It’s hard to believe we’ve only cataloged around 15% of animal species — so much of life on Earth is still out there, undescribed and unseen. And the ocean makes it even wilder: roughly 75% of the seafloor hasn’t been mapped, and we’ve explored only about 5% of the total ocean volume. There’s a lot of world left to find.
Even after centuries of effort, some 86 percent of Earth’s species have yet to be fully described, according to a new study that predicts our planet is home to 8.7 million species.