universe is getting bigger because every galaxy is ...

• What was the Big Bang?
  In the beginning, all the universe was squeezed into an unimaginably ...

• How do we know what it was like?
  We know partly by mathematical calculations, and partly by ...

• How long will the universe last?
  It depends how much matter it contains. If there is more than the ...