its rotation on a tilted axis and its nearly constant uniform distance from the sun.
Insulin.
Glucocorticoids
they form a cycle that keeps the levels of oxygen and CO2 fairly constant in earths atomospere. And their opposites but they both keep our globe spinning.
dodo
dodo
The Sun's gravity keeps the planets orbiting the Sun.
it keeps a stable environment by the sucking things on it's five points.
gravityy brew XD
it is the padding that keeps the ball stable
Inertia.
the earths gravitational pull keeps the moon in orbit
stable , i think ;P