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151.
MARIA CRISTINA LORENZI MARCO CALDI RITA CERVO 《Biological journal of the Linnean Society. Linnean Society of London》2007,91(3):505-512
Polistes foundresses can behave as facultative social parasites when, instead of founding their own nest, they usurp colonies of the same or a different species and temporary use the host workforce to raise their own brood. Conspecific usurpation appears to be common among Polistes wasps, but nothing is known about the mechanisms that these facultative social parasites use to have themselves accepted within usurped colonies. Using behavioural tests, we studied the chemical strategies employed by females of Polistes nimphus when they behave as facultative social parasites in colonies of the same or of a different species. We hypothesized that usurpers would mark host nests with their own odours and/or acquire host nest odours in order to camouflage their real identity from host workers. Our results indicated that P. nimphus usurpers used different chemical strategies depending on host nest species: they acquired conspecific host odours but marked heterospecific host combs with their own odours. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 505–512. 相似文献
152.
HIROTAKE ONO YOKO KAWA MARIA SANO MASARU ITO ATSUKO TAKANO YASUO KUBOTA JIRO MATSUMOTO MASAKO MIZOGUCHI 《Pigment cell & melanoma research》1998,11(5):291-298
Stem cell factor (SCF) has been suggested to be indispensable for the development of neural crest cells into melanocytes because Steel mutant mice (i.e., Sl/Sf1) have no pig-mented hairs. On the other hand, it has been demonstrated that the addition of endothelin 3 (ET-3) or TPA to neural crest cell cultures can induce melanocyte differentiation without addition of extrinsic SCF. In this study, we excluded the influence of intrinsic SCF by using SI/SI mouse embryos to study more precisely the effects of natural cytokines, such as extrinsic soluble SCF or ET-3, or chemical reagents, such as TPA or cholera toxin. We found that SCF is supplied within the wild-type neural crest explants and that ET-3 cannot induce melanocyte differentiation or proliferation without SCF. These results indicate that SCF plays a critical role in survival or G1/S entry of melanocyte progenitors and that SCF initially stimulates their proliferation and then ET-3 accelerates their proliferation and differentiation. TPA has the ability to elicit neural crest cell differentiation into melanocytes without exogenously added SCF but it is not as effective as SCF because many more melanocytes developed in the wild-type neural crest explants cultured with TPA. 相似文献
153.
MARIA GABRIELA CUEZZO 《Zoological Journal of the Linnean Society》2003,138(4):449-476
The monophyly of the land snail family Camaenidae has been in doubt due to a disjunct bihemispheric distributional pattern and to the lack of morphological synapomorphies. A cladistic analysis is presented using an ingroup composed of representatives of the three subfamilies distributed in Australia and 52 other species with American distribution. Bradybaenidae, Helicidae and Helminthoglyptidae were used as outgroups. Fifty morphological characters were treated as unordered and analysed using Pee-Wee ver. 2.9, a program for parsimony analysis using implied weights. The results of the analysis support Camaenidae as a monophyletic family (synapomorphies: oval genital orifice, absence of penial sheath). Two of the three Australasian subfamilies, Sinumeloninae and Camaeninae, are monophyletic in the strict consensus tree. The American taxa are classified in eight genera and arranged into two main clades. Caracolus is proposed as the sister group of the American Continental Camaenidae. The genus Solaropsis , previously excluded from this family by different authors, is reassigned to Camaenidae. Shell characters proved to be phylogenetically informative in defining Pleurodonte , Caracolus , Solaropsis , Isomeria and Labyrinthus . © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society, 2003, 138, 449–476. 相似文献
154.
SORAYA C M LEAL-BERTIOLI ALETÉIA V PASCOAL PATRÍCIA M GUIMARÃES MARIA F GROSSI DE SÁ REJANE L GUIMARÃES DAMARES C MONTE DAVID J BERTIOLI 《The Annals of applied biology》2003,143(3):349-357
The protein Tarin 1, from Colocasia esculenta, was expressed in Nicotiana tabacum. Bioassays were done on plants expressing Tarin 1 at different levels using Spodoptera frugiperda larvae, various bacteria and fungi and the root‐knot nematode Meloidogyne javanica. It was found that S. frugiperda larvae fed on transformed plants had retarded and lower pupation, lower accumulated biomass and higher mortality rate than larvae fed on control plants. Also, Tarin 1 was found to inhibit the growth in vitro of Pseudomonas syringae pv. tomato. For Meloidogyne javanica, both relative replication and root damage were greater in control plants than in transformed plants, but the results were not statistically significant. This work illustrates the effects of plants expressing Tarin 1, on the growth and development of insects and bacteria, and shows its potential for pest management. 相似文献
155.
Scanning and Transmission Electron Microscopic Observations on Surface Structures of Three Turbellarian Species 总被引:1,自引:0,他引:1
MARIA REUTER 《Zoologica scripta》1978,7(1-4):5-11
The body surface of Microstomum lineare, Bothriomolus balticus and Archilopsis unipunctata was examined in scanning electron microscope. The threedimensional appearance of adhesive duo-gland organs, receptor cilia, globular bodies and pistil-like projections is described. The adhesive duo-gland papillae of Bothriomolus and Archilopsis appear as bouquetlike structures on either side of the tail as well as on the cilia covered body. In Microstomum the papillae occur as single projections among the ciliary body für. Supplementary TEM investigation revealed crystalline bodies in the cytoplasm of viscid gland cells. 相似文献
156.
157.
The desert woodrat complex (Neotoma lepida group) is a set of four closely related species occupying the arid lands of western North America. We have developed 18 polymorphic microsatellite loci to analyse the population structure, mating patterns, and hybridization at points of contact between the contiguously allopatric species in the complex. 相似文献
158.
LISA M. SCHLOEGEL LUÍS FELIPE TOLEDO JOYCE E. LONGCORE SASHA E. GREENSPAN CONRADO AUGUSTO VIEIRA MARIA LEE SERENA ZHAO CATHERINE WANGEN CLAUDIA MARIS FERREIRA MÁRCIO HIPOLITO ANGELA J. DAVIES CHRISTINA A. CUOMO PETER DASZAK TIMOTHY Y. JAMES 《Molecular ecology》2012,21(21):5162-5177
Global amphibian declines are linked with the presence of specific, highly virulent genotypes of the emerging fungal disease chytridiomycosis caused by Batrachochytrium dendrobatidis (Bd) known as the global panzootic lineage (Bd‐GPL). The global trade in amphibians for human consumption is suspected to have facilitated emergence of the disease, but evidence to support this is largely lacking. Here, we investigated the role the Lithobates catesbeianus (North American bullfrog) trade in spreading Bd genotypes by comparing strains associated with L. catesbeianus to a global panel using 36 sequenced loci from multiple chromosomal regions. Most bullfrogs were infected with Bd‐GPL genotypes, but we also detected novel, highly divergent Bd genotypes (Bd‐Brazil) from a live bullfrog in a US market and from native Brazilian anurans in the Atlantic Forest where bullfrogs are widely farmed. Sexual reproduction was also detected for the first time in Bd in the form of a hybrid genotype between the Bd‐GPL and Bd‐Brazil lineages in the Atlantic Forest. Despite the demonstration that ribosomal RNA types in Bd fail to undergo concerted evolution (over 20 sequence types may be found in a single strain), the Bd‐GPL and Bd‐Brazil lineages form largely separate clusters of related internal transcribed spacer (ITS) RNA sequences. Using ITS sequences, we then demonstrate the presence of Bd‐Brazil in Japan, primarily on invasive L. catesbeianus. The finding that Bd is capable of sexual reproduction between panzootic and endemic genotypes emphasizes the risk of international wildlife trade as a source of additional Bd epizootics owing to hybridization. 相似文献
159.
MILENA BARCELOS CARDOSO MARIA TERESA SCHIFINO-WITTMANN MARIA HELENA BODANESE-ZANETTINI 《Botanical journal of the Linnean Society. Linnean Society of London》2000,134(4):549-556
Chromosome numbers were determined in 52 individuals of 14 taxa of Leucaena Benth. from 22 populations. For L. cuspidata and L. kmpirana these are the first published chromosome counts. Intraspecific variability was found for L. lempirana, L. macrophjlta and L. shanonii , and one diploid population of the tetraploid species L. pallida was identified. Comparison of our data with those in the literature showed that for L. collinsii and L. macrophylla there is a relationship between chromosome number and subspecies delimitation. The variability detected in chromosome numbers shows the complexity of the diploid and tetraploid species evolution, and suggests multiple origins for some of the polyploid taxa. 相似文献
160.
MARIA DOLORES LLEDÓ MANUEL B. CRESPO ANTHONY V. COX MICHAEL F. FAY MARK W. CHASE 《Botanical journal of the Linnean Society. Linnean Society of London》2000,132(2):175-191
Phylogenetic relationships of Limoniastrum and other genera of subfamily Staticoideae (Plumb-aginaceae) were studied using parsimony analysis of the plastid gene rbc L, the intron of trn L and the intergene spacer of trnL-trn F. Our analysis showed that Limoniastrum was polyphyletic. Limoniastrum ifniense , in both rbc L and combined data analyses, is sister to Armeria and Psylliostachys , whereas in the trn L-F (intron and spacer combined) analysis it is sister to a clade composed of Acantholimon, Dictyolimon and the remaining species of Limoniastrum . In all analyses, the five remaining species of Limoniastrum (excluding Limoniatrum ifniense ) formed a clade with two groups of species: L. monopetalum+L. guyonianum and those sometimes considered as the segregate genus Bubania ( L.feei, L. weygandiorum and L. rechingeri ). Levels of sequence divergence among these three groups of Limoniatrum were greater than for other well supported genera in the family and, in combination with morphological differences and paucity of synapomorphies, led us to conclude that separate generic status for each of the three clades is warranted. 相似文献