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A comparison of two methods to assess audience-induced changes in male mate choice

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Current Zoology 2012年第1期58卷 84-94页

作者： Madlen ZIEGE Carmen HENNIGE-SCHULZ Frauke MUECKSCH Department of Ecology & Evolution J. W. Goethe University Frankfurt institute of Biochemistry & biology Unit of Evolutionary Biology & Systematic Zoology University of Potsdam

Multidirectional communicative interactions in social networks can have a profound effect on mate choice behavior. Male Atlantic molly Poecilia mexicana exhibit weaker mating preferences when an audience male is presented. This could be a male strategy to reduce sperm competition risk： interacting more equally with different females may be advantageous because ri- vals might copy mate choice decisions. In line with this hypothesis, a previous study found males to show a strong audience effect when being observed while exercising mate choice, but not when the rival was presented only before the choice tests. Audience effects on mate choice decisions have been quantified in poeciliid fishes using association preference designs, but it remains un- known if patterns found from measuring association times translate into actual mating behavior. Thus, we created five audience treatments simulating different forms of perceived sperm competition risk and determined focal males＇ mating preferences by scoring pre-mating （nipping） and mating behavior （gonopodial thrusting）. Nipping did not reflect the pattern that was found when association preferences were measured, while a very similar pattern was uncovered in thrusting behavior. The strongest response was observed when the audience could eavesdrop on the focal male＇s behavior. A reduction in the strength of focal males＇ preferences was also seen after the rival male had an opportunity to mate with the focal male＇s preferred mate. In comparison, the reduction of mating preferences in response to an audience was greater when measuring association times than actual mating behavior. While measuring direct sexual interactions between the focal male and both slimulus females not only the male＇s motivational state is reflected but also females＇ behavior such as avoidance of male sexual harassment [Current Zoology 58 （1）： 84-94, 2012].

关键词： Communication networks Male mate choice Non-independent mate choice Sexual selection Sperm competition risk Audience effect

Previous encapsulation response enhances within individual protection against fungal parasite in the mealworm beetle Tenebrio mofitor

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Insect Science 2013年第6期20卷 771-777页

作者： Indrikis Krams Janina Daukste Inese Kivleniece Tatjana Krama Markus J. Rantala institute of Ecology and Earth Sciences University of Tartu Tartu Estonia institute of systematic biology University of Daugavpils Daugavpils institute of Food Safety Animal Health and Environment BIOR Riga Latvia Department of biology University of Turku Turku Finland

Immune defenses of insects show either broad reactions or specificity and durability of induced protection against attacking parasites and pathogens. In this study, we tested whether encapsulation response against nylon monofilament increases between two attempts of activation of immune system in mealworm beetles Tenebrio molitor, and whether previous exposure to nylon monofilament may also increase protection against an entomopathogenic fungus. We found that survival of beetles subjected to immune activation by nylon implant and subsequent fungal exposure a week later was significantly higher than survival of beetles which had been subjected to fimgal infection only. This result suggests that previous immune activation by the nylon implant may be considered as broad spectrum ＂immune priming＂ which helps to fight not only the same intruder but also other parasites.

关键词： antifungal protection ecological immunology encapsulation response,immune priming invertebrate immunity Tenebrio molitor

A fossil-calibrated relaxed clock for Ephedra indicates an Oligocene age for the divergence of Asian and New World clades and Miocene dispersal into South America

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Journal of systematics and Evolution 2009年第5期47卷 444-456页

作者： Stefanie M.ICKERT-BOND Catarina RYDIN Susanne S.RENNER University of Alaska UA Museum of the North Herbarium and Institute of Arctic Biology institute of systematic Botany University of Zurich University of Munich Systematic Botany and Mycology

Ephedra comprises approximately 50 species,which are roughly equally distributed between the Old and New World deserts,but not in the intervening regions(amphitropical range).Great heterogeneity in the substitution rates of Gnetales(Ephedra,Gnetum,and Welwitschia) has made it difficult to infer the ages of the major divergence events in Ephedra,such as the timing of the Beringian disjunction in the genus and the entry into South ***,we use data from as many Gnetales species and genes as available from GenBank and from a recent study to investigate the timing of the major divergence *** of the tradeoff between the amount of missing data and taxon/gene sampling,we reduced the initial matrix of 265 accessions and 12 loci to 95 accessions and 10 loci,and further to 42 species(and 7736 aligned nucleotides) to achieve stationary distributions in the Bayesian molecular clock *** from a relaxed clock with an uncorrelated rates model and fossil-based calibration reveal that New World species are monophyletic and diverged from their mostly Asian sister clade some 30 mya,fitting with many other Beringian *** split between the single North American and the single South American clade occurred approximately 25 mya,well before the closure of the Panamanian ***,the biogeographic history of Ephedra appears dominated by long-distance dispersal,but finer-scale studies are needed to test this hypothesis.

关键词： biogeography Ephedra relaxed molecular clock dating uncorrelated rates model.

ABC model and floral evolution

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Chinese Science Bulletin 2003年第24期48卷 2651-2657页

作者： LI Guisheng, MENG Zheng, KONG Hongzhi, CHEN Zhiduan & LU Anming Laboratory of systematic and Evolutionary Botany, institute of Botany, Chinese Academy of Sciences, Beijing 100093, China Correspondence should be addressed to Meng Zheng (e-mail: zhmeng@ ***) and Lu Anming (e-mail:anmin@***) Laboratory of systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences

The paper introduces the classical ABC model of floral development and thereafter ABCD, ABCDE and quartet models, and presents achievements in the studies on floral evolution such as the improved understanding on the relationship of reproductive organs between gnetophytes and angiosperms, new results in perianth evolution and identified homology of floral organs between dicots and monocots. The evo-devo studies on plant taxa at different evolutionary levels are useful to better understanding the homology of floral organs, and to clarifying the mysteries of the origin and sub-sequent diversification of flowers.

关键词： ABC模型花被演化被子植物双子叶植物单子叶植物

Seasonal and Tissue Age Influences on Endophytic Fungi of Pinus tabulaeformis (Pinaceae) in the Dongling Mountains, Beijing

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Journal of Integrative Plant biology 2008年第8期50卷 997-1003页

作者： Liang-Dong Guo Guo-Rui Huang Yu Wang systematic Mycology and Lichenology Laboratory Institute of Microbiology the Chinese Academy of Sciences Beijing 100101 China

Endophytic fungi associated with Pinus tabulaeformis Carr. were investigated in the Dongling Mountains of Beijing. A total of 16200 tissue segments of P. tabulaeformis from four sample collections were processed, and 10659 fungal isolates were recovered. The overall colonization and isolation rates of endophytic fungi from high to low were spring〉winter〉autumn〉summer and in different tissues were bark〉needle〉xylem, irrespective of sampling seasons. The colonization rates of endophytic fungi of needles increased with age in the four sample collections. There were no significant differences of the colonization rates of endophytic fungi among 1-, 2-, and 3-year-old bark and xylem, except for significantly lower colonization rates in 1-year-old bark than in 2- and 3-year-old bark in summer. A similar trend of the isolation rates of endophytic fungi occurred. A total of 24 fungal taxa were recorded, of these five taxa Alternaria alternata, Leptostroma sp., Pestalotiopsis besseyi, Phoma lingam, and Phomopsis archeri, were consistently isolated as the common fungi in each sample collection. Our results suggest that some fungi show a certain degree of tissue recurrence or specificity, and the composition of endophytic assemblages is not conspicuously influenced by the seasonal factor.

关键词： colonization and isolation rates endophyte pine season tissue

Plants of Leptostrobus Heer （Czekanowskiales） from the Early Cretaceous and Late Triassic of China, with Discussion of the Genus

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Journal of Integrative Plant biology 2006年第2期48卷 137-147页

作者： Xiu-Qun Liu Cheng-Sen Li Yu-Fei Wang Laboratory of systematic and Evolutionary Botany Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

Investigation of the Mesozoic seed plant Leptostrobus Heer from the Yangcaogou Formation of the Late Triassic and the Yixian Formation of the Early Cretaceous, Liaoning Province, China, provides new Insight Into Its general morphology and geographical distribution. The materials of L. cancer from the Yixian Formation described herein are later than all the past findings of this species and add to the record of L. cancer during the Early Cretaceous. Based on well-preserved specimens, the specific diagnosis Is slightly emended and the reconstructlon of L. cancer Is perfected. The materials from the Yangcaogou Formation of the Late Triassic are placed in L. spheericus, in addition, we review the history of investigation of the genus Leptostrobus since its establishment in 1876 and discuss the main characteristics of each species.

关键词： Early Cretaceous Late Triassic Leptostrobus Yangcaogou Formation Yixian Formation.

Pollen Morphology of the Platycodonoid Group (Campanulaceae ***.) and Its systematic Implications

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Journal of Integrative Plant biology 2012年第10期54卷 773-789页

作者： HONG De-Yuan PAN Kai-Yu State Key Laboratory of systematic&Evolutionary Botany Institute of BotanyThe Chinese Academy of SciencesChina

In this study, we examined the pollen morphology of the platycodonoid group in Campanulaceae s. str. using a scanning electronic microscope. We used pollen grains of 25 accessions representing 24 species of the Codonopsis complex （including Campanumoea, Cyclocodon, Leptocodon, and all three subgenera of Codonopsis）, which is extremely controversial among authors for taxonomic treatment. Pollen morphology of all the other genera in the group observed by previous authors is taken into account in our discussion. A total of nine pollen types with two subtypes in the group were recognized and named for the first time. Molecular and morphological data imply that each pollen type corresponds to a natural group at generic level, and thus the mergence of Leptocodon with Codonopsis and the restoration of Cyclocodon as a separate genus are justifiable, and Codonopsis subg. Pseudocodonopsis, subg. Obconicicapsula, and two species of Codonopsis subg. Codonopsis （C. purpurea and C. chimiliensis） may be better classified as three independent genera separate from the core Codonopsis.

关键词： Campanulaceae s. str. platycodonoid group Codonopsis complex pollen morphology pollen type taxonomy systematics.

The Puzzle of Rice Domestication

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Journal of Integrative Plant biology 2007年第6期49卷 760-768页

作者： Tao Sang Song Ge Department of Plant biology Michigan State University East Lansing MI 48824 USA State Key Laboratory of systematic and Evolutionary Botany the Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

The origin of cultivated rice has puzzled plant biologists for decades. This is due, at least in part, to the complex evolutionary dynamics in rice cultivars and wild progenitors, particularly rapid adaptive differentiation and continuous gene flow within and between cultivated and wild rice. The long-standing controversy over single versus multiple and annual versus perennial origins of cultivated rice has been brought into shaper focus with the rapid accumulation of genetic and phylogenetic data. Molecular phylogenetic analyses revealed ancient genomic differentiation between rice cultivars, suggesting that they were domesticated from divergent wild populations. However, the recently cloned domestication gene sh4, responsible for the reduction of grain shattering from wild to cultivated rice, seems to have originated only once. Herein, we propose two models to reconcile apparently conflicting evidence regarding rice domestication. The snowoballing model considers a single origin of cultivated rice. In this model, a core of critical domestication alleles was fixed in the founding cultivar and then acted to increase the genetic diversity of cultivars through hybridization with wild populations. The combination model considers multiple origins of cultivated rice. In this model, Initial cultivars were domesticated from divergent wild populations and fixed different sets of domestication alleles. Subsequent crosses among these semi-domesticated cultivars resulted in the fixation of a similar set of critical domestication alleles in the contemporary cultivars. In both models, introgression has played an important role in rice domestication. Recent and future introgression of beneficial genes from the wild gene pool through conventional and molecular breeding programs can be viewed as the continuation of domestication.

关键词： Oryza sativa Oryza rufipogon Oryza nivara phylogeny population genetics QTL shattering sh4.

Analysis of plastid and nuclear DNA data in plant phylogenetics——evaluation and improvement

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Science China(Life Sciences) 2014年第3期57卷 280-286页

作者： WANG Wei LI HongLei CHEN ZhiDuan State Key Laboratory of systematic and Evolutionary Botany Institute of BotanyChinese Academy of Sciences

Correct combination of plastid(cp)and nuclear(nr)DNA data for plant phylogenetic reconstructions is not a new issue,but with an increasing number of nrDNA loci being used,it is of ever greater practical *** accurately reconstructing the phylogeny and evolutionary history of plant groups,correct treatment of phylogenetic incongruence is a vital step in the proper analysis of cpDNA and nrDNA *** first evaluated the current status of analyzing cpDNA and nrDNA data by searching all articles published in the journal systematic Botany between 2005 and *** studies combining cpDNA and nrDNA data did not rigorously assess the combinability of the data sets,or did not address in detail possible reasons for incongruence between the two data *** reviewing various methods,we outline a procedure to more accurately analyze and/or combine cpDNA and nrDNA data,which includes four steps:identifying significant incongruence,determining conflicting taxa,providing possible interpretations for incongruence,and reconstructing the phylogeny after treating *** attention is given to explanation of the cause of *** hope that our procedure will help raise awareness of the importance of rigorous analysis and help identify the cause of incongruence before combining cpDNA and nrDNA data.

关键词： combined analysis plastid DNA incongruence nuclear DNA phylogenetics