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1.
DANIEL J. C. KRONAUER JÜRGEN GADAU JACOBUS J. BOOMSMA 《Molecular ecology resources》2007,7(4):688-690
Here we describe 12 polymorphic microsatellite loci that were cloned and characterized for three species of army ants: the North American Neivamyrmex nigrescens, and the Asian Aenictus laeviceps and Aenictus dentatus. Observed and expected heterozygosities ranged from 0.37 to 0.97 (mean 0.70), and from 0.48 to 0.95 (mean 0.72), respectively. We observed 2–30 (mean 12) alleles per locus. These new genetic markers will be useful for studies of overall population structure and the complex pedigrees in colonies of army ants. 相似文献
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Effects of resource availability and social parasite invasion on field colonies of Bombus terrestris
CLAIRE CARVELL PETER ROTHERY RICHARD F. PYWELL MATTHEW S. HEARD 《Ecological Entomology》2008,33(3):321-327
Abstract. 1. The survival, growth and fecundity of bumblebee colonies are affected by the availability of food resources and presence of natural enemies. Social parasites (cuckoo bumblebees and other bumblebees) can invade colonies and reduce or halt successful reproduction; however, little is known about the frequency of invasion or what environmental factors determine their success in the field.
2. We used 48 experimental colonies of the bumblebee Bombus terrestris , and manipulated both resource availability at the landscape scale and date of colony founding, to explore invasion rates of social parasites and their effect on the performance of host colonies.
3. Proximity to abundant forage resources (fields of flowering oilseed rape) and early colony founding significantly increased the probability of parasite invasion and thus offset the potential positive effects of these factors on bumblebee colony performance.
4. The study concludes that optimal colony location may be among intermediate levels of resources and supports schemes designed to increase the heterogeneity of forage resources for bumblebees across agricultural landscapes. 相似文献
2. We used 48 experimental colonies of the bumblebee Bombus terrestris , and manipulated both resource availability at the landscape scale and date of colony founding, to explore invasion rates of social parasites and their effect on the performance of host colonies.
3. Proximity to abundant forage resources (fields of flowering oilseed rape) and early colony founding significantly increased the probability of parasite invasion and thus offset the potential positive effects of these factors on bumblebee colony performance.
4. The study concludes that optimal colony location may be among intermediate levels of resources and supports schemes designed to increase the heterogeneity of forage resources for bumblebees across agricultural landscapes. 相似文献
4.
Multitargeting involves the application of molecules that are deliberately intended to bind to two or more unrelated cellular targets with high affinity. In epigenetic chemical biology and drug discovery, the rational design of multitargeting agents has evolved to a sophisticated level, and there are now five examples that have reached clinical trials. This review covers recent developments in the field and future prospects. 相似文献
5.
Sonja T. Chou 《中国实验动物学杂志》2011,(1):5-11
2009年11月份在西安举行由中国实验动物学会发起的实验动物医药技术培训研讨会上,本人做了关于实验小鼠种群管理的演讲。其主题涵盖了小鼠繁殖性能的维护和基因工程种群的管理。本篇文章的目的在于强调其所涵盖的材料并为进一步研究提供参考。如若对本文所讨论的内容希望有更深刻的理解,这篇文章所引用的参考资料值得进一步的阅读。另外本文未涉及远交系小鼠的繁殖培育和基因管理,但如有需要可以联系本文作者,可推荐需阅读的材料清单。 相似文献
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Resource availability or distribution may affect interindividual competition in species such as primates, which forage in social groups, and several field studies suggest that dominance status predicts access to restricted food sources. Increased competition due to restricted resources may result in the intensification of aggressive behaviors. The study reported here examines the impact of manipulation of the distribution of food resources in a laboratory-housed group of bonnet macaques to assess the impact of distribution on aggressive behaviors. Food was restricted to a space which allowed access to only one or two individuals at a time or was dispersed throughout the living enclosure to allow universal access in alternating periods. During periods of clumped distribution, the monkeys obtained access to the food in order of their dominance status in the group. In addition, overall levels of aggressive behaviors increased, submissive behavior increased, and play decreased during periods of clumped distribution of food. These results confirm the findings from field studies indicating increases in agonism with restriction of food resources. These findings also have implications for primate colony management, in terms of developing strategies for minimizing intragroup aggression in captive groups. 相似文献
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Mar García 《FEMS microbiology letters》1995,131(1):107-111
Abstract Colonies of Streptomyces antibioticus were studied by transmission and scanning electron microscopy. The micrographs show that substrate mycelium growth takes place among an intercellular material and this mycelium is covered by a surface film. This structure could be a boundary between the aerial mycelium and the substrate mycelium. 相似文献
9.
We developed primers for five polymorphic microsatellite loci to analyse the genetic structure of colonies in an invading Argentine ant population located in Haleakala National Park on the island of Maui, Hawaii. Microsatellite loci were isolated using both a polymerase chain reaction‐based and a cloning‐based method. With a range of 3–18 alleles and expected levels of heterozygosity of 0.46–0.77, these loci provide useful markers for the detection of colony and population structure in new or expanding populations of this species. 相似文献
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