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Good evening, ladies and gentlemen. I'd like to start by explaining that the purpose of our latest expedition to South America was not originally to study habits loss. As some of you may know, a few years ago I published a book about the wildlife of the Amazon after having travelled extensively in the region.
The purpose of our latest trip was to follow up on the work I had done before. As time went on, however, I realised, to my horror, that a number of the places I'd visited the first time were no longer tropical rainforests. The trees had been cut down, so they simply lay bare, because the rain had :washed away" the thin layer of the topsoil day by day and made the land completely useless.
The speaker organised his latest expedition to the Amazon to ………... .