Aquascope Facts

Two opinions

You suggest a totally different model as a possible explanation for your observations and maintain that the two species exist in different environments because of differences in salinity. One species needs a higher salinity, otherwise its body tissues absorb too much water, swell up and become damaged, while the other species prefers a lower salt content or it will loose too much water to the more salty environment. The presence of one of the species does therefore not influence the survival of the other.
    Your explanation is as good as your friends in one major respect. Both opinions explain why the different species dominate in different areas. Both models also make a viable attempt to explain the observed patterns, but the explanations as such are totally different. One explanation implies that the different species of mussels affect one another so that they don't coexist optimally. The other emphasizes environmental variations: The two species of mussels cannot grow well in the same salt concentration.


We now have a problem, we have two models that can explain what we have observed and there might even be several other possible explanations. Therefore, we really need a reasonable method that can help us decide which model is the correct one. We can use argumentation and discussion (the usual method of dealing with differences of opinion), or we can attempt a more scientific procedure.

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