There is a sure way to know that humans (engineers, and others) can do excellent designs, e.g. cars, bikes, ships, trains, aeroplanes, and more.
Most would be optimised, and hence optimal. We can design flying insects, and small birds, and these would look real and even work like real ones (at least for short ranges, in time and volume), but they are not really real; the latter can evolve only in the process of evolution.
It is high time we learn to appreciate this.
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