Few animals have sparked humanity’s curiosity as much as the eel (Anguilla anguilla). Until a recent past, this slimy, slippery, snake-shaped, incredibly agile fish inhabited virtually every body of water in Europe and Northern Africa, often in mind-blowing abundances. And nobody knew where they came from.
Philosophers and naturalists from Aristotle to Linnaeus were fascinated by the eel’s apparent lack of reproduction. Sexual organs or eggs had never been observed, so scholars generated diverse and imaginative explanations for the existence of eels.
