Coloration and color vision covary with lighting in many taxa. Determining the mechanisms underlying these patterns is difficult because lighting environments can have multiple effects on signaling that occur at multiple timescales. Lighting environments can (1) immediately affect signal propagation and transmission, which determine the radiance spectrum reaching the receiver; (2) induce variation in visual systems via developmental plasticity; and (3) lead to genetic differences in visual systems due to a history of selection in different habitats. We tease apart these effects on pecking preference and examine the relationship between pecking preference and opsin expression. Using killifish from two visually distinct populations (clear vs. tea-stained water), we performed crosses (genetics), raised animals under different lighting conditions (developmental plasticity), and assayed the preference to peck at different-colored dots under different lighting conditions (immediate effects). Pecks are interpreted as foraging preference. Developmental plasticity affected both pecking preference and opsin expression. Lighting environments also had immediate effects on pecking preference, but these depended on the lighting conditions animals experienced during development. Genetic effects were detected in opsin expression, but there were no corresponding effects on pecking preference. Overall, only 3.36% of the variation in pecking preference was accounted for by opsin expression.

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To understand the effects of habitat selection, we analyzed differences in abundance, age structure, and nesting success of black‐capped vireos (Vireo atricapilla) in 2 early successional habitat types found on Fort Hood, a 87,890‐ha Military Reservation in central Texas, USA. These habitats were 1) large areas of continuously shrubby vegetation (both natural and mechanically made), referred to as shrubland habitat, and 2) anthropogenically created small patches of shrubby vegetation centered on one or several large trees, known locally as donut habitat. The objectives of our study were to determine whether there were differences in abundance, age structure, and daily nest survival in these 2 habitat types and to determine whether donut habitat is high‐ or low‐quality habitat. Donut habitat had a lower abundance of vireos (half as many as shrubland/point count) and a higher percentage of second‐year males, suggesting donut habitat was lower‐quality habitat than shrubland. Analyses of daily nest survival indicated that habitat, nest height, and year were all important variables. Nests initiated in 2004, located in shrubland habitats, and higher from the ground were more likely to succeed. Our study provided evidence that habitat is a limiting factor for this federally endangered species. Because habitat is limiting, wildlife biologists at Fort Hood should focus on managing higher quality, contiguous shrubland habitat. Wildlife biologists should also continue to monitor areas of donut habitat to determine whether they represent potential population sinks.