Scientists Figured Out How Eels Reproduce (2022)

Aristotle spent serious time on this and concluded eels spontaneously generated from mud, that's not a knock on him, you genuinely cannot find reproductive organs in a wild eel because they don't develop until the final migration, it took satellite tagging in 2018 to actually confirm what was happening. A 2,300 year old mystery closed by a GPS tracker is a good reminder that some problems just had to wait for the right instrument

I remember being fascinated by animals as a kid and the mystery of where eels went was one of the big unsolved puzzles I remember hearing about.

Much more recently I heard on QI about how medieval people, not knowing about migration, believed, through a lot of leaps, that it was ok to eat barnacle geese at lent. Worth investigating if you are curious :)

In the satellite tracking experiment, I wonder how they sexed the eels to determine they were female before tagging, given the lack of primary sex organs at that time. Are there obvious secondary characteristics like size?

> The researchers behind this recent discovery used satellite tags to follow 21 female European eels as they navigated the final phase of their incredible journey southwest from the Azores, the volcanic archipelago of the North Atlantic Ocean west of Portugal.

"figured out how" seems a little strong, when:

> questions remain about the timing and navigation of the eels across thousands of kilometers of open water

Fascinating how certain animals have evolved with complex migration patterns to breeding grounds. And unfortunate that 95% of the population has already collapsed.

Makes me wonder what the world was like before this last great extinction.

The click bait version adds “and it’s electrifying”.