Aquascope Facts
Cliff and rocky beach ecology

Larvae distribution can complicate colonization

The rough periwinkle and the amphibious rock lice are examples of organisms that do not produce large numbers of embryoes, but can nevertheless have the ability to establish themselves well in remote areas. One difficulty with larval distribution is that they quickly became sparcely distributed in the water. If a larva arrives at a remote location without kin, there is a large chance that it will not find anyone to mate with when it becames sexually mature and thereby cannot result in a population increase and colonization.
    Occasionally, a fertilized female can drift into a new area and all of her young can be the new population. The problem is that if the larvae have to develope in the water over a period of several weeks, they run the risk of becaming dispersed and disappearing from the area. This is not the situation when the embryo develope within the mother until the time they are ready to start their own life on the beach. If for example a fertilized female periwinkle comes to an area where other periwinkles are absent, there is nevertheless a good chance that the periwinkle population will increase. She, the female periwinkle can have several hundred embryo within her shell and nearly all of the young she gives birth to will stay in the same area. Here, they can mate with each other and if the environment is favourable they can build a sizable population.
    Many colony building animals can effectively spread over large areas by means of fragmentation.

Organisms effect on each other

Organisms can effect each other by trying to exploit the same resources, by eating each other and by building and forming environments for each other.
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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