SAT Subject Biology Practice Question 40: Answer and Explanation
4. Question below refers to the phylogenetic tree of fly families shown.
According to the phylogenetic tree, which speciation event occurred EARLIEST?
A. The event leading to Muscoidea and Oestroidea
B. The event leading to Oestroidea and Acalyptratae
C. The event leading to Syrphoidea and Hippoboscoidea
D. The event leading to Acalyptratae and Hippoboscoidea
E. The event leading to Muscoidea and Acalyptratae
Correct Answer: C
The branches leading to Syrphoidea and Hippoboscoidea diverged from a common ancestor farthest back in time, indicating that this speciation event occurred earliest.