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Behaviors Used (behavior + used)
Selected AbstractsRole of the neuropeptide CCAP in Drosophila cardiac functionDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2005Davide Dulcis Abstract The heartbeat of adult Drosophila melanogaster displays two cardiac phases, the anterograde and retrograde beat, which occur in cyclic alternation. Previous work demonstrated that the abdominal heart becomes segmentally innervated during metamorphosis by peripheral neurons that express crustacean cardioactive peptide (CCAP). CCAP has a cardioacceleratory effect when it is applied in vitro. The role of CCAP in adult cardiac function was studied in intact adult flies using targeted cell ablation and RNA interference (RNAi). Optical detection of heart activity showed that targeted ablation of CCAP neurons selectively altered the anterograde beat, without apparently altering the cyclic cardiac reversal. Normal development of the abdominal heart and of the remainder of cardiac innervation in flies lacking CCAP neurons was confirmed by immunocytochemistry. Thus, in addition to its important role in ecdysis behavior (the behavior used by insects to shed the remains of the old cuticle at the end of the molt), CCAP may control the level of activity of the anterograde cardiac pacemaker in the adult fly. Expression of double stranded CCAP RNA in the CCAP neurons (targeted CCAP RNAi) caused a significant reduction in CCAP expression. However, this reduction was not sufficient to compromise CCAP's function in ecdysis behavior and heartbeat regulation. © 2005 Wiley Periodicals, Inc. J Neurobiol, 2005 [source] Selective Defecation and Selective Foraging: Antiparasite Behavior in Wild Ungulates?ETHOLOGY, Issue 11 2004Vanessa O. Ezenwa Selective defecation and selective foraging are two potential antiparasite behaviors used by grazing ungulates to reduce infection by fecal,oral transmitted parasites. While there is some evidence that domestic species use these strategies, less is known about the occurrence and efficacy of these behaviors in wild ungulates. In this study, I examined whether wild antelope use selective defecation and selective foraging strategies to reduce exposure to gastrointestinal nematode parasites. By quantifying parasite levels in the environment in relation to the defecation patterns of three species, dik-dik (Madoqua kirkii), Grant's gazelle (Gazella granti), and impala (Aepyceros melampus), I found that nematode larval concentrations in pasture were higher in the vicinity of clusters of feces (dung middens) compared to single fecal pellet groups or dung-free areas. In addition, experimental feeding trials in free-ranging dik-dik showed that individuals selectively avoided feeding near concentrations of feces. Given that increased parasite contamination was found in the immediate vicinity of fecal clusters, fecal avoidance could help reduce host consumption of parasites and may therefore be an effective antiparasite behavior for certain species. On the other hand, while the concentration of parasite larvae in the vicinity of middens coupled with host avoidance of these areas during grazing could reduce host contact with parasites, results showing a positive correlation between the number of middens in a habitat and larval abundance at control sites suggest that dung middens might increase and not decrease overall host exposure to parasites. If this is the case, dung midden formation may not be a viable antiparasite strategy. [source] Hyperactivity, startle reactivity and cell-proliferation deficits are resistant to chronic lithium treatment in adult Nr2e1frc/frc miceGENES, BRAIN AND BEHAVIOR, Issue 7 2010B. K. Y. Wong The NR2E1 region on Chromosome 6q21-22 has been repeatedly linked to bipolar disorder (BP) and NR2E1 has been associated with BP, and more specifically bipolar I disorder (BPI). In addition, patient sequencing has shown an enrichment of rare candidate-regulatory variants. Interestingly, mice carrying either spontaneous (Nr2e1frc) or targeted (Tlx,) deletions of Nr2e1 (here collectively known as Nr2e1 -null) show similar neurological and behavioral anomalies, including hypoplasia of the cerebrum, reduced neural stem cell proliferation, extreme aggression and deficits in fear conditioning; these are the traits that have been observed in some patients with BP. Thus, NR2E1 is a positional and functional candidate for a role in BP. However, no Nr2e1 -null mice have been fully evaluated for behaviors used to model BP in rodents or pharmacological responses to drugs effective in treating BP symptoms. In this study we examine Nr2e1frc/frc mice, homozygous for the spontaneous deletion, for abnormalities in activity, learning and information processing, and cell proliferation; these are the phenotypes that are either affected in patients with BP or commonly assessed in rodent models of BP. The effect of lithium, a drug used to treat BP, was also evaluated for its ability to attenuate Nr2e1frc/frc behavioral and neural stem cell-proliferation phenotypes. We show for the first time that Nr2e1 -null mice exhibit extreme hyperactivity in the open field as early as postnatal day 18 and in the home cage, deficits in open-field habituation and passive avoidance, and surprisingly, an absence of acoustic startle. We observed a reduction in neural stem/progenitor cell proliferation in Nr2e1frc/frc mice, similar to that seen in other Nr2e1 -null strains. These behavioral and cell-proliferation phenotypes were resistant to chronic-adult-lithium treatment. Thus, Nr2e1frc/frc mice exhibit behavioral traits used to model BP in rodents, but our results do not support Nr2e1frc/frc mice as pharmacological models for BP. [source] Stair Performance in People Aged 75 and OlderJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 4 2004Kathryn A. Hamel PhD Objectives: To examine specific behaviors used by older adults while ascending and descending stairs and to assess the relationships between confidence and stair performance. Design: Cross-sectional. Setting: Center for Locomotion Studies, The Pennsylvania State University. Participants: Sixteen male (mean age=82.7, range= 77,89) and 16 female (mean age=82.2, range=77,87) community-dwelling adults. Measurements: A stair self-efficacy (SSE) test was created to assess individuals' confidence in their safety on stairs. Observational stair performance measures, measures of walking speed on stairs, and the total SSE score were examined for differences due to sex, and the relationships between SSE and specific stair behaviors were assessed. Results: There was a significant relationship between SSE and the safety precautions taken during stair negotiation. Those with lower SSE were more likely to ascend and descend the stairs at a slower speed, use the handrail to a greater extent, and position themselves closer to the rail. The women had lower domain-specific SSE and tended to use the handrail to a greater extent than men even though there were no sex differences in self-reported functional ability or general falls and mobility confidence. A small group of subjects exhibited characteristics of instability, particularly during stair descent, yet most of this group had high SSE scores and failed to use the handrail. Conclusion: It appears that confidence related to stair negotiation plays a major role in determining risk-taking propensity during stair use in older adults. [source] USE OF SOIL AND WATER PROTECTION PRACTICES AMONG FARMERS IN THE NORTH CENTRAL REGION OF THE UNITED STATES,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2000Ted L. Napier ABSTRACT: Data were collected in the fall of 1998 and the winter of 1999 from 1,011 land owner-operators within three watersheds in the North Central Region of the United States to assess adoption of soil and water protection practices. Farm owner-operators were asked to indicate how frequently they used 18 different agricultural production practices. Many farmers within the three watersheds had adopted conservation protection practices. However, they also employed production practices that could negate many of the environmental benefits associated with conservation practices in use. Comparison of adoption behaviors used in the three watersheds revealed significant differences among the study groups. Respondents in the Iowa and Ohio watersheds reported greater use of conservation production systems than did farmers in Minnesota. However, there were no significant differences between Ohio and Iowa farmers in terms of use of conservation production practices. This was surprising, since farmers in the Ohio watershed had received massive amounts of public and private investments to motivate them to adopt and to continue using conservation production systems. These findings bring into serious question the use of traditional voluntary conservation programs such as those employed in the Ohio watershed. Study findings suggest that new policy approaches should be considered. It is argued that "whole farm planning" should be a significant component of new agricultural conservation policy. [source] The ontogeny of handling hard-to-process food in wild brown capuchins (Cebus apella apella): evidence from foraging on the fruit of Maximiliana maripaAMERICAN JOURNAL OF PRIMATOLOGY, Issue 11 2010Noëlle Gunst Abstract We examined age-related differences in wild brown capuchins' foraging efficiency and the food-processing behaviors directed toward maripa palm fruit (Maximiliana maripa). A detailed comparison of the different foraging techniques showed that plucking the fruit from the infructescence constituted the main difficulty of this task. Foraging efficiency tended to increase with age, with a threshold at which sufficient strength allowed immatures by the age of three to reach adult-level efficiency. Youngsters spent more time than older individuals browsing the infructescence and pulling the fruit in an attempt to harvest it. Infants tried to compensate for their inability to pluck fruit by adopting alternative strategies but with low payback, such as gnawing unplucked fruit and opportunistically scrounging others' partially processed food. Although around 2 years of age, young capuchins exhibited all of the behaviors used by adults, they did not reach adult-level proficiency at feeding on maripa until about 3 years (older juveniles). We compared this developmental pattern with that of extractive foraging on beetle larvae (Myelobia sp.) hidden in bamboo stalks, a more difficult food for these monkeys [Gunst N, Boinski S, Fragaszy DM. Behaviour 145:195,229, 2008]. For maripa, the challenge was mainly physical (plucking the fruit) once a tree was encountered, whereas for larvae, the challenge was primarily perceptual (locating the hidden larvae). For both foods, capuchins practice for years before achieving adult-level foraging competence, and the timeline is extended for larvae foraging (until 6 years) compared with maripa (3 years). The differing combinations of opportunities and challenges for learning to forage on these different foods illustrate how young generalist foragers (i.e. exploiting a large number of animal and plant species) may compensate for their low efficiency in extractive foraging tasks by showing earlier competence in processing less difficult but nutritious foods, such as maripa fruit. Am. J. Primatol. 72:960,973, 2010. © 2010 Wiley-Liss, Inc. [source] Parental Guidance in Preschoolers' Understanding of Spatial-Graphic RepresentationsCHILD DEVELOPMENT, Issue 3 2004Lisa E. Szechter This research was designed to observe whether parents guide their children's understanding of spatial-graphic representations and, if so, to describe the quality of the strategies they use. Parents read a picture book to their preschoolers (3 or 5 years, N=31) and children completed spatial-graphic comprehension tasks. Observational data revealed a range of creative behaviors used to address the book's spatial-graphic challenges. The incidence and quality of parental spatial-graphic behaviors were significantly related to 5-year-old children's performance on spatial-graphic measures. These findings, as well as the paucity of parent attention to aesthetics or graphic production techniques, are discussed in relation to representational development and educational practice. [source] | ||||||||||