Giraffes are the world's highest land animal. A male giraffe can grow up to 5.5 meters high and the neck alone can be 2.4 meters long. It is believed that giraffes have become so high, because it has been an advantage to be able to reach food that only a few animals have been able to reach. This is the reason why the highest giraffes over time have been able to survive periods of limited food, while the lower ones have had to succumb. Over many generations, the giraffe has become taller.