Abstract:
:Much discussion has occurred in recent years on whether observed patterns of structure in island bird communities are the result of competitive interactions among species or independent rates of colonization and extinction. Here two patterns of structure are presented for birds on 12 West Indian islands. Each of four major foraging guilds shows a distinct species-area pattern on the islands and saturation of species within habitats on larger islands. Frugivores have the steepest species-area curve and highest species numbers at saturation while nectarivores are lowest in both values. Coexisting guild members in saturated habitats are generally of different sizes, with weight differences by a factor of 2 common. On smaller islands, small guild members are absent and size differences among coexisting guild members may increase. In many cases, birds have apparently shifted size to conform to the structural patterns. The consistency of the patterns and variation within component species is highly compatible to explanations invoking competition and complements previously described population and community characteristics of West Indian birds.
journal_name
Proc Natl Acad Sci U S Aauthors
Faaborg Jdoi
10.1073/pnas.79.5.1563keywords:
subject
Has Abstractpub_date
1982-03-01 00:00:00pages
1563-7issue
5eissn
0027-8424issn
1091-6490journal_volume
79pub_type
杂志文章abstract::We have studied a naturally occurring small-molecule antimitotic called diazonamide A. Diazonamide A is highly effective at blocking spindle assembly in mammalian cell culture and does so through a unique mechanism. A biotinylated form of diazonamide A affinity purifies ornithine delta-amino transferase (OAT), a mitoc...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0610832104
更新日期:2007-02-13 00:00:00
abstract::Cyclonic atmospheric vortices of varying intensity, collectively known as low-pressure systems (LPS), travel northwest across central India and produce more than half of the precipitation received by that fertile region and its ∼600 million inhabitants. Yet, future changes in LPS activity are poorly understood, due in...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1709031115
更新日期:2018-03-13 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.92.10.4547
更新日期:1995-05-09 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.87.19.7457
更新日期:1990-10-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.85.3.679
更新日期:1988-02-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.86.17.6469
更新日期:1989-09-01 00:00:00
abstract::Opitz syndrome (OS) is a genetically heterogeneous disorder characterized by defects of the ventral midline, including hypertelorism, cleft lip and palate, heart defects, and mental retardation. We recently identified the gene responsible for X-linked OS. The ubiquitously expressed gene product, MID1, is a member of t...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.96.6.2794
更新日期:1999-03-16 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.90.15.7386
更新日期:1993-08-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.82.9.2703
更新日期:1985-05-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.94.14.7499
更新日期:1997-07-08 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.97.26.14578
更新日期:2000-12-19 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1709203114
更新日期:2017-08-08 00:00:00
abstract::The electrical currents at the surface of the proximal portion of an isolated and transected lamprey spinal cord were measured with an extracellular vibrating probe. Soon after transection, currents of about 0.5 mA/cm2 enter the cut surface of the spinal cord. These currents fall to about a quarter of their initial va...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.77.2.1209
更新日期:1980-02-01 00:00:00
abstract::B-G antigens are cell-surface molecules encoded by a highly polymorphic multigene family located in the chicken major histocompatibility complex (MHC). Rabbit antisera to B-G molecules immunoprecipitate 3-6 bands from iodinated erythrocytes by sodium dodecyl sulfate (SDS) gels under reducing conditions. These are all ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.87.21.8277
更新日期:1990-11-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0909109106
更新日期:2009-12-22 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.77.6.3581
更新日期:1980-06-01 00:00:00
abstract::Traits that enable species to persist in ecological environments are often maintained over time, a phenomenon known as niche conservatism. Here we argue that ecological niches function at levels above species, notably at the level of genus for mammals, and that niche conservatism is also evident above the species leve...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0901648106
更新日期:2009-11-17 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1618551114
更新日期:2017-05-16 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2000-12-19 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.86.24.10029
更新日期:1989-12-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.84.23.8404
更新日期:1987-12-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0603045103
更新日期:2006-07-05 00:00:00
abstract::Classical genetic selection was combined with site-directed mutagenesis to study bacteriophage T4 DNA polymerase 3'----5' exonuclease activity. A mutant DNA polymerase with very little (less than or equal to 1%) 3'----5' exonuclease activity was generated. In vivo, the 3'----5' exonuclease-deficient DNA polymerase pro...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.6.2417
更新日期:1991-03-15 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.261371298
更新日期:2001-12-04 00:00:00
abstract::Coherent oscillations in the theta-to-gamma frequency range have been proposed as a mechanism that coordinates neural activity in large-scale cortical networks in sensory, motor, and cognitive tasks. Whether this mechanism also involves coherent oscillations at delta frequencies (1-4 Hz) is not known. Rather, delta os...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1314681110
更新日期:2013-09-10 00:00:00
abstract::Several cDNA clones encoding the human immunoglobulin G receptor CD16 were isolated from human lung or peripheral blood leukocyte cDNA libraries. Nucleotide sequence comparisons revealed that the cDNAs could be divided into two groups. cDNA clones in one group encode a protein that terminates 4 amino acids after the p...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.86.13.5079
更新日期:1989-07-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.73.1.138
更新日期:1976-01-01 00:00:00
abstract::Unfolded RNase A is known to contain an equilibrium mixture of two forms, a slow-folding form (U(1)) and a fast-folding form (U(2)). If U(1) is produced after unfolding by the slow cis-trans isomerization of proline residues about X-Pro imide bonds, then the formation of U(1) should be catalyzed by strong acids. There...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.75.10.4764
更新日期:1978-10-01 00:00:00
abstract::A comparison of the monoclinic and orthorhombic crystal structures of the uncomplexed double-stranded, antiparallel, left-handed beta-helix (5.6 amino acid residues per turn) (increases decreases beta 5.6) conformers of gramicidin A reveals marked differences in the tryptophan side-chain orientations and the degree of...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.12.5345
更新日期:1991-06-15 00:00:00
abstract::Employing a cell-free chromatin transcription system that recapitulates progesterone receptor (PR)-mediated transcription in vivo, we have investigated further the coactivator functions of steroid receptor coactivator-1 (SRC-1) in terms of its functional domains as well as cooperation with other coactivators in PR tra...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.231474798
更新日期:2001-10-23 00:00:00