A Pair of Closely Related Bird Species Includes One That

Multiple Choice

A pair of closely related bird species includes one that migrates long distances over the course of months and another that has evolved near-flightlessness on its island home.What might you expect to find when comparing the breast muscles (used for flight) of these species?

A) The island species would have relatively larger amounts of red muscle.
B) The migrant species would have relatively larger amounts of red muscle.
C) The migrant species would have relatively lower levels of myoglobin.
D) The island species would have relatively higher numbers of mitochondria in each muscle cell.
E) The two species would have approximately equal amounts of fast-twitch muscle fibers.