Batteries are fishy

So according to a book I read called Dark Light by Linda Simon, when Alessandro Volta read about the electric organs of torpedo fish (pictured above) back in the 18th century, he decided to try to imitate the organ with metals.

That resulted in this: the voltaic pile, which according to some sources was the very first battery.

So, if the battery is an imitation of a fish organ and transistors are imitations of neurons (or synapses), what other technological innovations can we trace to organic blueprints?