Video clips
Vorticella 1
Play video:
Zoothamnium - Big colony of geneticly identical
animals (top view), fastened to the main stem by small contractile pedicles.
When there are vibrations the whole colony contract swiftly to a "ball" and unfold
like a blossom when the danger is over.
Vorticella 2
Play video:
Zoothamnium - Details of a colony. Tiny heads with
whirling cilia.
The curled myonema (contractile protein fibrils) inside the pedicle are clearly
visible. In a sense they are to be muscle fibres.
Vorticella 3
Play video:
Zoothamnium - If irritated the heads are jerked out of the dangerous area Žby contracting its myonema. Re-extension is performed by extremely thin fibrils in a much slower movement.