Aquascope Facts
Cliff and rocky beach ecology It is not only heat regulation that is important for survival, waves and predators are also of interest. Therefore, it is not always the large round white organisms that survive and the most common on the beach.
    An effective way of losing heat is to let water evaporate, but this also can dehydrate the organism. Certain organisms collect so much water as possible between their shell and body before they are left stranded at low tide. Barnacles do this, so they are able to give off heat by means of evaporation.

To breath air

Most animals that inhabit the shoreline have gills that enable them to breath in water. Gills are outgrowths of the body that are heavily creased, thin walled and greatly branched. This gives them a very large area for an effective gas exchange between the body and the surrounding water, but this construction can also result in dehydration if they come in contact with the air. For this reason, most beach organisms have their respiratory organs contained within a body cavity. Here, the gills are well protected from the environment and their surfaces are easily kept moist without too great a water loss. With mussels and shellfish, the protective cavity is composed of a skin like casing known as the mantle. Outside the mantle is the shell that gives further protection. Barnacles also have a type of mantle and it is the mantle wall which is furnished with blood vessels and functions as the respiratory organ.
    To conserve water at low tide, certain mussels, shellfish and barnacles must enclose themselves totally within their shells. At such times they can enter a trance state, where they do not even need oxygen from the surrounding water.
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Cliffs and rocks are fantastic!
Zoning and flecked occurrence
Animals that are attached
Modular construction
Variation and change
Variations in water level
Wave exposure
Both cliffs and rocks
Freshwater and saltwater
Geography, climate and history
Organisms life cycles
Organisms effect on each other
Energy and the flow of material

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Bo Johannesson | Martin Larsvik | Lars-Ove Loo | Helena Samuelsson