  We present two new dynamical tests of the biasing hypothesis. The first is
based on the amplitude and the shape of the galaxy-galaxy correlation function,
$\xi_g(r)$, where $r$ is the separation of the galaxy pair. The second test
uses the mean relative peculiar velocity for galaxy pairs, $\vs(r)$. This
quantity is a measure of the rate of growth of clustering and it is related to
the two-point correlation function for the matter density fluctuations,
$\xi(r)$. Under the assumption that galaxies trace the mass ($\xi_g = \xi$),
the expected relative velocity can be calculated directly from the observed
galaxy clustering. The above assumption can be tested by confronting the
expected $\vs$ with direct measurements from velocity-distance surveys. Both
our methods are checked against N-body experiments and then compared with the
$\xi_g(r)$ and $\vs$ estimated from the {\sc APM} galaxy survey and the Mark
III catalogue, respectively. Our results suggest that cosmological density
parameter is low, $\Omega_m \approx 0.3$, and that the {\sc APM} galaxies trace
the mass at separations $r \ga 5 \Mlu$, where $h$ is the Hubble constant in
units of 100 km s$^{-1}$Mpc. The present results agree with earlier studies,
based on comparing higher order correlations in the {\sc APM} with weakly
non-linear perturbation theory. Both approaches constrain the linear bias
factor to be within 20% of unity. If the existence of the feature we identified
in the {\sc APM} $\xi_g(r)$ -- the inflection point near $\xi_g = 1$ -- is
confirmed by more accurate surveys, we may have discovered gravity's smoking
gun: the long awaited ``shoulder'' in $\xi$, generated by gravitational
dynamics and predicted by Gott and Rees 25 years ago.
