To do this, they used Tubifex worms, which they got drunk on ethanol. For the sake of the experiment, the worms represented these kinds of particles. The researchers were able to sort the worms by ...

this is the phylum that includes the segmented worms such as earthworms, tubifex worms, and leeches. They look like thin, pointy, white-brown strings that wiggle through the water and between pebbles.