Richard D Collins

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When traits experience directional selection, such as that imposed by sexual selection, their genetic variance is expected to diminish. Nonetheless, theory and findings from sexual selection predict and demonstrate that male traits favored by female choice retain substantial amounts of additive genetic variance. We explored this dilemma through an(More)
Males of the lesser waxmoth Achroia grisella (Lepidoptera: Pyralidae) produce ultrasonic advertisement signals attractive to females within several metres. Previous studies showed that females prefer male signals that are louder, delivered at a faster rate, and have a greater asynchrony between pulses produced by the right and left wings. These three signal(More)
A still-air, wing fanning bioassay measured male pheromone response in the pink bollworm moth,Pectinophora gossypiella (Saunders). As pheromone concentration was increased, the duration of wing fanning increased while its latency decreased. Response duration was longest for the natural pheromone blend [44∶:56 (Z,E)- and (Z,Z)-7,11-hexadecadienyl acetates],(More)
This study examines the analysis of arthropod orientation data. Three problems are discussed: (1) dealing with time as it applies to spatial data, (2) determining the appropriate movelength to be used in collecting and in analyzing data, and (3) defining a turn, to discriminate between "gait noise" and course changes. The main objective is to determine the(More)
The alternation of stationary periods and periods of movement may be an important feature of an animal's search tactic. Unambiguously differentiating stops and moves may be difficult, especially from highly resolved digitized pathways, but their identification may be essential for understanding an animal's searching behavior. In this paper, we describe a(More)
Drawing principally on examples and literature from the Anglosphere, the author argues that the high salience given to "trust" and "trustworthiness" in recent scholarly literature, and which (notably in Putnam's work) attributes declining trust to a widely mistrusted mass media does not acknowledge the trustbuilding potential (realised in some instances) of(More)
BACKGROUND AND PURPOSE von Willebrand factor propeptide (VWF:Ag II) is potentially a more sensitive marker of acute endothelial activation than von Willebrand factor antigen (VWF:Ag). These biomarkers have not been simultaneously assessed in asymptomatic versus symptomatic carotid stenosis patients. The relationship between endothelial activation and(More)