SAT Subject Biology Practice Question 41: Answer and Explanation
5. Question below refers to the phylogenetic tree of fly families shown.
Which two families of flies share the GREATEST number of nucleotide base pair sequences?
A. Syrphoidea, Hippoboscoidea
B. Oestroidea, Hippoboscoidea
C. Muscoidea, Acalyptratae
D. Acalyptratae, Hippoboscoidea
E. Asiloidea, Acalyptratae
Correct Answer: B
The branches leading to Oestroidea and Hippoboscoidea diverged from a common ancestor most recently. Therefore, the fewest differences in DNA base pairs will have occurred between these two groups.