Elves do tend to plan ahead....
"Honey I think we should have another."
"Already? Our youngest is only 254."
"I know, but what if they stop learning how to play the same note on the piano for 5 years and become an adventurer?"
"Ah, good thinking, alright, lets get busy."
***a few weeks pass***
"Honey, I don't think it took."
"You mean we have to do it again?" *grumbles* "Stupid low fertility rates."
What if- like Dr. Zoidberg- male elves every few years would become consumed with reproductive rage...and “jelly? They’d grow larger, become more aggressive, emit a muskier scent.
You know...so they looked & smelled more like humans?
Would explain a LOT.