LEAVES FALLING
Step-by-step explanation
~ Cliché as it may sound, leaves falling from a tree is caused by the gravity of the Earth.
GRAVITY
~ Gravity is one of the reason and the driving force that made the universe possible. It is the entity that enables the sun to hold planets together in the solar system; the reason why Earth is revolving around the sun just like the moon orbiting the Earth.
~ Gravity has to do with everything on Earth -- leaf falling from the tree, ball bouncing up and down, ocean waves, and stalactites facing downwards.
Picture showing the gravitational relationship of Moon and Earth.