Factors Affecting Parental Investment Strategies in Male Waterbugs

Male giant waterbugs (Belostoma flumineum Say) brood eggs oviposited on their dorsi by conspecific females. Preliminary observations indicate that viable egg pads are sometimes discarded before hatching. Theory predicts that such behavior should occur only if costs incurred by brooding exceed benefits of hatching the egg pad. The amount of paternal investment per pad should be similar for both large and small pad sizes, but as egg pads become smaller, investment per egg increases. Thus, smaller pads should be more likely to be discarded unhatched than larger ones. Similarly, egg pads containing inviable eggs should also be more frequently discarded than viable egg pads of the same size. Egg pads should be less frequently discarded as the time invested increases. Effects of these factors (egg pad size, time invested, and egg viability) upon the continuation of paternal care in the giant waterbug were investigated. Results of laboratory experiments suggest that smaller egg pads are less likely to hatch than larger ones, and males appear to be less likely to discard egg pads as temporal investment increases. However, inviability of eggs did not appear to affect the probability of an egg pad being discarded

Do Predator Cues Influence Turn Alternation Behavior in Terrestrial Isopods Porcellio laevis Latreille and Armadillidium vulgare Latreille?

Terrestrial isopods (Crustacea: Oniscidea) make more alternating maze turns in response to negative stimuli, a navigational behavior that corrects divergence from a straight line. The present study investigates this behavioral pattern in two species, Porcellio laevis Latreille and Armadillidium vulgare Latreille, in response to short-term vs. long-term exposure to indirect cues from predatory ants. Neither isopod species increased the number of alternating turns in response to short-term indirect exposure to ants, but both species made significantly more alternating turns following continuous indirect exposure to ants for a period of one-week. These results are surprising given differences in behavioral and morphological predator defenses (the Armadillidiidae curl into defensive postures when attacked, whereas the Porcellionidae flee). The marked similarity in alternating turn behavior of the two families suggests evolutionary conservation of antipredator navigation mechanisms

Do Female Western Mosquitofish, Gambusia affinis, Prefer Ornaments That Males Lack?

Some species in the family Poeciliidae are known for extravagant male ornaments and courtship behavior (e.g. guppies), but the majority of poeciliids are characterized by coercive male copulation attempts that seem to circumvent female choice. In some lineages with male ornaments, female sensory bias may have preceded the evolution of corresponding male signals. We examined female preferences for colorful ornaments in Western mosquitofish, Gambusia affinis, in which males lack ornamentation and reproduce primarily through coercive mating attempts. We found that females exhibited a positional affinity for males that were artificially ornamented with blue coloration over males that had been treated with a transparent ornament. Females exhibited the opposite effect for males treated with red ornaments. In contrast, focal females did not exhibit behavioral discrimination between stimulus females or models (silver fishing lures) with blue versus transparent ornaments. This suggests a sexual context for female discrimination between males of different color. Because tribe Gambusiini is the basal branch of family Poeciliidae, the results of this study are consistent with the hypothesis that female responsiveness to male coloration is the ancestral poeciliid character state. Male ornamentation may have subsequently evolved (or been lost) in different poeciliid lineages

Postoperative Nausea and Vomiting Risk Assessment Tool for Proactive Intervention

https://digitalcommons.psjhealth.org/stvincent-bootcamp/1029/thumbnail.jp

Chapter 19 Noise pollution and its impact on human health and the environment

This chapter deals with (1) the basic theory of sound propagation; (2) an overview of noise pollution problem in view of policy and standards by the World Health Organization, the United States, and the European Union; (3) noise exposure sources from aircraft, road traffic and railways, in-vehicle, work, and construction sites, and occupations, and households; (4) the noise pollution impact on human health and the biological environment; (5) modeling of regional noise-affected habitats in protected and unprotected land areas and the marine environment; (6) noise control measures and sustainability in view of sustainable building design, noise mapping, and control measures such as barriers and berms along roadsides, acoustic building materials, roadway vehicle noise source control, road surface, and pavement materials; and (7) environmental noise pollution management measures and their impact on human health

Factors Affecting Parental Investment Strategies in Male Waterbugs

Male giant waterbugs (Belostoma flumineum Say) brood eggs oviposited on their dorsi by conspecific females. Preliminary observations indicate that viable egg pads are sometimes discarded before hatching. Theory predicts that such behavior should occur only if costs incurred by brooding exceed benefits of hatching the egg pad. The amount of paternal investment per pad should be similar for both large and small pad sizes, but as egg pads become smaller, investment per egg increases. Thus, smaller pads should be more likely to be discarded unhatched than larger ones. Similarly, egg pads containing inviable eggs should also be more frequently discarded than viable egg pads of the same size. Egg pads should be less frequently discarded as the time invested increases. Effects of these factors (egg pad size, time invested, and egg viability) upon the continuation of paternal care in the giant waterbug were investigated. Results of laboratory experiments suggest that smaller egg pads are less likely to hatch than larger ones, and males appear to be less likely to discard egg pads as temporal investment increases. However, inviability of eggs did not appear to affect the probability of an egg pad being discarded

Do Predator Cues Influence Turn Alternation Behavior in Terrestrial Isopods Porcellio laevis Latreille and Armadillidium vulgare Latreille?

Terrestrial isopods (Crustacea: Oniscidea) make more alternating maze turns in response to negative stimuli, a navigational behavior that corrects divergence from a straight line. The present study investigates this behavioral pattern in two species, Porcellio laevis Latreille and Armadillidium vulgare Latreille, in response to short-term vs. long-term exposure to indirect cues from predatory ants. Neither isopod species increased the number of alternating turns in response to short-term indirect exposure to ants, but both species made significantly more alternating turns following continuous indirect exposure to ants for a period of one-week. These results are surprising given differences in behavioral and morphological predator defenses (the Armadillidiidae curl into defensive postures when attacked, whereas the Porcellionidae flee). The marked similarity in alternating turn behavior of the two families suggests evolutionary conservation of antipredator navigation mechanisms