Comment by dundarious
6 hours ago
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.
They swabbed them and sequenced their DNA.
That just moves the question to how they figured out the genetic sex determination system of eels, or even how they figured out that sex is genetically determined in eels (and is it? many vertebrates don't have genetically determined sex).
Thank you, I forgot that's cheap enough these days.