Laboratory and Field Evaluation of Host-Related Foraging Odor-Cue Combinations to Attract Drosophila suzukii (Diptera: Drosophilidae).

The invasive spotted-wing drosophila, Drosophila suzukii (Matsumura), is a major pest of soft-skinned fruits. Since its introduction into North America and Europe, significant progress has been made in understanding the volatile cues used by this fly during food, oviposition site, and mate finding. Despite this progress, commercially available lures are non-selective. Here, we tested two Hanseniaspora uvarum (Niehaus) yeast compounds (isoamyl acetate and isobutyl acetate) and a leaf compound ß-cyclocitral alone and in combination with a blend of four fermentation compounds ('Fermentation lure': acetic acid, ethanol, methionol, and acetoin) to improve D. suzukii attraction and selectivity. In laboratory assays, males and females were attracted to all seven individual compounds, although in electrophysiological assays, their antennae exhibited a dose-dependent response to only four of these compounds. In two-choice cage studies, the Fermentation lure was more attractive to D. suzukii than water controls, whereas ß-cyclocitral and the mixture of isoamyl acetate and isobutyl acetate were not attractive in this larger-cage study. Moreover, adding the two-component H. uvarum compound blend to the Fermentation lure reduced D. suzukii attraction to the Fermentation blend. When these experiments were repeated in blueberry, raspberry, blackberry, and cherry orchards across several states in the United States over 2 yr, similar outcomes were observed: ß-cyclocitral or the mixture of the H. uvarum blend did not improve the attractiveness of the Fermentation lure or its selectivity. This study demonstrates that cues from different sources may interfere with each other and reduce D. suzukii attraction to otherwise attractive odor combinations.

Disease-avoidance processes and stigmatization: cues of substandard health arouse heightened discomfort with physical contact.

An evolutionary approach to stigmatization suggests that disease-avoidance processes contribute to some instances of social exclusion. Disease-avoidance processes are over-inclusive, targeting even non-threatening individuals who display cues of substandard health. We investigated whether such cues motivate avoidance of physical contact in particular. In Studies 1 and 2, targets with disease (e.g., leprosy) or atypical morphologies (e.g., amputated leg, obesity) were found to arouse differentially heightened discomfort with physical (versus nonphysical) contact, whereas a criminal target (stigmatized for disease-irrelevant reasons) was found to arouse elevated discomfort for both types of contact. Study 3 used a between-subjects design that eliminated the influence of extraneous factors. A diseased target was found to arouse differentially heightened discomfort with physical (versus nonphysical) contact, and to do so more strongly than any other type of target.

Young children follow pointing over words in interpreting acts of reference.

Adults refer young children's attention to things in two basic ways: through the use of pointing (and other deictic gestures) and words (and other linguistic conventions). In the current studies, we referred young children (2- and 4-year-olds) to things in conflicting ways, that is, by pointing to one object while indicating linguistically (in some way) a different object. In Study 1, a novel word was put into competition with a pointing gesture in a mutual exclusivity paradigm; that is, with a known and a novel object in front of the child, the adult pointed to the known object (e.g. a cup) while simultaneously requesting 'the modi'. In contrast to the findings of Jaswal and Hansen (2006), children followed almost exclusively the pointing gesture. In Study 2, when a known word was put into competition with a pointing gesture - the adult pointed to the novel object but requested 'the car'- children still followed the pointing gesture. In Study 3, the referent of the pointing gesture was doubly contradicted by the lexical information - the adult pointed to a known object (e.g. a cup) but requested 'the car'- in which case children considered pointing and lexical information equally strong. Together, these findings suggest that in disambiguating acts of reference, young children at both 2 and 4 years of age rely most heavily on pragmatic information (e.g. in a pointing gesture), and only secondarily on lexical conventions and principles.

Chemo-orientation using conspecific chemical cues in the stripe-necked terrapin (Mauremys leprosa).

Although chemical communication has been studied intensively in may reptilian species, little attention has been paid to the role that chemical signals play in aquatic reptiles, such as freshwater turtles. Here, I tested the hypothesis that the stripe-necked terrapin (Mauremys leprosa), an abundant freshwater turtle that inhabits the Iberian peninsula, is able to recognize chemical cues from conspecifics in the water and to modify its behavior in response to such cues. I compared the time spent by adult males and adult females in clean water to the time spent in water that presumably contained their own odor, odor from other males, and odor from other females, both during and outside the mating season. Results show that outside the mating season, both males and females avoid water that contains chemical cues from conspecifics of the opposite sex. During the mating season, male turtles clearly select water with chemical cues from females. Moreover, males prefer to occupy water from their home containers over clean water, and avoid water with chemical cues from other conspecific males. Conversely, during the mating season, females prefer to occupy water with chemical cues from other females, but do not select water from their home containers or water from males. The evolution of chemical communication in turtles, its relation to sexual selection processes, and the implications for turtle behavior are discussed.

Orthographic analogies and phonological priming: a comment on Bowey, Vaughan, and Hansen (1998)

J. A. Bowey, L. Vaughan, and J. Hansen (1998, Journal of Experimental Child Psychology, 68, 108-133) carried out two experiments on 6- and 7-year-old children's use of orthographic analogies in word reading. They reported that, following apparently stringent controls for phonological priming effects, beginning analogies (beak-bean) were more frequent in this age group than rime (beak-peak) analogies. From this, they concluded that beginning readers do not reliably use orthographic rimes in reading, even in the clue word task (p. 129). However, the clue word task was not used in this study. This comment highlights two problems with Bowey et al.'s paper. The first is a theoretical one, and the second is methodological. Firstly, Bowey et al. base their investigation on a misunderstanding of U. Goswami and P. E. Bryant's (1990, Phonological skills and learning to read, Hillsdale, NJ: Erlbaum) claims about the role of rhyme and analogy in beginning reading. Secondly, methodological weaknesses, in particular unintended intralist priming effects, seriously limit the conclusions that can be drawn from Bowey et al.'s booklet analogy task.

The limitations of orthographic rime analogies in beginners' word reading: a reply to Goswami (1999)

U. Goswami (1999, Journal of Experimental Child Psychology, 72, 210-219) argues that the findings of J. A. Bowey, L. Vaughan, and J. Hansen (1998, Journal of Experimental Child Psychology, 68, 108-133) are uninterpretable. This paper examines each of Goswami's criticisms of the methodology employed by Bowey et al. (1998). None can explain the differential analogy and phonological priming effects reported by Bowey et al. More fundamentally, none can explain the critical finding of Bowey et al. that, when phonological priming effects are controlled, the size of the end analogy effect is no greater than that of beginning and medial vowel analogy effects. Furthermore, some of Goswami's criticisms cast considerable doubt on the generalizability of findings from her version of the clue word task.

The role of spatial cues in the probe-type serial memory task.

2 experiments were carried out with the aim of clarifying the role of spatial cues in the probe-type serial memory task devised by Atkinson, Hansen, and Bernbach. In experiment 1, preventing the formation of specific items-location associations drastically reduced performance at the early to intermediate serial positions for a group of second graders; yet these children still exhibited a primancy effect (position 1 greater than position2). In experiment 2, the stimulus items were spaced farther apart than usual in an attempt to reduce the contextual uniqueness of the first (far left) item. Children aged 4 and 5 years who were administered this task produced a serial-position function that was essentially flat. It was concluded that (a) spatial cues serve as functional stimuli in the standard probe-type task, and (b) the contextual uniqueness of the first item is probably responsible for the occurrence of primacy in young children. Implications of this research for interpreting age-related differences in the shape of the serial-position curve were also discussed.