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Physiological and Growth Responses of C_3 and C_4 Plants to Reduced Temperature When Grown at Low CO_2 of the Last Ice Age

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Journal of Integrative Plant Biology 2008年第11期50卷 1388-1395页

作者： Joy K.Ward David A.Myers Richard B.Thomas Department of ecology and evolutionary Biology University of Kansas Department of Biology West Virginia University

During the last ice age, CO2 concentration （[CO2]） was 180-200 umol/mol compared with the modern value of 380 umol/mol, and global temperatures were -8 ℃ cooler. Relatively little is known about the responses of C3 and C4 species to longterm exposure to glacial conditions. Here Abutilon theophrasti Medik. （C3） and Amaranthus retroflexus L. （C4） were grown at 200 umol/mol CO2 with current （30/24℃） and glacial （22/16℃） temperatures for 22d. Overall, the C4 species exhibited a large growth advantage over the C3 species at low [CO2]. However, this advantage was reduced at low temperature, where the C4 species produced 5x the total mass of the C3 species versus 14x at the high temperature. This difference was due to a reduction in C4 growth at low temperature, since the C3 species exhibited similar growth between temperatures. Physiological differences between temperatures were not detected for either species, although photorespiration/net photosynthesis was reduced in the C3 species grown at low temperature, suggesting evidence of improved carbon balance at this treatment. This system suggests that C4 species had a growth advantage over C3 species during low [CO2] of the last ice age, although concurrent reductions in temperatures may have reduced this advantage.

关键词： Abutilon theophrasti Amaranthus retroflexus C3 species C4 species climate change low CO2 low temperature photorespiration Pleistocene.

Forget-me-not： Complex floral displays, inter-signal interactions, and pollinator cognition

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Current Zoology 2011年第2期57卷 215-224页

作者： Anne S. LEONARD Anna DORNHAUS Daniel R. PAPAJ Center for Insect Science / Department of ecology and evolutionary Biology University of Arizona Tucson AZ 85721 USA

Flowers are multisensory displays used by plants to influence the behavior of pollinators. Although we know a great deal about how individual signal components are produced by plants and detected or learned by pollinators, very few experiments directly address the function of floral signal complexity, i.e. how the multicomponent nature of these signals benefits plant or pollinator. Yet, experimental psychology suggests that increasing complexity can enhance subjects＇ ability to detect, learn and remember stimuli, and the plant＇s reproductive success depends upon ensuring that pollinators learn their signals and so transport pollen to other similar （conspecific） flowers. Here we explore functional hypotheses for why plants invest in complex floral displays, focusing on hypotheses in which floral signals interact to promote pollinator learning and memory. Specifically, we discuss how an attention-altering or context-providing function of one signal may promote acquisition or recall of a second signal. Although we focus on communication between plants and pollinators, these process-based hypotheses should apply to any situation where a sender benefits from enhancing a receiver＇s acquisition or recall of information .

关键词： Multimodal signal Learning Attention Bee Context Flower

Studying the genetic basis of speciation in high gene flow marine invertebrates

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Current Zoology 2016年第6期62卷 643-653页

作者： Grant H. POGSON Department of ecology and evolutionary Biology University of California Santa Cruz CA 95064 USA

A growing number of genes responsible for reproductive incompatibilities between species （barrier loci） exhibit the signals of positive selection. However, the possibility that genes experiencing positive selection diverge early in speciation and commonly cause reproductive incompatibilities has not been systematically investigated on a genome-wide scale. Here, I outline a research program for studying the genetic basis of speciation in broadcast spawning marine invertebrates that uses a priori genome-wide information on a large, unbiased sample of genes tested for positive selection. A targeted sequence capture approach is proposed that scores single-nucleotide polymorphisms （SNPs） in widely separated species populations at an early stage of allopatric divergence. The targeted capture of both coding and non-coding sequences enables SNPs to be characterized at known locations across the genome and at genes with known selective or neutral histories. The neutral coding and non-coding SNPs provide robust background distributions for identifying Fsm-outliers within genes that can, in principle, identify specific mutations experiencing diversifying selection. If natural hybridization occurs between species, the neutral coding and noncoding SNPs can provide a neutral admixture model for genomic clines analyses aimed at finding genes exhibiting strong blocks to introgression. Strongylocentrotid sea urchins are used as a model system to outline the approach but it can be used for any group that has a complete reference genome available.

关键词： barrier loci Bobzhansky-Muller incompatibilities FsToutliers genome scan introgression positive selection sequence capture speciation.

Effect of mate size on maternal reproductive effort in the convict cichlid Amatitlania siquia

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Current Zoology 2012年第1期58卷 66-72页

作者： Robart, Ashley R. Department of ecology and evolutionary Biology University of California Santa Cruz CA 95064 USA

The differential allocation hypothesis predicts individuals will increase their reproductive investment when mated to a high quality partner. In many species of fish with biparental care females prefer large males due to the males＇ greater ability to raise more offspring to independence. I examined the relationship between mate quality, parental care and number of offspring in a natural population of convict cichlids Amatitlania siquia. The frequency of frontal displays by females was positively correlated with male standard length. Additionally, as males increased in length relative to their mate, females increased the frequency of chases towards predators, while males decreased the number of displays towards brood predators. This trade-off in parental effort within a pair due to mate quality is a key prediction of differential allocation. The number of offspring was correlated with male, but not female, standard length. These results support the differential allocation hypothesis in that females offered more parental care to offspring of a larger male, while their mates decreased the amount of care they provided. AdditionaUy, females benefited in terms of number of offspring by pairing with higher quality mates. Increased female investment may provide an incentive to ensure male care and maintain pair bonding, which could lead to greater reproductive success through increased offspring sur- vival [Current Zoology 58 （1）： 66-72, 2012].

关键词： Differential allocation Biparental care Maternal effort Cichlid

What Has Genomics Taught An evolutionary Biologist?

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Genomics, Proteomics & Bioinformatics 2023年第1期21卷 1-12页

作者： Jianzhi Zhang Department of ecology and evolutionary Biology University of MichiganAnn ArborMI 48109USA

Genomics,an interdisciplinary field of biology on the structure,function,and evolution of genomes,has revolutionized many subdisciplines of life sciences,including my field of evolutionary biology,by supplying huge data,bringing high-throughput technologies,and offering a new approach to *** this review,I describe what I have learned from genomics and highlight the fundamental knowledge and mechanistic insights gained.I focus on three broad topics that are central to evolutionary biology and beyond—variation,interaction,and selection—and use primarily my own research and study subjects as *** the next decade or two,I expect that the most important contributions of genomics to evolutionary biology will be to provide genome sequences of nearly all known species on Earth,facilitate high-throughput phenotyping of natural variants and systematically constructed mutants for mapping genotype–phenotype–fitness landscapes,and assist the determination of causality in evolutionary processes using experimental evolution.

关键词： Variation Interaction Selection Evolution Genetics Mutation

The development of policy approaches for reducing nitro-gen pollution to coastal waters of the USA

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Science China(Life Sciences) 2005年第Z2期48卷 791-806页

作者： Robert W.Howarth Department of ecology & evolutionary Biology Cornell University NY 14853USA

Two-thirds of the coastal rivers and bays in the United States are degraded from nutrient pollution, and nitrogen inputs these waters continue to increase. The nitrogen comes from a variety of sources, including runoff from agricultural fields, concentrated animal feeding operations, atmospheric deposition from fossil fuel combustion, and sewage and septic wastes. Technical solutions for nitrogen pollution exist at reasonable cost. That most of these solutions have not yet been implemented to any significant extent across the United States suggests that new policy approaches are necessary. The best solution may involve a combination of voluntary and mandatory approaches, applying different approaches to different sources of nitrogen pollution. A watershed-based approach that relies heavily on voluntary mechanisms (such as crop-yield insurance to reduce over-fertilization) is likely to be the most effective for some sources of nitrogen (such as runoff from agricultural fields), while a uniform national regulatory approach may be better for others (such as NOx emissions from fossil fuel combustion). Implementation of management strategies should be carefully coupled to monitoring programs to assess the effectiveness of these strategies. While both nitrogen and phosphorus are important to control, the focus should be on nitrogen management, in part because nitrogen is more generally the causal agent of coastal eutrophication. Also, while nitrogen-control practices tend to also reduce phosphorus pollution, phosphorus-control practices often have little effect on nitrogen. Although current scientific and technical knowledge is sufficient to begin to make substantial progress toward solving coastal nitrogen pollution, progress will be made more quickly and more cost effectively with increased investment in appropriate scientific research.

关键词： development of policy approaches, reducing nitrogen pollution, coastal water of the USA.

The dynamics of color signals in male threespine sticklebacks Gasterosteus aculeatus

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Current Zoology 2016年第1期62卷 23-31页

作者： Meike HIERMES Ingolf P. RICK Marion MEHLIS Theo C. M. BAKKER Institute for evolutionary Biology and ecology University of Bonn An der Immenburg 1 53121 Bonn Germany

Body coloration and color patterns are ubiquitous throughout the animal kingdom and vary be- tween and within species. Recent studies have dealt with individual dynamics of various aspects of coloration, as it is in many cases a flexible trait and changes in color expression may be context-de- pendent. During the reproductive phase, temporal changes of coloration in the visible spectral range （400-700 nm） have been shown for many animals but corresponding changes in the ultravio- let （UV） waveband （300-400 nm） have rarely been studied. Threespine stickleback Gasterosteus aculeatus males develop conspicuous orange-red breeding coloration combined with UV reflect- ance in the cheek region. We investigated dynamics of color patterns including UV throughout a male breeding cycle, as well as short-term changes in coloration in response to a computer- animated rival using reflectance spectrophotometry and visual modeling, to estimate how colors would be perceived by conspecifics. We found the orange-red component of coloration to vary during the breeding cycle with respect to hue （theta/R50） and intensity （achieved chroma/red chroma）. Furthermore, color intensity in the orange-red spectral part （achieved chroma） tended to be increased after the presentation of an artificial rival. Dynamic changes in specific measures of hue and intensity in the UV waveband were not found. In general, the orange-red component of the signal seems to be dynamic with respect to color intensity and hue. This accounts in particular for color changes during the breeding cycle, presumably to signal reproductive status, and with limitations as well in the intrasexual context, most likely to signal dominance or inferiority.

关键词： breeding season color change color signals stickleback structural coloration UV coloration

Response of brown anoles Anolis sagrei to multimodal signals from a native and novel predator

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Current Zoology 2012年第6期58卷 791-796页

作者： Omar L. ELMASRI Marcus S. MORENO Courtney A. NEUMANN Daniel T.BLUMSTEIN Department of ecology and evolutionary Biology University of California Los Angeles CA 90095-1606 USA

Abstract Multiple studies have focused on the importance of single modalities （visual, auditory, olfactory） in eliciting anti-predator behavior, however multiple channels are often engaged simultaneously. While examining responses to multiple cues can potentially reveal more complex behavioral responses, little is known about how multimodal processing evolves. By contrasting response to familiar and novel predators, insights can be gained into the evolution of multimodal responses. We studied brown anoles＇（Anolis sagrei） response to acoustic and visual predatory cues of a common potential predator, the great-tailed grackle Quiscalus mexicanus and to the American kestrel Falco sparverius, a species found in other populations but not present in our study population. We observed anole behavior before and after a stimulus and quantified rates of looking, display, and locomotion. Anoles increased their rate of locomotion in response to grackle models, an effect modulated by grackle vocalizations. No such response or modulation was seen when anoles were presented with kestrel stimuli. This suggests that the degree of sophistication of anole response to predators is experience dependent and that relaxed selection can result in reduced anti-predator response following loss of predators.

关键词： Anti-predator behavior Multimodal risk assessment Brown anoles

A test of the species confidence hypothesis in dusky damselfish

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Current Zoology 2024年第1期70卷 79-86页

作者： Elle Overs Sydney Stump Isabel Severino Daniel T.Blumstein Department of ecology and evolutionary Biology University of CaliforniaLos AngelesCA 90095-1606USA

Visual cues are important in both interspecific and intraspecific *** species confidence hypothesis proposes that animals are more attracted to conspecific colors and repelled by colors,not on their *** on terrestrial lizards and birds have tested the species confidence hypothesis and shown that conspecific colors elicit reduced antipredator *** date,the species confidence hypothesis has not been tested in the marine environment,specifically on coral reefs where color communication is of vital *** addressed this knowledge gap by measuring flight initiation distance(the distance an individual moves away from an approaching threat)in dusky damselfish(Stegastes nigricans)in response to an approaching disc of 1 of 4 different color treatments:conspecific,blue,yellow,and *** the species confidence hypothesis explained variation in damselfish flight initiation distance,then we expected individuals to tolerate closer approaches when approached by a conspecific *** addition,we calculated the color difference between each stimulus and its corresponding back-ground as a potential alternative explanation for flight *** tolerated the closest approach from the conspecific color stimulus;there were no significant differences between other colors and there was no support for the alternative color difference *** with similar terrestrial studies,these results are relevant to ecotourists'choice of swimsuit and wetsuit colors because color choice may modify naturalantipredatorbehavior.

关键词： antipredator behavior flight initiation distance risk assessment species confidence hypothesis Stegastes nigricans