Aquascope Facts


Beach living mussels can act as another example. We suppose that you can recognize two species by their siphons sticking out of the sediment when they are dug down into the sand bottom. When you and your friend have visited different beaches you have noticed the following: When there are many individuals of one species, that we call A, there are few individuals of the other, that we will call B. When you point this out to your friend, he replies that he knows why. He says that it is because the mussels compete with each other and that there are not adequate resources, e.g. space or food, for both species to coexist.

To observe and reflect is not enough

Your friend has offered you a model that explains why certain mussels are common and others are uncommon within a certain area. You now have an observation (what you saw) and an explanation (reasons for what you saw). With the help of good observation and reasoning talents we have completed the first two steps in a scientific research process, but just these two steps are not enough.
    Imagine now that you don't think the reason for the presence of the two species of mussels has to do with competion you reply that: ”It is not always competition that is the reason for why different types of mussels are found in different areas. The explanation is that one species thrives better in really salty water, while the other prefers more brackish water.”
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Bo Johannesson | Martin Larsvik | Lars-Ove Loo | Helena Samuelsson