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611.
Whale sharks (Rhincodon typus Smith) aggregate seasonally (March–June) to feed in coastal waters off Ningaloo Reef, Western Australia. Pop-up archival
tags were attached to 19 individuals (total lengths 4.5–11.0 m) at this location in early May of 2003 and 2004 to examine
their horizontal and vertical movements. The long-term movement patterns of six whale sharks were documented, all of which
travelled northeast into the Indian Ocean after departing Ningaloo Reef. They used both inshore and offshore habitats and
made extensive vertical movements, occasionally to a depth of at least 980 m. Frequent up-and-down movements, diel vertical
migration, and crepuscular descents were evident in the depth records. The sharks experienced ambient temperatures ranging
between 4.2 and 28.7°C and encountered gradients of up to 20.8°C on dives. 相似文献
612.
External devices on penguins: how important is shape? 总被引:4,自引:0,他引:4
Many researchers use external recording or transmitting devices to elucidate the marine ecology of fish, mammals and birds. Deleterious effects of these instruments on the parameters researchers wish to measure are hardly ever discussed in the literature. Research has shown that, in penguins, volume and cross-sectional area of instruments negatively correlate with swimming speed. dive depth and breeding success, and that device colour affects bird behaviour. Here, a large (200 g, cross-sectional area 2100 mm2) streamlined device was attached to the lower back of Adélie penguins (Pygoscelis adeliae on Ardley Island, South Shetland Island in 1992) and its effects on bird swimming speed and energetics were measured in a water canal in Antarctica. Although the device was 10.5% of penguin cross-sectional area, swimming speed was reduced by only 8.3% and mean power input increased by only 5.6% while swimming. Although our streamlined device was five times more voluminous than one of our older units, the effect on swimming energetics could be reduced by 87%. 相似文献
613.
David Sloan Wilson 《Behavioral ecology and sociobiology》1977,2(4):421-425
Summary The evolution of altruism does not necessarily require an extreme amount of kinship. This point is illustrated with an analysis of altruistic behavior in the Trematode parasite Dicrocoelium dendriticum, which apparently can evolve even when the parasites of the host are derived from as many as five different parents. 相似文献
614.
Abstract: Soberón and Llorente (1993) proposed pure-birth stochastic processes as theoretical models for species-accumulation curves, and these processes have frequently been used to describe the progress of biological inventories. We describe, in algorithmic form, an alternative statistical analysis based on a likelihood approach ( Díaz-Francés & Gorostiza 2002 ) that provides mathematical rigor to the ideas in Soberón and Llorente (1993) and improves the estimation of the models by incorporating the facts that the variance of the error is not constant and that the observations are correlated. Additionally, we used the likelihood ratios between candidate models as an objective procedure for model selection, allowing comparison between the goodness of fit of various models. The software for these statistical methods can now be downloaded off the Internet. We used two examples of butterfly data sets to illustrate the use of the methods and the software. 相似文献
615.
616.
Moukaram Tertuliano Jeffery K. Tomberlin Zeljko Jurjevic David Wilson Glen C. Rains W. J. Lewis 《Chemoecology》2005,15(2):89-95
Summary. The parasitic wasp Microplitis croceipes (Cresson) (Hymenoptera: Braconidae) learns to associate odors with food resources and subsequently exhibits a characteristic food-seeking behavior when encountering the learned odor. Wasps so conditioned, learned and subsequently demonstrated an ability to distinguish among aflatoxigenic and non-aflatoxigenic Aspergillus flavus and A. parasiticus strains. The effects of fungal species, strain, age (5, 10-12, 20, and 30 d) and growth media (potato dextrose agar, peanut agar and corn agar) on the learning and recognition responses of the conditioned wasps were examined. The level of differentiation between fungal strains by conditioned wasps was lowest when working with 5-d-old fungal cultures but increased with age and generally peaked with 20-d-old fungi. Wasps responded generally stronger to the fungal strain conditioned to independent of growth media. This ability of parasitic wasps to learn and distinguish fungal odors can open new avenues in insect learning. 相似文献
617.
618.
Gary D. Lynne J. Walter Milon Michael E. Wilson 《Journal of the American Water Resources Association》1990,26(4):669-676
ABSTRACT: Scarcity combined with differences in values, beliefs, and attitudes can lead to behavior differences and conflicts over water. This paper develops an index for measuring potential conflict using survey information about water attitudes and beliefs of individuals in three groups in a Florida case study. The index helps in assessing the current capability of the institution to reduce conflict. The results suggest that the current institution is effective, but changes may help to streamline the consumptive-use permitting process, to improve educational programs, and to seek improved institutional arrangements to reduce future conflict over economic uses of water. 相似文献
619.
620.