  We explore scenarios in which the graviton is not a fundamental degree of
freedom at short distances but merely emerges as an effective degree of freedom
at long distances. In general, the scale of such graviton `compositeness',
Lambda_g, can only be probed by measuring gravitational forces at short
distances, which becomes increasingly difficult and eventually impossible as
the distance is reduced. Here, however, we point out that if supersymmetry is
an underlying symmetry, the gravitino can be used as an alternative probe to
place a limit on Lambda_g in a collider environment, by demonstrating that
there is a model-independent relation, Lambda_g > m_{3/2}. In other words, the
gravitino knows that gravity is standard at least down to its Compton
wavelength, so this can also be viewed as a test of general relativity possible
at very short distances. If composite gravity is found first at some Lambda_g,
this would imply a model-independent upper bound on m_{3/2}.
