There are some truly weird creatures in this world, from bizarre animals that look like Frankenstein projects to legitimately ...

At first glance, the lettuce sea slug (Elysia crispata) looks like a leafy underwater alien. But what’s hiding inside its frilly green body is far more fascinating than its salad-like appearance.

Scientists caught a “transparent” sea creature with horn-like appendages off of Mexico and discovered a new species, a study said. Getty Images Off the western coast of Mexico, a “transparent” sea ...