(a) Research natural area means an area that is established and maintained for the primary purpose of research and education because the land has one or more of the following characteristics:

(1) A typical representation of a common plant or animal association;

(2) An unusual plant or animal association;

(3) A threatened or endangered plant or animal species;

(4) A typical representation of common geologic, soil, or water features; or

(5) Outstanding or unusual geologic, soil, or water features.

(b) [Reserved]