The Riddle - so here is one

You are on a horse, galloping at a constant speed. On your right is a sharp drop off, and on your left is an elephant thundering along at the same speed as you. Directly infront of you is a galloping kangaroo and your horse is unable to overtake it. Behind you is a lion running at the same speed as you and the kangaroo. What must you do to safely get out of this highly dangerous situation?