List perpetually under construction, here's some organisms I think are really cool ^u^

(I won't cite Wikipedia on principle but feel free to go on there to look at more info about these species lol)

Micromalthus debilis: the beetle species that only becomes an adult when exposed to heat

Aphids that are born pregnant

Salamanders (females from a 6 million year old lineage in the Ambystoma genus) that steal genes from males of several different species in the same genus

Rotifers, tiny aquatic organisms that also steal genes, but this time it's from whatever they want

All manner of parasitic crustaceans (this is just some of them)

Bobbit worms

Female fireflies in the genus Photuris mimic the flash patterns of females of other firefly species and eat the males they attract