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391.
Female-Female Competition in Bornean Orangutans 总被引:1,自引:1,他引:0
Cheryl Knott Lydia Beaudrot Tamaini Snaith Sarah White Hartmut Tschauner George Planansky 《International journal of primatology》2008,29(4):975-997
The mostly solitary ranging of orangutans and the large areas over which they traverse have hampered quantification of Bornean
orangutan ranging patterns and feeding competition. Because of their semisolitary existence, female orangutans have few competitive
interactions among themselves. However, contest and scramble types of competition occur, and researchers consider both to
be important for the species. Using 9 yr of data and >22,300 h of observation of adult female orangutans in Gunung Palung
National Park in Indonesian Borneo, we examined both forms of competition. Based on our analyses, we have 4 conclusions: 1)
Adult female orangutans have highly overlapping home ranges, and thus there is potential for scramble competition to impose
a cost. 2) Adult female orangutans actively avoid each other, suggesting that scramble competition indeed imposes a cost.
3) Adult females have distinct core areas that overlap to a lesser degree than home ranges do. 4) Analyses of contest competition
reveal a slight spatial component to female competition for the first time. Preliminary evidence for core area defense and
passive range exclusion may be among the mechanisms responsible for maintaining distinct adult female core areas. 相似文献
392.
393.
Stomach residence time was tested over 24 h in three size classes of Oreochromis mossambicus using juvenile Lates calcarifer. In all 63 observations, the fish prey was digested within 24 h of consumption and most probably within 1 h, suggesting a need to re‐evaluate the trophic status and potential effects of this highly invasive species. 相似文献
394.
Victoria Woshner Katrina Knott Randall Wells Carla Willetto Rhonda Swor Todd O’Hara 《EcoHealth》2008,5(3):360-370
Blood and epidermal biopsies from free-ranging Tursiops truncatus captured and released during either summer or winter health assessments in Sarasota Bay, FL, were evaluated for concentrations
of mercury, selenium, stable isotopes (δ13C and δ15N), and blood glutathione peroxidase activity in conjunction with routine hematology and serum chemistry panels. Major objectives
were to: 1) quantify and describe relationships among mercury, selenium, glutathione peroxidase, and stable isotopes of C
and N in blood and epidermis; 2) elucidate major parameters that influence blood mercury and glutathione peroxidase activity;
3) relate measures of tissue mercury, selenium, and glutathione peroxidase to specific ecological, hematological, morphological,
or life history parameters, including season, sex, age, and trophic level. Mercury in both tissues examined is almost exclusively
methylmercury. Epidermal concentrations of mercury and selenium reflect their respective amounts in blood, albeit at several
times blood concentrations of mercury. The strong association between blood mercury and serum selenium, in conjunction with
a lack of significant correlation between blood mercury and glutathione peroxidase, implies that a substantial proportion
of blood mercury is affiliated with another selenium-containing moiety or is related to recent dietary intakes (e.g., trophic
level, intensive fish consumption). Circulating blood mercury may be described in terms of serum selenium concentration, along
with interaction terms among serum selenium, blood δ15N, and age. Current selenium concentrations in Sarasota Bay dolphins appear adequate for maintenance of blood glutathione
peroxidase activity. However, dolphins evidently are subject to seasonal exacerbation of oxidative stress, which might render
them more vulnerable to toxic effects of mercury.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
395.
ABSTRACT: BACKGROUND: To ascertain the understanding of 2009 pandemic (H1N1) influenza and relevant infection control measures in an emergency department population and to assess the effectiveness of education campaigns in informing the public about the pandemic. METHODS: Questionnaires were administered to patients, visitors, non-clinical staff and volunteers. Data were collected on knowledge, preventative measures, information sources, attitudes to government and media reporting, perceived seriousness, behaviour change and intended compliance with future measures. Results were used to construct an overall knowledge score. RESULTS: There were 252 participants. Traditional forms of mass media (138 [55%]) remained the principal information source. Approximately 70% (176) accurately described mode of transmission and recommended precautions and 68% (175) reported behaviour change because of the pandemic. Gaps in knowledge included failure to identify certain high risk groups. Recall of government campaigns was significantly associated with a higher knowledge score. 60% (151) thought that authorities and media had exaggerated the threat; only 40% (101) would comply with recommended measures in a future pandemic. CONCLUSIONS: The knowledge regarding pandemic influenza was high in this population and positively affected by official campaigns. Pandemic planning should address knowledge gaps and the impression that authorities had exaggerated the public-health threat. 相似文献
396.
Anna-Lotta Hiillos Irin Rony Sonja Rueckert K. Emily Knott 《The Journal of eukaryotic microbiology》2023,70(1):e12932
Coinfections of two or more parasites within one host are more of a rule than an exception in nature. Interactions between coinfecting parasites can greatly affect their abundance and prevalence. Characteristics of the host, such as genetic diversity, can also affect the infection dynamics of coinfecting parasites. Here, we investigate for the first time the association of coinfection patterns of two marine apicomplexans, Rhytidocystis sp. and Selenidium pygospionis, with the genetic diversity of their host, the polychaete Pygospio elegans, from natural populations. Host genetic diversity was determined with seven microsatellite loci and summarized as allelic richness, inbreeding coefficient, and individual heterozygosity. We detected nonsignificant correlations between infection loads and both individual host heterozygosity and population genetic diversity. Prevalence and infection load of Rhytidocystis sp. were higher than those of S. pygospionis, and both varied spatially. Coinfections were common, and almost all hosts infected by S. pygospionis were also infected by Rhytidocystis sp. Rhytidocystis sp. infection load was significantly higher in dual infections. Our results suggest that factors other than host genetic diversity might be more important in marine apicomplexan infection patterns and experimental approaches would be needed to further determine how interactions between the apicomplexans and their host influence infection. 相似文献
397.
398.
5-Aminolevulinic acid (ALA), a precursor of porphyrin synthesis, increased the production of various porphyrin compounds in Candida guilliermondii cells. Metalloporphyrins and protoporphyrin IX (PPIX) were predominantly accumulated, respectively, at ALA concentrations of 0.2-0.4 mM and at those higher than 1.5 mM. 2,2;-Dipyridyl which complexed with bivalent metals significantly increased the content of endogenous PPIX even at ALA concentrations lower than 0.5 mM. Under these conditions, the yeast sensitivity to photodynamic effect of visible light (400-600 nm) dramatically increased due to photosensitization by endogenous PPIX. 相似文献
399.
Nathan Charles Bass Joanna Day Tristan L. Guttridge Johann Mourier Nathan A. Knott Catarina Vila Pouca Culum Brown 《Journal of fish biology》2021,99(4):1455-1466
Examining the movement ecology of mesopredators is fundamental to developing an understanding of their biology, ecology and behaviour, as well as the communities and ecosystems they influence. The limited research on the residency and movements of benthic marine mesopredators has primarily used visual tags, which do not allow for the efficient and accurate monitoring of individual space use. In this study, the authors investigated the residency and movement patterns of Port Jackson sharks Heterodontus portusjacksoni (Meyer 1793) at a breeding aggregation site in Jervis Bay, south-eastern Australia, using passive acoustic telemetry to further our understanding of the movement ecology of these important mesopredators. Between 2012 and 2014, individuals were tagged with acoustic transmitters, and their residency and movements within the bay were monitored for up to 4 years. H. portusjacksoni showed strong preferences for particular reefs within and between breeding seasons. Males had significantly higher residency indices at their favoured sites relative to females, suggesting that males may be engaging in territorial behaviour. Conversely, female H. portusjacksoni exhibited higher roaming indices relative to males indicating that females may move between sites to assess males. Finally, H. portusjacksoni showed temporal variation in movements between reefs with individuals typically visiting more reefs at night relative to the day, dusk and dawn corresponding with their nocturnal habits. 相似文献
400.
Abbey E. Wilson Darrell L. Sparks Katrina K. Knott Scott Willard Ashli Brown 《Zoo biology》2020,39(3):176-185
Chemicals present in urine are thought to play an important role in mate identification in the solitary giant panda (Ailuropoda melanoleuca). During the breeding season, females will deposit chemical signals to advertise sexual receptivity to potential mates. The goal of this study was to determine if specific volatile compounds found in female urine could be considered as pheromones that elicit behavioral and physiological responses in males. Experimental simultaneous choice trials were conducted with captive male giant pandas (n = 3) housed at Memphis Zoo, San Diego Zoo, and Zoo Atlanta. Octanoic acid, 1H-pyrrole-2-carboxaldehyde, decanoic acid, and civetone were selected as stimuli because previous studies reported their elevation in urine during the breeding season. Male interest was determined by a behavioral preference toward these volatile compounds diluted in synthetic urine compared with nontreated synthetic urine. Male urine samples were collected 1 week prior, during, and 1 week after the experimental period to assess changes in urinary semiochemical composition and urinary androgen concentrations. No significant differences in investigation response (p = .395) or flehmen response (p = .600) were found when stimuli were compared; however, decanoic acid and civetone elicited a behavioral preference over the control (response ratio > 0.5). The relative abundance of 16 compounds identified in male urine was significantly elevated (p < .05) above baseline values after the males were exposed to the stimuli. Androgen levels were significantly elevated (p < .05) in one male after exposure to 1H-pyrrole-2-carboxaldehyde, decanoic acid, and civetone. These data suggested that civetone and decanoic acid in female urine may motivate sexual responses in males. 相似文献