There are nettles, and there are false nettles that look very similar to nettles when not in flower. Given that the plants can’t see each other to imitate, how did the false (non-harmful) plant develop to be so visually similar to the harmful one?
In: Biology
It’s just classic mimicry. Any organism may develop a specific shape altering phenotype due to random mutations, if the phenotype gets it closer to a shape where the probability of it getting attacked is reduced, the mutation persists in the gene pool. Over time the phenotype gets refined and refined until it looks intentional. If this organism happens to reside in a region where another organism is avoided by predators, then a mutation that gets it to look similar to that organism will increase its fitness. And so it eventually mimics it. It’s still random chance, but the selective pressure is not random, and it’s skewed to favor the shape of this other organism, which is why the organism may evolve towards it.
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