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991.
992.
Many researchers have questioned the ability of biota to adapt to rapid anthropogenic environmental shifts. Here, we synthesize emerging genomic evidence for rapid insect evolution in response to human pressure. These new data reveal diverse genomic mechanisms (single locus, polygenic, structural shifts; introgression) underpinning rapid adaptive responses to a variety of anthropogenic selective pressures. While the effects of some human impacts (e.g. pollution; pesticides) have been previously documented, here we highlight startling new evidence for rapid evolutionary responses to additional anthropogenic processes such as deforestation. These recent findings indicate that diverse insect assemblages can indeed respond dynamically to major anthropogenic evolutionary challenges. Our synthesis also emphasizes the critical roles of genomic architecture, standing variation and gene flow in maintaining future adaptive potential. Broadly, it is clear that genomic approaches are essential for predicting, monitoring and responding to ongoing anthropogenic biodiversity shifts in a fast-changing world. 相似文献
993.
Sara E. Cannon Simon D. Donner Angela Liu Pedro C. González Espinosa Andrew H. Baird Julia K. Baum Andrew G. Bauman Maria Beger Cassandra E. Benkwitt Matthew J. Birt Yannick Chancerelle Joshua E. Cinner Nicole L. Crane Vianney Denis Martial Depczynski Nur Fadli Douglas Fenner Christopher J. Fulton Yimnang Golbuu Nicholas A. J. Graham James Guest Hugo B. Harrison Jean-Paul A. Hobbs Andrew S. Hoey Thomas H. Holmes Peter Houk Fraser A. Januchowski-Hartley Jamaluddin Jompa Chao-Yang Kuo Gino Valentino Limmon Yuting V. Lin Timothy R. McClanahan Dominic Muenzel Michelle J. Paddack Serge Planes Morgan S. Pratchett Ben Radford James Davis Reimer Zoe T. Richards Claire L. Ross John Rulmal Jr. Brigitte Sommer Gareth J. Williams Shaun K. Wilson 《Global Change Biology》2023,29(12):3318-3330
Scientists and managers rely on indicator taxa such as coral and macroalgal cover to evaluate the effects of human disturbance on coral reefs, often assuming a universally positive relationship between local human disturbance and macroalgae. Despite evidence that macroalgae respond to local stressors in diverse ways, there have been few efforts to evaluate relationships between specific macroalgae taxa and local human-driven disturbance. Using genus-level monitoring data from 1205 sites in the Indian and Pacific Oceans, we assess whether macroalgae percent cover correlates with local human disturbance while accounting for factors that could obscure or confound relationships. Assessing macroalgae at genus level revealed that no genera were positively correlated with all human disturbance metrics. Instead, we found relationships between the division or genera of algae and specific human disturbances that were not detectable when pooling taxa into a single functional category, which is common to many analyses. The convention to use percent cover of macroalgae as an indication of local human disturbance therefore likely obscures signatures of local anthropogenic threats to reefs. Our limited understanding of relationships between human disturbance, macroalgae taxa, and their responses to human disturbances impedes the ability to diagnose and respond appropriately to these threats. 相似文献
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995.
996.
Three forms of cytochrome c oxidase, fully oxidized CcO (CcO-O), oxidized CcO complexed with cyanide (CcO.CN), and mixed valence CcO, in which both heme a(3) and Cu(B) are reduced and stabilized by carbon monoxide (MV.CO), were investigated by optical spectroscopy, MCD, and stopped-flow for the pH sensitivity of spectral features. In the pH range between pH 5.7 and 9.0, both heme a and heme a(3) in CcO-O interact with a single protolytic group. From the variation of the position of the Soret peak with changes in pH, a pK(a) of 6.6 +/- 0.2 was determined for this group. The pH sensitivity of heme a(3) is lost in the CcO.CN complex, and only heme a responds to pH changes. In MV.CO the spectra of both hemes are almost independent of pH between 5.7 and 11.0. The stoichiometry of proton uptake in the conversion of CcO-O both to MV.CO and to fully reduced CcO was determined between pH 5.8 and pH 8.2. Formation of MV.CO from CcO-O was accompanied by the uptake of approximately two protons, and this value was almost independent of pH. Full reduction of oxidized CcO was associated with the uptake of approximately 2 H(+) at basic pH, and this value increases with decreasing pH. On the basis of these proton uptake measurements, it is concluded that the pK(a) of the group is independent of the redox state of CcO. It is suggested that Glu60 of subunit II, located at the entrance of the proton conducting K-channel, is the protolytic residue that interacts with both hemes through a hydrogen-bonding network. 相似文献
997.
Graham D. Raby Lee F. G. Gutowsky Michael G. Fox 《Environmental Biology of Fishes》2010,89(2):143-150
We assessed density, gut fullness and prey composition of round goby (Neogobius melanostomus) from three areas in the Trent River (Ontario) representing areas of initial introduction and subsequent expansion. Round
goby had been present at the area of original introduction since 2003, and by 2007/2008, their range had expanded upstream
and downstream into the outermost reaches sampled in the study. Catch per unit angling effort in nearshore sites indicated
that round goby density in the area of original introduction was more than double their density in the upstream expansion
area and nearly three times the density in the downstream expansion area. Gut fullness index was lower in gobies from the
area of original introduction than for those at the upstream and downstream edges of their expanded range. The most dramatic
difference in diet composition was with dreissenids, where large gobies (≥70 mm) occupying the area of original introduction
had almost no dreissenid biomass in their guts, whereas dreissenids were the predominant prey type in gobies occupying the
two expansion areas. Post-hoc zebra mussel density in the area of original introduction was an order of magnitude lower than
in the two expansion areas which, combined with the differences in stomach fullness and prey composition, suggest that local,
density-related reduction of this prey type was occurring in the river. 相似文献
998.
Michael J. Sweredoski Geoffrey T. Smith Anastasia Kalli Robert L. J. Graham Sonja Hess 《Journal of biomolecular techniques》2011,22(4):122-126
Visualization tools that allow both optimization of instrument''s parameters for data acquisition and specific quality control (QC) for a given sample prior to time-consuming database searches have been scarce until recently and are currently still not freely available. To address this need, we have developed the visualization tool LogViewer, which uses diagnostic data from the RAW files of the Thermo Orbitrap and linear trap quadrupole-Fourier transform (LTQ-FT) mass spectrometers to monitor relevant metrics. To summarize and visualize the performance on our test samples, log files from RawXtract are imported and displayed. LogViewer is a visualization tool that allows a specific and fast QC for a given sample without time-consuming database searches. QC metrics displayed include: mass spectrometry (MS) ion-injection time histograms, MS ion-injection time versus retention time, MS2 ion-injection time histograms, MS2 ion-injection time versus retention time, dependent scan histograms, charge-state histograms, mass-to-charge ratio (M/Z) distributions, M/Z histograms, mass histograms, mass distribution, summary, repeat analyses, Raw MS, and Raw MS2. Systematically optimizing all metrics allowed us to increase our protein identification rates from 600 proteins to routinely determine up to 1400 proteins in any 160-min analysis of a complex mixture (e.g., yeast lysate) at a false discovery rate of <1%. Visualization tools, such as LogViewer, make QC of complex liquid chromotography (LC)-MS and LC-MS/MS data and optimization of the instrument''s parameters accessible to users. 相似文献
999.
Bedell JA Budiman MA Nunberg A Citek RW Robbins D Jones J Flick E Rholfing T Fries J Bradford K McMenamy J Smith M Holeman H Roe BA Wiley G Korf IF Rabinowicz PD Lakey N McCombie WR Jeddeloh JA Martienssen RA 《PLoS biology》2005,3(1):e13
1000.
S. Goya Wannamethee Alison E. Field Graham A. Colditz Eric B. Rimm 《Obesity (Silver Spring, Md.)》2004,12(9):1386-1396
Objective: To examine prospectively the relationship between alcohol and 8‐year weight gain in women. Research Methods and Procedures: A prospective study of 49, 324 women 27 to 44 years old who did not have a history of cardiovascular disease, cancer, or diabetes, who were not pregnant during the study period, and who reported weights in 1991 and 1999. Results: In cross‐sectional analyses, there was a significant inverse relationship between alcohol and BMI even after adjustment for dietary factors and a wide range of confounders. In multivariate prospective analyses, a nonlinear relationship was seen between alcohol and weight gain (≥5 kg) in all women. Compared with nondrinkers, the adjusted relative odds [95% confidence interval (CI)] of weight gain according to grams per day were 0.94 (0.89, 0.99) for those consuming 0.1 to 4.9 g/d, 0.92 (0.85, 0.99) for 5 to 14.9 g/d, 0.86 (0.76, 0.78) for 15 to 29.9 g/d, and 1.07 (0.89, 1.28) for those consuming 30+ g/d (p < 0.0001 for quadratic trend). Women who continued to drink heavily and those who became heavy drinkers showed similar increased odds of weight gain. The increased odds of weight gain associated with heavy drinking (30+ g/d) were most marked in the younger women (<35 years) (odds ratio 1.64; 5% CI 1.03 to 2.61). In African‐American women, light drinking was associated with increased odds of weight gain compared with nondrinkers (odds ratio = 2.43; 95% CI 1.22 to 4.82) Discussion: Our data suggest that light to moderate drinking (up to 30 g/d) is not associated with weight gain in women except possibly in African‐American women. Heavier drinking may promote weight gain in women. 相似文献