What is a "fitness surface"?

Question

I found this term in a paper that I'm editing and I really should know what it means so I'd rather not ask the author. Thanks in advance.

Answer 1

A "fitness surface" is a graph of the average fitness of a population in relation to the frequencies of genotypes in it.  Peaks on the landscape correspond to genotypic frequencies at which the average fitness is high, valleys correspond to genotypic frequencies at which the average fitness is low.  It is more commonly called “adaptive topography” I Hope that that makes sense for the context that it is in for the paper that you are editing.

Answer 2

a gym floor