The insects in the order Odonata, including the dragonflies and damselflies, begin life as wingless aquatic nymphs and only later in life emerge as sexually mature, winged adults. If an evolutionary change produced a dragonfly that reached maturity while still in the aquatic stage, this would be an example of .

Pedomorphosis

Explanation:

Pedomorphosis is a type of evolutionary change that occurs when features or traits that are usually common with the juveniles or larval of an ancestral organisms, become displaced by the adult traits or features in the descendants of that organism. This can either be as a result of slowing down or the acceleration of the physiological development of the organism.

The dragon fly that is produced, which shows features of adult development at its aquatic stage, is an example of Pedomorphosis.

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