It's already happened. The concern is always about changes from the present state, no matter what the present state is. Once screwworms have already been eradicated from North America, there is concern about the impact of bringing them back.
replyOkay but do you think it was a bad idea at the time?
replyI think it warranted extreme caution back then just as the opposite would now. Humans made a lot of ecosystem changes in the past and the results of some of them are the reason that we think we should apply extreme caution now.
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