  We investigate the locomotion of thin, living \textit{T.~Tubifex} worms,
which display active polymerlike behavior, within quasi-2D arrays of pillars
with different spatial arrangements and densities. These active worms spread in
crowded environments, with a dynamics dependent on both the concentration and
arrangement of obstacles. In contrast to passive polymers, our results reveal
that in disordered configurations, increasing the pillar density enhances the
long-time diffusion of our active polymer-like worms, while we observe the
opposite trend in ordered pillar arrays. We found that in disordered media,
living worms reptate through available curvilinear tubes, whereas they become
trapped within pores of ordered media. Intriguingly, we show that reducing the
worm's activity significantly boosts its spread, enabling passive sorting of
worms by activity level. Our experimental observations are corroborated through
simulations of the tangentially-driven polymer model.
