In a very basic sense there is a general dichotomy in the grouping of organisms on this planet as either a plant or as an animal. Myself, like most of the rest of you, belong to the animal group, but there are those organisms out there that exists on the boundary; one in particular is the sea slug, Elysia chlorotica.
![The sea slug Elysia chlorotica (Photo credit: Patrick Krug)](https://www.southernfriedscience.com/wp-content/uploads/2015/02/Elysia-2-Chlorotica-Credit-Patrick-Krug-298x300.jpg)