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71.
Rebecca Leonardi Hannah M. Buchanan‐Smith Valérie Dufour Charlotte MacDonald Andrew Whiten 《American journal of primatology》2010,72(1):33-47
There are potential advantages of housing primates in mixed species exhibits for both the visiting public and the primates themselves. If the primates naturally associate in the wild, it may be more educational and enjoyable for the public to view. Increases in social complexity and stimulation may be enriching for the primates. However, mixed species exhibits might also create welfare problems such as stress from interspecific aggression. We present data on the behavior of single and mixed species groups of capuchin monkeys (Cebus apella) and squirrel monkeys (Saimiri sciureus) housed at the Living Links to Human Evolution Research Centre in the Royal Zoological Society of Scotland's Edinburgh Zoo. These species associate in the wild, gaining foraging benefits and decreased predation. But Cebus are also predators themselves with potential risks for the smaller Saimiri. To study their living together we took scan samples at ≥15 min intervals on single (n=109) and mixed species groups (n=152), and all occurrences of intraspecific aggression and interspecific interactions were recorded. We found no evidence of chronic stress and Saimiri actively chose to associate with Cebus. On 79% of scans, the two species simultaneously occupied the same part of their enclosure. No vertical displacement was observed. Interspecific interactions were common (>2.5/hr), and equally divided among mildly aggressive, neutral, and affiliative interactions such as play. Only one aggressive interaction involved physical contact and was non‐injurious. Aggressive interactions were mostly (65%) displacements and vocal exchanges, initiated almost equally by Cebus and Saimiri. Modifications to the enclosure were successful in reducing these mildly aggressive interactions with affiliative interactions increasing in frequency and diversity. Our data suggest that in carefully designed, large enclosures, naturally associating monkeys are able to live harmoniously and are enriched by each other. Am. J. Primatol. 72:33–47, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
72.
Lindsey E. Rustad 《Plant Ecology》2006,182(1-2):43-62
Evidence continues to accumulate that humans are significantly increasing atmospheric CO2 concentrations, resulting in unprecedented changes in the global climate system. Experimental manipulations of terrestrial
ecosystems and their components have greatly increased our understanding of short-term responses to these global perturbations
and have provided valuable input to ecosystem, dynamic vegetation, and global scale models. However, concerns exist that these
initial experimental responses may be transitory, thereby limiting our ability to extrapolate short-term experimental responses
to infer longer-term effects. To do these extrapolations, it will be necessary to understand changes in response patterns
over time, including alterations in the magnitude, direction, and rate of change of the responses. These issues represent
one of our largest challenges in accurately predicting longer-term changes in ecosystems and associated feedbacks to the climate
system. Key issues that need to be considered when designing future experiments or refining models include: linear vs. non-linear
responses, direct vs. indirect effects, lags in response, acclimation, resource limitation, homeostasis, buffers, thresholds,
ecosystem stoichiometry, turnover rates and times, and alterations in species composition. Although experimental and landscape
evidence for these response patterns exist, extrapolating longer-term response patterns from short-term experiments will ultimately
require a unified multidisciplinary approach, including better communication and collaboration between theoreticists, experimentalists
and modelers. 相似文献
73.
74.
Microsatellites are continuing to increase in popularity for genetic studies. A major drawback, however, is they often need to be isolated de novo. The traditional method (shotgun cloning) generally results in thousands of recombinant clones, which are then screened by Southern hybridization. Results are typically around 2% positive for mammals, but less than 0.4% for birds. Shotgun cloning is therefore generally not an effective method for isolating microsatellites from avian genomes. Several alternative methods have been developed, but the decision as to which method to use is often arbitrary. Here we present results for two microsatellite isolation techniques from four avian species. 相似文献
75.
Ten microsatellite loci were developed for the black‐lipped pearl oyster Pinctada margaritifera with a magnetic bead enrichment protocol. These tetra‐ and dinucleotide markers were polymorphic, with 10 to 43 alleles observed in 97 individuals from two Tuamotu atoll populations. Most loci revealed significant genic differentiation between the two populations and also exhibited some degree of heterozygote deficiencies, probably due to the presence of null alleles. These loci should be very useful to describe genetic structure, genetic variability and reproductive success in the various aquaculture and wild populations of pearl oyster in French Polynesia. 相似文献
76.
ANNA C. D. R. BARBOSA THAÍS C. CORRÊA FELIPE GALZERANI PEDRO M. GALETTI TERUMI HATANAKA 《Molecular ecology resources》2006,6(3):936-938
Prochilodus species inhabit the main river systems of South America and usually present commercial value to inland fishing. In the present study, we describe the isolation and characterization of 13 novel microsatellite loci in Prochilodus argenteus. The number of alleles per polymorphic locus varied from four to 22 and the observed heterozygosity ranged from 0.333 to 0.893. Additionally, cross‐species amplification was successful in two other Prochilodus species. These loci will be useful for studies of the population genetic structure in this fish group. 相似文献
77.
C. SMITH‐KEUNE D. R. JERRY B. S. EVANS M. I. MCCORMICK P. L. MUNDAY G. P. JONES 《Molecular ecology resources》2006,6(4):1036-1038
Eight di‐, tri‐ and tetranucleotide microsatellite markers were developed for the haremic sandperch Parapercis cylindrica using a linker‐ligated, magnetic bead enrichment protocol. Screening of at least 17 individuals showed these markers to be polymorphic with observed heterozygosity ranging from 0.381 to 1.000 (mean = 0.742) and the numbers of alleles ranging from three to 18. The average polymorphic information content for these eight loci was 0.723. These markers may be used for parentage studies aimed at exploring the complex mating strategies employed by this haremic coral reef fish and will be valuable for population genetic studies. 相似文献
78.
A. A. GHEYAS M. CAIRNEY A. E. GILMOUR M. A. SATTAR T. K. DAS B. J. McANDREW D. J. PENMAN J. B. TAGGART 《Molecular ecology resources》2006,6(3):656-659
Captive populations of silver carp (Hypophthalmichthys molitrix), a major aquaculture species in Asia, would undoubtedly benefit from genetic monitoring and improvement programs. We report the isolation and preliminary characterization of 16 microsatellite loci derived from both conventional and microsatellite‐enriched libraries. Inheritance studies confirmed the allelic nature of observed polymorphisms at all loci, while identifying null alleles at two loci. These loci, having varying degrees of polymorphism, should provide useful markers for applied genetic studies. A high degree of cross‐amplification among 10 other cyprinid species suggests that these loci may have more widespread utility. 相似文献
79.
JONATHAN A. NEWMAN 《Global Change Biology》2006,12(9):1634-1642
Climate change will alter the abundance and distribution of species. Predicting these shifts is a challenge for ecologists and essential information for the formation of public policy. Here, I use a mechanistic mathematical model of the interaction between grass growth physiology and aphid population dynamics, coupled with the climate change projections from the UK's Hadley Centre HadCM3 global circulation model (GCM) and Canada's Center for Climate Modeling and Analysis CGCM2 GCM to predict the changes in the abundance and distribution of summer cereal aphid populations in wheat-growing regions of Canada. When used with the HadCM3 projections, the model predicts a latitudinal shift northward in abundances but there is longitudinal variation as well. However, when used with the CGCM2 projections the model predicts that continental regions will see a decline while coastal regions will see an increase in summer cereal aphid populations. These effects are stronger under the higher emissions scenarios. 相似文献
80.
This study assessed the effect of nutrient enrichment on rates of decomposition, ergosterol concentrations (as a measure of
fungal biomass), and rates of fungal sporulation of sweet chestnut (Castanea sativa Miller) leaves in a 3rd order stream (Central Portugal), with medium to high background values of nutrients. Coarse and fine
mesh leaf bags were attached to nutrient diffusing substrata containing NaNO3, KH2PO4, both nutrients, or no additions. Leaf breakdown rates were similar in the four treatments and in the two mesh sizes (k=−0.0155 to −0.0219 day−1). Phosphorus content of P or N + P enriched leaves was higher than in the other treatments after 28 days, but there were
no differences in N concentrations. Ergosterol concentrations associated with decomposing leaves were similar among treatments.
The peak sporulation rates of aquatic hyphomycetes were stimulated by the addition of N + P and N but not by P alone. Results
from the experiment provide evidence that leaf breakdown in the study stream, as a model for streams with naturally medium
to high level of nutrients, was not nutrient-limited, and that fungal reproductive activity was limited by dissolved N but
not by dissolved P in stream water. 相似文献