Abstract:
:The species-area relationship (SAR) gives a quantitative description of the increasing number of species in a community with increasing area of habitat. In conservation, SARs have been used to predict the number of extinctions when the area of habitat is reduced. Such predictions are most needed for landscapes rather than for individual habitat fragments, but SAR-based predictions of extinctions for landscapes with highly fragmented habitat are likely to be biased because SAR assumes contiguous habitat. In reality, habitat loss is typically accompanied by habitat fragmentation. To quantify the effect of fragmentation in addition to the effect of habitat loss on the number of species, we extend the power-law SAR to the species-fragmented area relationship. This model unites the single-species metapopulation theory with the multispecies SAR for communities. We demonstrate with a realistic simulation model and with empirical data for forest-inhabiting subtropical birds that the species-fragmented area relationship gives a far superior prediction than SAR of the number of species in fragmented landscapes. The results demonstrate that for communities of species that are not well adapted to live in fragmented landscapes, the conventional SAR underestimates the number of extinctions for landscapes in which little habitat remains and it is highly fragmented.
journal_name
Proc Natl Acad Sci U S Aauthors
Hanski I,Zurita GA,Bellocq MI,Rybicki Jdoi
10.1073/pnas.1311491110subject
Has Abstractpub_date
2013-07-30 00:00:00pages
12715-20issue
31eissn
0027-8424issn
1091-6490pii
1311491110journal_volume
110pub_type
杂志文章abstract::Two prominent timekeeping systems, the cell cycle, which controls cell division, and the circadian system, which controls 24-h rhythms of physiology and behavior, are found in nearly all living organisms. A distinct feature of circadian rhythms is that they are temperature-compensated such that the period of the rhyth...
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.0914078107
更新日期:2010-05-25 00:00:00
abstract::A subpopulation of phenobarbital-induced cytochrome P-450 in rat liver has been shown to consist of four closely related forms of the enzyme that appeared to be strain-related. In the present study, polypeptides composing this family were analyzed by two-dimensional electrophoresis of hepatic microsomes from 64 indivi...
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.80.21.6542
更新日期:1983-11-01 00:00:00
abstract::We have constructed bovine papilloma virus recombinants carrying a hybrid gene in which human growth hormone structural sequences are fused to the promoter and presumptive control region of the mouse metallothionein-I gene. Mouse cells transformed with the recombinants synthesize metallothionein-growth hormone hybrid ...
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.80.2.397
更新日期:1983-01-01 00:00:00
abstract::The SCF ubiquitin ligase complex of budding yeast triggers DNA replication by catalyzing ubiquitination of the S phase cyclin-dependent kinase inhibitor SIC1. SCF is composed of three proteins-ySKP1, CDC53 (Cullin), and the F-box protein CDC4-that are conserved from yeast to humans. As part of an effort to identify co...
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.95.13.7451
更新日期:1998-06-23 00:00:00
abstract::To elucidate the molecular mechanism of frameshift suppression by the SUF2 gene of yeast, the sequences of DNA fragments carrying the SUF2-1 and suf2+ alleles of the gene and surrounding regions have been determined. Comparison of the suppressor and wild-type sequences indicates that the SUF2 gene product is a proline...
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.79.11.3565
更新日期:1982-06-01 00:00:00
abstract::The influx of Ca2+ ions controls many important processes in excitable cells, including the regulation of the gating of Ca(2+)-activated K+ channels (the current IK[Ca]). Various IK[Ca] channels contribute to the regulation of the action-potential waveform, the repetitive discharge of spikes, and the secretion of neur...
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.91.7.2858
更新日期:1994-03-29 00:00:00
abstract::Nonenzymatic manganese was first shown to provide protection against superoxide toxicity in vivo in 1981, but the chemical mechanism responsible for this protection subsequently became controversial due to conflicting reports concerning the ability of Mn to catalyze superoxide disproportionation in vitro. In a recent ...
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.1203051109
更新日期:2012-05-01 00:00:00
abstract::Cell aggregation in Dictyostelium discoideum appears to involve the production and detection of 3':5'-cyclic AMP. Two pertinent catalytic activities have been studied in concentrates from D. discoideum purified 50- to 100-fold. They are (i) adenylate cyclase and (ii) ATP pyrophosphohydrolase. ATP pyrophosphohydrolase ...
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.70.4.1254
更新日期:1973-04-01 00:00:00
abstract::III-V compound semiconductors are widely used for electronic and optoelectronic applications. However, interfacing III-Vs with other materials has been fundamentally limited by the high growth temperatures and lattice-match requirements of traditional deposition processes. Recently, we developed the templated liquid-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.1915786117
更新日期:2020-01-14 00:00:00
abstract::The nucleotide sequence of mitochondrial DNA of a cytoplasmic "petite" mutant of Saccharomyces cerevisiae is reported. The DNA has a repeat length of 1060 base pairs and contains a genetic marker (oli-1) for the ATPase proteolipid. The nucleotide sequence reveals the presence of part of the structural gene of the subu...
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.76.1.131
更新日期:1979-01-01 00:00:00
abstract::The calcium-activated K(+) channel KCa3.1 plays an important role in T lymphocyte Ca(2+) signaling by helping to maintain a negative membrane potential, which provides an electrochemical gradient to drive Ca(2+) influx. To assess the role of KCa3.1 channels in lymphocyte activation in vivo, we studied T cell function ...
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.0910133107
更新日期:2010-01-26 00:00:00
abstract::The two nitrile groups at the wings of the nonnucleoside HIV-1 reverse transcriptase (RT) inhibitor TMC278 are both identified in high-sensitivity 2D IR spectroscopy experiments of the HIV-1 RT/TMC278 complex. The vibrational spectra indicate that the two arms of the inhibitor sense quite different environments within...
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.0709320104
更新日期:2008-02-05 00:00:00
abstract::The gene encoding the receptor for hyaluronan-mediated motility (RHAMM) is overexpressed in many human cancers. However, it is unclear whether RHAMM plays a causal role in tumor initiation or progression. Using somatic gene transfer in a mouse model of islet cell tumorigenesis, we demonstrate that RHAMM isoform B (RHA...
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.1114022108
更新日期:2011-10-04 00:00:00
abstract::The natural history of follicular lymphoma (FL) is frequently characterized by transformation to a more aggressive diffuse large B cell lymphoma (DLBCL). We compared the gene-expression profiles between transformed DLBCL and their antecedent FL. No genes were observed to increase or decrease their expression in all 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.132253599
更新日期:2002-06-25 00:00:00
abstract::3.L2 T cell receptor transgenic T cells are activated by the 64-76 peptide of the mouse hemoglobin d beta chain [Hb(64-76)], and their response is antagonized by the position 72 alanine substitution of this peptide (A72). To test the effect of this altered peptide ligand (APL) on 3.L2 T cell function in vivo, a transg...
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.95.24.14332
更新日期:1998-11-24 00:00:00
abstract::We have used the newly engineered transposable element Dsg to tag a gene that gives rise to a defective kernel (dek) phenotype. Dsg requires the autonomous element Ac for transposition. Upon excision, it leaves a short DNA footprint that can create in-frame and frameshift insertions in coding sequences. Therefore, we ...
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.1703498114
更新日期:2017-05-16 00:00:00
abstract::Given the widely noted increase in the warming effects of rising greenhouse gas concentrations, it has been unclear why global surface temperatures did not rise between 1998 and 2008. We find that this hiatus in warming coincides with a period of little increase in the sum of anthropogenic and natural forcings. Declin...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 历史文章,杂志文章
doi:10.1073/pnas.1102467108
更新日期:2011-07-19 00:00:00
abstract::Many ecosystems, from vegetation to biofilms, are composed of territorial populations that compete for both nutrients and physical space. What are the implications of such spatial organization for biodiversity? To address this question, we developed and analyzed a model of territorial resource competition. In the mode...
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.1911570116
更新日期:2019-09-03 00:00:00
abstract::The reported isolation of nanobacteria from human kidney stones raises the intriguing possibility that these microorganisms are etiological agents of pathological extraskeletal calcification [Kajander, E. O. & Ciftçioglu, N. (1998) Proc. Natl. Acad. Sci. USA 95, 8274-8279]. Nanobacteria were previously isolated from F...
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.97.21.11511
更新日期:2000-10-10 00:00:00
abstract::The immunity protein to colicin A (Cai), which is constitutively expressed at a very low level in Escherichia coli strains, has been studied in recombinant plasmid constructs allowing expression of various immunity fusion proteins under the control of inducible promoters. The 13-amino acid NH2-terminal region of Cai w...
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.85.3.689
更新日期:1988-02-01 00:00:00
abstract::Simulations with a regional chemical transport model show that anthropogenic emissions of volatile organic compounds and nitrogen oxides (NO(x) = NO + NO(2)) lead to a dramatic diurnal variation of surface ozone (O(3)) in Houston, Texas. During the daytime, photochemical oxidation of volatile organic compounds catalyz...
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.0401484101
更新日期:2004-04-27 00:00:00
abstract::A procedure is described for selection of temperature-sensitive mutants affecting fatty-acid synthesis based upon radiation suicide of wild-type organisms by tritiated acetate selectively incorporated into fatty acids. At 37 degrees , two of the mutants extensively incorporate fatty-acid supplements provided in the me...
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.69.11.3105
更新日期:1972-11-01 00:00:00
abstract::Cathepsin B (CTSB) is overexpressed in tumors of the lung, prostate, colon, breast, and stomach. However, evidence of primary genomic alterations in the CTSB gene during tumor initiation or progression has been lacking. We have found a novel amplicon at 8p22-23 that results in CTSB overexpression in esophageal adenoca...
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.95.21.12410
更新日期:1998-10-13 00:00:00
abstract::Genomic clones of the human non-N-methyl-D-aspartate (non-NMDA) glutamate receptor subunit GluR5 were isolated by high-stringency screening of a cosmid library using the rat cDNA as a probe. The chromosomal localization of the human GluR5 gene has been established. Southern hybridization of DNA isolated from mapping 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.90.1.178
更新日期:1993-01-01 00:00:00
abstract::Serological expression cloning of antigens eliciting a humoral immune response to a syngeneic mouse sarcoma identified pem (mouse placenta and embryonic expression gene) as a new member of the cancer/testis family. To identify the human homologue of pem, mouse pem sequences and pem-related expressed sequence tags from...
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.041625098
更新日期:2001-03-13 00:00:00
abstract::Utilizing the bicistronic reporter transposon mini-Tn5 lacZ-tet/1, we have identified lacZ fusions to four Escherichia coli genes/operons that are strongly activated by the accumulation of self-produced extracellular signals. These fusions were designated cma9, cma48, cma113, and cma114 for conditioned medium activate...
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.96.8.4610
更新日期:1999-04-13 00:00:00
abstract::Helicases are molecular motor enzymes that unwind and translocate nucleic acids. One of the central questions regarding helicase activity is whether the process of coupling ATP hydrolysis to DNA unwinding requires an oligomeric form of the enzyme. We have applied a pre-steady-state kinetics approach to address this qu...
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.232401899
更新日期:2002-11-12 00:00:00
abstract::Epigenetic mechanisms are involved in the pathophysiology of depressive disorders and are unique potential targets for therapeutic intervention. The acetylating agent L-acetylcarnitine (LAC), a well-tolerated drug, behaves as an antidepressant by the epigenetic regulation of type 2 metabotropic glutamate (mGlu2) recep...
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.1216100110
更新日期:2013-03-19 00:00:00
abstract::Theoretical models suggest that social networks influence the evolution of cooperation, but to date there have been few experimental studies. Observational data suggest that a wide variety of behaviors may spread in human social networks, but subjects in such studies can choose to befriend people with similar behavior...
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.0913149107
更新日期:2010-03-23 00:00:00
abstract::Molecular dynamics (MD) simulations provide essential information about the thermodynamics and dynamics of proteins. To construct the free-energy surface from equilibrium trajectories, it is necessary to group the individual snapshots in a meaningful way. The inherent structures (IS) are shown to provide an appropriat...
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.0915087107
更新日期:2010-05-18 00:00:00