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1.
There are numerous reports of invertebrates that are visual mimics of ants, but no formal reports of mimicry of an ant, by
an ant. Two endemic Australian ants, Myrmecia fulvipes and Camponotus bendigensis are remarkably similar in colour and size; both are generally black but have red legs and golden gasters. The density and
hue of the pubescence of each ant's gaster are relatively uncommon in ants, but are very rare when combined with the black
forebody and red legs. The ants are similarly sized but are smaller than other species closely related to M. fulvipes. The range of C. bendigensis lies entirely within that of M. fulvipes, and both species excavate ground nests in open woodland. Finally, workers of both species are crepuscular and forage solitarily.
These data suggest that the relatively benign formicine C. bendigensis is a Batesian mimic of the formidable myrmeciine M. fulvipes.
Received: 9 August 1999 / Accepted in revised form: 22 December 1999 相似文献
2.
Bruce A. Tichenor Leslie A. Sparks James B. White Merrill D. Jackson 《Journal of the Air & Waste Management Association (1995)》2013,63(4):487-492
Evaluation of Indoor air pollution problems requires an understanding of the relationship between sources, air movement, and outdoor air exchange. Research is underway to investigate these relationships. A three-phase program is being implemented: 1) Environmental chambers are used to provide source emission factors for specific indoor pollutants; 2) An IAQ (Indoor Air Quality) model has been developed to calculate indoor pollutant concentrations based on chamber emissions data and the air exchange and air movement within the indoor environment; and 3) An IAQ test house is used to conduct experiments to evaluate the model results. Examples are provided to show how this coordinated approach can be used to evaluate specific sources of indoor air pollution. Two sources are examined: 1) para-dichlorobenzene emissions from solid moth repellant; and 2) particle emissions from unvented kerosene heaters. The evaluation process for both sources followed the three-phase approach discussed above. Para-dichlorobenzene emission factors were determined by small chamber testing at EPA’s Air and Energy Engineering Research Laboratory. Particle emission factors for the kerosene heaters were developed In large chambers at the J. B. Pierce Foundation Laboratory. Both sources were subsequently evaluated in EPA’s IAQ test house. The IAQ model predictions showed good agreement with the test house measurements when appropriate values were provided for source emissions, outside air exchange, in-house air movement, and deposition on “sink” surfaces. 相似文献
3.
Silvicultural guidelines are presented for the management of intermountain Douglas-fir (Pseudotsuga menziesii) stands for sawtimber production and goshawk (Accipiter gentilis) nesting habitat in the northern Rocky Mountains. Data from 14 goshawk nest stands in Douglas-fir forests on the Targhee
National Forest in Idaho (Patla 1991) were used to characterize the range of stand conditions considered suitable for goshawk
nesting. A density management regime is presented using Reineke's stand density index that includes a technical rotation designed
to produce sawlogs with a single commercial thinning. On average timber-growing sites, stands reach goshawk habitat suitability
when site height is 25 m at age 75 and provide 65 years of goshawk nesting habitat until the final harvest at age 140. Approximately
1320 m3/ha are harvested over the rotation. On higher-quality sites, rotation length declines from 140 to 85 years, of which roughly
35 years are suitable for goshawk nesting. 相似文献
4.
Hawthorne L Beyer Evelyn H Merrill Nathan Varley Mark S Boyce 《Ecological applications》2007,17(6):1563-1571
Reintroduction of wolves (Canis lupus) to Yellowstone National Park in 1995-1996 has been argued to promote a trophic cascade by altering elk (Cervus elaphus) density, habitat-selection patterns, and behavior that, in turn, could lead to changes within the plant communities used by elk. We sampled two species of willow (Salix boothii and S. geyeriana) on the northern winter range to determine whether (1) there was quantitative evidence of increased willow growth following wolf reintroduction, (2) browsing by elk affected willow growth, and (3) any increase in growth observed was greater than that expected by climatic and hydrological factors alone, thereby indicating a trophic cascade caused by wolves. Using stem sectioning techniques to quantify historical growth patterns we found an approximately twofold increase in stem growth-ring area following wolf reintroduction for both species of willow. This increase could not be explained by climate and hydrological factors alone; the presence of wolves on the landscape was a significant predictor of stem growth above and beyond these abiotic factors. Growth-ring area was positively correlated with the previous year's ring area and negatively correlated with the percentage of twigs browsed from the stem during the winter preceding growth, indicating that elk browse impeded stem growth. Our results are consistent with the hypothesis of a behaviorally mediated trophic cascade on Yellowstone's northern winter range following wolf reintroduction. We suggest that the community-altering effects of wolf restoration are an endorsement of ecological-process management in Yellowstone National Park. 相似文献
5.
Hannah W. McKenzie Christopher L. Jerde Darcy R. Visscher Evelyn H. Merrill Mark A. Lewis 《Environmental and Ecological Statistics》2009,16(4):531-546
Global Positioning System (GPS) collars are increasingly used to study animal movement and habitat use. Measurement error
is defined as the difference between the observed and true value being measured. In GPS data measurement error is referred
to as location error and leads to misclassification of observed locations into habitat types. This is particularily true when
studying habitats of small spatial extent with large amounts of edge, such as linear features (e.g. roads and seismic lines).
However, no consistent framework exists to address the effect of measurement error on habitat classification of observed locations
and resulting biological inference. We developed a mechanistic, empirically-based method for buffering linear features that
minimizes the underestimation of animal use introduced by GPS measurement error. To do this we quantified the distribution
of measurement error and derived an explicit formula for buffer radius which incorporated the error distribution, the width
of the linear feature, and a predefined amount of acceptable type I error in location classification. In our empirical study
we found the GPS measurement error of the Lotek GPS_3300 collar followed a bivariate Laplace distribution with parameter ρ = 0.1123. When we applied our method to a simulated landscape, type I error was reduced by 57%. This study highlights the
need to address the effect of GPS measurement error in animal location classification, particularily for habitats of small
spatial extent. 相似文献
6.
Conservation Biology and Carnivore Conservation in the Rocky Mountains 总被引:17,自引:0,他引:17
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8.
Amy Merrill Lynne Rosenblum-Vos Deborah A. Driscoll Katherine Daley Karen Treat 《黑龙江环境通报》2005,25(1):20-22
Manifestations of Fanconi Anemia Complementation Group C (FA-C) include multiple major congenital malformations, hypoplastic radius, absent thumb, growth retardation, elfin-like facial features, microphthalmia, microcephaly, café-au-lait spots, early onset of hematologic disease and poor survival (Auerbach, 1997). We describe two cases in which second-trimester sonographic findings led to parental carrier testing for FA-C and subsequent prenatal diagnosis of affected fetuses. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
9.
Legally designated wilderness areas are acknowledged to be an important element in strategies to conserve biological diversity
in United States. However, because of the restrictions on consumptive uses in wilderness, their establishment is normally
contentious. Criteria for establishment have typically been associated with opportunity and aesthetic and experiential values.
Biological data have not normally played a major role in guiding wilderness establishment. We present four wilderness allocation
options for those public lands considered suitable for wilderness designation in Idaho. These options cover the span of choices
presently available to wilderness planners in the state and range from not establishing any new wilderness areas to the inclusion
of all suitable lands in wilderness. All options are evaluated using spatial biological data from the National Biological
Survey's Gap Analysis Project. A conservation strategy that would protect a minimum of 10% of the area occupied by each of
113 native vegetation types and at a minimum 10% of the distribution of each of 368 vertebrate species was evaluated for each
option. Only the inclusion of all suitable lands in wilderness, creating a system of 5.1 million ha came close to achieving
these goals, protecting 65% of the vegetation types and 56% of the vertebrate species. We feel this approach, which allows
planners to evaluate the ecological merits of proposed widerness units along with other values, can provide a means to resolve
the impasse over additional wilderness designation in Idaho. 相似文献
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