Apopulation of rabbits lives in a forest. the habitat features many small spaces for hiding. over many generations, the average size of the rabbits gets smaller and smaller. what type of selection is this?

Directional Selection

Explanation: Directional selection results in a covariance between the trait and fitness and can lead to changes in a trait in a population.

during the process of dna replication, brdu can replace thymidine and incorporate into the newly synthesized dna, cell proliferation thus can be reflected in the extent of brdu incorporation.