Genomic Evidence for Rare Hybridization and Large Demographic Changes in the Evolutionary Histories of Four North American Dove Species

Introductions and invasions provide opportunities for interaction and hybridization between colonists and closely related native species. We investigate this phenomenon using the mitochondrial DNA COI and 81,416 base-pairs of overlapping nuclear variation to examine the evolutionary histories and signatures of hybridization among introduced feral Rock Pigeon and Eurasian Collared-Dove and native White-winged and Mourning doves in southwestern North America. First, we report all four species to be highly divergent across loci (overall pair-wise species ΦST range = 0.17–0.70) and provide little evidence for gene flow at evolutionary timescales. Despite this, evidence from multiple population genetics analyses supports the presence of six putative contemporary late-stage hybrids among the 182 sampled individuals. These putative hybrids contain various ancestry combinations, but all involve the most populous species, the Mourning Dove. Next, we use a novel method to reconstruct demographic changes through time using partial genome sequence data. We identify recent, species-specific fluctuations in population size that are likely associated with changing environments since the Miocene and suggest that these fluctuations have influenced the genetic diversity of each dove species in ways that may impact their future persistence. Finally, we discuss the importance of using multiple marker types when attempting to infer complex evolutionary histories and propose important considerations when analyzing populations that were recently established or of domestic origins.

Dovesong

This chapter describes the mourning dove's funerary dirge. For the first time in nearly a century, open season has been declared on the dove. Amendments fail to outlaw the lead bullet or set the kill zone back from homes. The chief executive signs the bill in the company of lobbyists from the National Rifle Association. These five ounces of meat with wings are purported to bring seven million dollars into governmental coffers. Ultimately, forty-one of fifty states favor open season on the dove of mourning, making them, in effect, sitting ducks. The chapter then explores how the debate over open season on the mourning dove heralds the coming of the culture wars.

Human-dominated land cover corresponds to spatial variation in Mourning Dove (Zenaida macroura) reproductive output across the United States

Studies examining impacts of land cover typically focus on abundance, distribution, and/or community richness, overlooking underlying demographic processes such as survival or reproduction. Here, we present findings from a unique dataset that allowed us to measure the relationship between land cover and reproductive output across the distribution of the Mourning Dove (Zenaida macroura). We used hunter-derived, Mourning Dove wing data across 1,271 counties in the United States from 2008 to 2014 to estimate spatially explicit age ratios (juveniles: adults), an index of local reproductive output. We also used raster imagery data to estimate relationships between reproductive output and land cover and crop cover. We found that low reproductive output occurs in regions where Mourning Dove declines have been steepest. Our findings reveal that impacts of land cover vary geographically, but even at a coarse resolution, small changes in the relative proportion of human-dominated landscapes can have a significant impact on the reproductive output of this generalist species. Maize and soybean systems correlate with up to a 57% reduction in Mourning Dove reproductive output in the eastern United States. In the western United States, developed areas correlate with a 41% increase in reproductive output. Across the United States, native habitats had neutral or negative relationships with age ratios. Our study contributes continental-scale evidence that Mourning Dove reproductive output is largely driven by human-dominated land cover including agricultural and residential areas. With Mourning Doves declining across the range, discerning more fine-scale land cover factors is critical for ensuring Mourning Dove populations persist into the future.

Racial Realism

Realism as it has been articulated by white, middle-class literary gatekeepers since its heyday in the early twentieth century (and frequently into the present) has failed to address racism and imperialism of the era. Gene Jarrett describes black authors developing new literary forms in order “to re-create a lived or living world according to prevailing ideologies of race or racial difference.” This chapter expands Jarrett’s definition of “racial realism” beyond the black-white binary in order to show how writers of color from a variety of backgrounds crafted their own versions of realism, deploying allegory and making strategic use of stock genres such as the oriental romance and the western. For white readers in particular, these seemingly “nonrealist” plot elements provided intellectual distance from the contemporary injustices of racism in the age of US imperialism. However, for in-group readers, racial realism functioned both literally and figuratively to highlight experiences of racism and to legitimize histories too often ignored, misunderstood, or misrepresented in mainstream literary realism. Writers such as Winnifred Eaton and Mourning Dove created their own texts that were shaped by multiple literary ancestors and spoke simultaneously, though distinctly, to white readers and to their own communities of color.

Revisiting Effects of Hunting on Mourning Dove Nest Survival

We reconstructed a historical dataset from a national mourning dove Zenaida macroura nesting study evaluating the effects of hunting on nesting birds during the September portion of the hunting season using Bayesian hierarchical models; the reconstructed dataset contained 707 nests. The original nest survival estimate of 96.3% (nonhunted zones) fell within the range of our average daily nest survival rates and credible intervals (CI) of 97.2% (95% CI: 96.2–98.0%) for nonhunted, but the original nest survival estimate of 95.5% (hunted zones) was lower than our average daily nest survival rates of 96.9% (95% CI: 96.1–97.7%) for hunted zones. Similarly, overall nest survival for areas and years combined for hunted zones was 44.3% (95% CI: 35.3%, 53.9%) and 48.1% (95% CI: 36.9%, 59.8%) for nonhunted zones. The most parsimonious model contained the primary covariates of hunted or nonhunted status (hunted or paired hunted) or paired hunted or nonhunted nest searching plot (zone), and year. We observed lower nest survival for the hunted or delayed-hunt zones compared to the zones with hunted or nonhunted season structure. Regional differences may be explained by states with early and late hunting seasons separated by ≥ 21 d compared to other pairs where hunted and nonhunted areas occurred simultaneously. Our reanalysis provides managers additional assurance that the basic premise of limited or no effect of harvest on mourning dove populations is still valid but continued monitoring of population status is warranted.