Hydra are animals in the phylum cnidaria which includes jellyfish, sea anemones and corals. They are found in freshwater environments all over the world.
Hydra tentacles contain special cells called cnidocytes, which house a stinging structure known as nematocysts. Nematocysts snare and inject a toxin into the hydra's prey, which leaves them paralyzed and defenseless against the hydra.
At 2:51, you can see the hydra using its tentacles to catch some daphnia. However, They were too large to be eaten.
Hydra can divide asexually by budding, in which a mini-hydra clone forms a bud from the bottom of the hydra and separates when it matures. Hydra also have amazing regenerative abilities and can grow back after being cut in half!
The magnification of each shot is shown in the bottom right hand corner.
