Tube feet attach in marine environment: echinoderms
 

The tube feet of echinoderms attach to surfaces via suction adhesion.

     
  "Besides mollusks, echinoderm tube feet make use of suction adhesion, as do a wide variety of other aquatic systems--either as the only attachment mechanism or in combination with others. Among terrestrial systems one thinks first of wet ones--frogs for instance. But the mechanism finds use even in arboreal mammals." (Vogel 2003:427)
  Learn more about this functional adaptation.