Fact 1: Macroevolution is evolution over geologic time above the level of the species.

Fact 2: Geologic time lines are expressed in geologic eras and periods.

Given the two facts above, answer the question "macroevolution is evolution over what, above the level of the species?" with the following options: 
- plants
 - H 2 O
 - years
 - scale
 - gravity
 - eras
 - weathering
 - Joules


 

      eras   