Europe is not a typically dry place (unlike for exampe Mesopotamia) so it does not need rivers for irrigation.
Instead, rivers are needed more for transport - they have served as a means of communication and for the exchange of goods.
For example, Danube allowed a big-scale trade between the cities lying on it: Vienna, Budapest and Bratislava.
<span>I think life in small Caribbean islands, such as Aruba and Bonaire, might differ from larger South American countries, such as Argentina and Brazil, in various ways. First of all, if they don't have a source of water, they are dependent on external source, which can limit the option of what is available. Moreover, they could experience a shortage of food, for the same reason as water. There's also the problem of space, too many people could easily disrupt the ecosystem in a small island.
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Because the dimension of the island and the natural resources are completely different from the one from a big country with a lot of places that can supply an unexpected shortage. Moreover, on a small island, the space and the characteristics of the place makes things a little more complicated than in a continental country.</span>
