Fact 1: Biodiversity generally increases from the poles to the equator.

Fact 2: Biodiversity, on the whole, increases towards the equator and decreases towards the poles.

Given the two facts above, answer the question "What does biodiversity do towards the poles?" with the following options: 
- moves
 - decreases
 - gains
 - survive
 - increases
 - migrate
 - It expands
 - varies


 

  decreases       