  We investigate the evolution of clustering structure through the momentum
distributions in the $^{8-10}$Be isotopes. The nucleon dynamics within the
inter-cluster antisymmetrization are discussed via the momentum distribution of
a Brink type $\alpha$-$\alpha$ wave function. For the state with a small
$\alpha$-$\alpha$ distance, we observe a significant depression with a dip
structure at zero-momentum and an enhanced tail at relatively higher momentum
region. In addition, we find the "cluster structure" in the intrinsic frame of
momentum space, which is complementary to its significant $\alpha$-cluster
dissolution in the coordinate space because of the strong antisymmetrization.
For the physical $^{8-10}$Be isotopes, the Tohsaki-Horiuchi-Schuck-R{\"o}pke
(THSR) wave functions are adopted. The evolution from the dilute clustering
state to the compact one is demonstrated by a successive depression at the
zero-momentum of nucleon distribution for the two $\alpha$-clusters within
$^{8-10}$Be isotopes. For the compact $^{10}$Be nucleus, the momentum
distribution of all nucleons shows significant depression at zero-momentum with
a dip structure, which is found to be contributed by both the inter-cluster
antisymmetrization and the $p$-orbit occupation of the valence neutrons. This
study proposes a new window for the investigations of the $\alpha$-clustering
effects via the low-momentum components of nuclei, which is expected to be
extended to the heavier nuclear clustering states.
