Star Trek: 10 Huge Discoveries That No One Cared About

In Star Trek IV: The Voyage Home, we learn that humans were not the first life on Earth to make contact with aliens. Earth's whales had been communicating across the universe with alien life using their whale songs before going extinct due to hunting. Unfortunately, even after Kirk and the crew bring the whales back to their time, we never learn why these aliens were so interested in them.

For a long time the closest we get to some follow-up on this came from the Next Generation Enterprise-D blueprints which showed multiple two-deck high water tanks in the middle of the saucer section labelled "cetacean navigation lab" (cetacean being a word to describe whales and dolphins). This suggested that whales and other cetaceans now worked alongside humans in the time of The Next Generation and assisted in navigation in their own specialized habitats.

Finally, to the applause of many die-hard fans, the Lower Decks episode Second Contact mentions cetacean ops by name as one of the greatest parts of the ship, at last solidifying it in canon!

Still, you would think that if most starships in the federation had several two-story water tanks in them, filled with whales, we'd probably see them by now...