The song sparrow occupies several microhabitats (Aldrich 1984), whereas the chipping sparrow and red-winged blackbird occur in the same basic habitat throughout their ranges (AOU 1983).
Red-winged blackbird (18) 0.030 10, 11 Chipping sparrow (7) 0.036 12 Song sparrow (34) 0.026 13, 5 Tufted titmouse (2) 0.038 9 Black-crested titmouse (3) 0.050 9
For example, the most divergent chipping sparrow haplotypes are 0.6%, whereas this species differs by 3.6% sequence divergence from its nearest extant relative.
These five species might have been historically codistributed and responded to events idiosyncratically (fox sparrow and Canada goose) or not at all (red-winged blackbird, chipping sparrow, song sparrow), or were simply not historically codistributed.
For example, one might predict lower levels of dispersal for the song sparrow (34 subspecies) than the chipping sparrow (seven subspecies), but such was not the case.
The two subspecies groups of the plain titmouse, two samples of the mountain chickadee, brown-headed cowbird, and the megarhyncha and schistacea groups of the fox sparrow, exhibit extensive mtDNA differentiation between coastal and interior populations, whereas these east-west splits are not evident in the mourning dove, downy woodpecker, song sparrow, and chipping sparrow. Possibly, the minor southwestern differentiation in the red-winged blackbird and northern flicker is coincident with this general pattern.
Population structure and gene flow in the chipping sparrow and a hypothesis for evolution in the genus Spizella.
Among species, detection on repeated surveys was significantly greater in 2007 than in 2008 for Lucy's warblers, western tanagers, chipping sparrows, and lark buntings, and it was significantly greater in 2008 for lark sparrows (Table 1).
Habitats selected at a significantly higher rate than at least one other habitat included grasslands by five species (western kingbirds, chipping and lark sparrows, and lark and lazuli buntings), willow riparian by four species (Lucy's warblers, lark and lazuli buntings, and lesser goldfinches), mesquite by four species (ash-throated flycatchers, Lucy's warblers, lark sparrows, and lazuli buntings), cottonwood riparian by three species (Lucy's warblers, lazuli buntings, and lesser goldfinches), oak by two species (chipping sparrows and black-headed grosbeaks), and desert scrub by one species (lazuli buntings).