Chalk is created from the skeletons of ancient ocean and sea creatures.

There is a jellyfish called the Turritopsis nutricula which can turn back to a young jellyfish after is becomes a adult

                      Tasmanian Devils sometimes sneeze to challenge an opponent to a fight.

                                                       
                                           The 'OK' symbol means 'pay me' in Japan.

                                 Some musicians that have amnesia still remember how to play an instrument.

                                                                        A black hole could weight as much as 10 billion suns.

                                                                      Pumice is the only rock that can float.