1. Around 1900 the first dams were built on the Muskegon river, and this immediately cause a problem in the ecosystem by being a blockade for the movement of the water species, as well as causing higher mortality by killing them in the turbines.
2. By 1950 more dams were built, and the there were even more blockades on the way of the water species, so their movement was restricted even more, the mortality rates skyrocketed because of the disposing of the oxygen, temperature change, river flows changing etc.
3. Even though the scientists miss information from the period before the dams were built, since the information have started to be gathered it has been very obvious that the main factor for ruining the ecosystems on the Muskegon river are the dams by causing all sorts of changes in the water.
That is know as the Kuiper Belt.
Is there a picture that is supposed to be attached?
<u>Answer:</u>
<u>The Continental drift</u> is the displacement of continental masses relative to each other. This hypothesis was developed in 1912 by Alfred Wegener, who affirmed <u>that thousands of years ago there was a single and unique supercontinent, called </u><u>Pangea</u><u>, which later became separated.
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His formulations were based mainly on the way in which the forms of the continents seem to fit on each side of the Atlantic Ocean, such as Africa and South America. He also took into account the distribution of certain fossils that coincided in continents far from each other.
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At first this approach was discarded by most of his colleagues, because <u>
his theory lacked a logical and geological explanation for its epoch. </u></h2><h2>
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He proposed that the continents move on another denser layer of the Earth that made up the ocean floor. But it was not until the 1960s, with the development of the theory of tectonic plates, that the movement of the continents could be adequately explained.
