The peregrine falcon (Falco peregrinus) and the saker (Falco cherrug) have been sequenced. They appear to be closer to songbirds than other raptors. The chicken and the turkey comprise one evolutionary branch, and the zebra finch and the two falcon species form a second. Falcons had fewer intact olfactory receptor genes thaqn zebra finches, even though they have a larger olfactory bulb ratio: researchers previously thought that these two traits were positively correlated. The most recent common ancestor of peregrines and sakers was dated to 2.1 million years ago. The two species had more than 99.6% of their genomes in common. Sakers unlike peregromes, primarily inhabit and enviro nments. The researches found that the saker falcons have more copies of genes involved in water conservation and the inhibition of sodium uptake than the peregrine, suggesting a genetic basis by which this species copes with the desert habitat.
Info from Lab Animal, 42(5): May 2013 pg 155