David Joseph Horn

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Several grassland bird species have been shown to be area sensitive. This area sensitivity occurs when a species' frequency of occurrence, or relative abundance, tends to be lower in smaller fields. The detection of area sensitivity, however, is not consistent among studies because a species may exhibit area sensitivity in one study, but not in another. We(More)
Ant attendance is known to affect the population dynamics of aphids and may increase or decrease aphid populations through stimulation, predation, or protection. In this study, we performed a series of laboratory experiments to examine the effects of ant attendance on populations of the soybean aphid Aphis glycines. Aphid colonies were exposed to the(More)
A list of microlepidoptera belonging to the superfamily Gelechioidea was produced from June trap samples from sites within the Wayne National Forest (Lawrence County), an Appalachian forest in Southern Ohio that was once a greatly disturbed area and has since re-established over a period of nearly 100 years. The composition and diversity of Lawrence county(More)
Among the most popular reasons that people feed wild birds is that they want to help birds. The extent to which supplemental food helps birds, however, is not well established. From spring 2011 to spring 2014, we examined how feeding of wild birds influences the health of individual birds at forested sites in central Illinois, USA. Specifically, we compared(More)
Sulforaphane is a natural product found in broccoli, which is known to exert many different molecular effects in the cell, including inhibition of histone deacetylase (HDAC) enzymes. Here, we examine for the first time the potential for sulforaphane to inhibit HDACs in HaCaT keratinocytes and compare our results with those found using HCT116 colon cancer(More)
During the breeding seasons of 1990-1992 and 1994, we examined how habitat characteristics surrounding nestboxes influenced nesting success of eastern bluebirds (Sialia sialis} and nesting attempts by tree swallows (Tachycineta bicolor^), house wrens (Troglodytes aedon), bluebirds, house sparrows (Passer domesticus), and deer mice (Peromyscus spp.). Using(More)
Philornis downsi (Dodge and Aitken) is a bird-parasitic muscid fly native to mainland South America that recently invaded the Galápagos Islands where it is parasitizing Darwin’s finches and other land birds. This parasite was previously known only from Argentina, Brazil, and Trinidad and Tobago. The first report of P. downsi from mainland Ecuador is(More)