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71.
S. ROQUES J. A. GALARZA E. MACPHERSON G. F. TURNER C. RICO 《Molecular ecology resources》2007,7(4):661-663
We have developed nine new microsatellite markers for the two‐banded sea bream (Diplodus vulgaris) from an enriched genome library protocol. All these loci are polymorphic, with mean allelic diversity of 13 (range 5 –21), and expected and observed heterozygosities from 0.641 to 0.932 and 0.428 to 0.914, respectively. Cross‐species tests in two close‐related species of the genus Diplodus (D. sargus and O. melanura) revealed successful amplifications at 8 out of 9 loci, with mean allele number of 4.75 (range 2–8) and 5.50 (range 3 –10), respectively. These results are consistent with the close phylogenetic relationships between the three species, indicating this set of primers might prove useful for studying the levels of genetic diversity and population differentiation in these three species and in other phylogenetically close species of the genus Diplodus and Sparus. 相似文献
72.
Xylopine, an aporphine alkaloid contained in the bark of Xylopiadiscreta strongly inhibits growth of Scenedesmus obliquus; 50%inhibition was caused by 2x105 M of xylopine. Photosynthesis was also strongly inhibited by xylopine at concentrationsabove 104 M. Effects on photosynthesis, however, differeddepending on the ratio of alkaloid concentration to cell concentrationin the reaction mixture, so that under certain experimentalconditions with concentrations of xylopine below 104M, there was some acceleration of photosynthesis. Xylopine strongly inhibited the HILL reaction with benzoquinoneas the HILL oxidant. Respiration was not affected at concentrationscompletely inhibiting photosynthesisd growth of the alga. A probable role of the aporphine alkaloid in controlling lichengrowth in nature is discussed. (Received March 25, 1970; ) 相似文献
73.
The purpose of this study was to test for correlations of mass-independent nonshivering thermogenesis (NST) in rodent species with climatic factors such as maximum and minimum geographic temperature. We first analyzed whether the responses of rodents show a phylogenetic signal. If so, and if the NST over a broad geographical range is similar, then such responses probably reflect physiological evolutionary adaptation. Our results show that NST did not show phylogenetic signal, appears to be evolutionary labile and is negatively correlated with environmental temperature. We predicted that species evolved in cold climates will exhibit higher mass-independent NST than species from warmer habitats. Indeed, we observed that the relationships between mass-independent NST and minimum temperature ( r s =−0.411, P =0.009) as well as between NST and maximum temperature ( r s =−0.443, P =0.004) were both negatively and significantly correlated, thus supporting our predictions. Thus, thermal physiology may be a significant factor underlying the ecological and evolutionary success of animals. Finally we suggest that due to the pressing need to explain and predict the likely biological impact of climatic change, advances in this field are necessary. 相似文献
74.
SANTIAGO ANDRÉS‐SÁNCHEZ ENRIQUE RICO ALBERTO HERRERO MARÍA SANTOS‐VICENTE M. MONTSERRAT MARTÍNEZ‐ORTEGA 《Botanical journal of the Linnean Society. Linnean Society of London》2009,159(1):68-87
The aim of this study was to quantify the phenotypic differences amongst the taxa included in Veronica subgenus Pentasepalae, represented in the western Mediterranean area. In combination with previously obtained data on genotypic differences, this enabled the recognition of eight taxonomic units. The delimitation of the boundaries among species and subspecies was mainly based on molecular data, whereas the best characters to discriminate taxa were selected after an accurate study of herbarium material and living populations. Such a selection was also supported by a detailed morphometric study of 30 quantitative leaf traits in 88 populations. Several morphological characters, including the length of the trichomes, length of the petiole and leaf division, were found to be robust, and could be useful in the identification of the taxa involved. As a conclusion, a key to the taxa is proposed, as well as a complete nomenclatural treatment for the group, which includes the typification of several names. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 68–87. 相似文献
75.
GRACIELA GARCÍA GABRIELA WLASIUK ENRIQUE P. LESSA 《Zoological Journal of the Linnean Society》2000,129(1):93-110
Phylogenetic relationships based on 324 base pairs of the mitochondrial cytochrome b gene were examined in 14 species of the genus Cynolebias. The monophyly of the genus relative to three outgroup taxa belonging to the family Rivulidae was supported by the sequence data. Bootstrap values corroborated the existence of intrageneric monophyletic units in both parsimony and Neighbour-joining analyses. These include a Cynolebias bellottii-C. wolterstorffl clade, a C. adloJfi-2, C. duraznensis, C. viarius and C adloffi-1 group, and a C. gymnoventris, C. luteoflammulatus pair and the strongly supported assemblage that includes C. prognalhus and C. cheradophilus clade. Phylogenetic relationships remain poorly supported for C. nigripinnis, C. qffinis and C. alexandri, and unresolved among the previous ingroup clades. Cytochrome b sequences reveal an unexpectedly high level of divergence among species of the genus Cynolebias. Consequently, cytochrome b shows good resolution of recent cladogenetic events but limited phylogenetic information at deeper nodes. High levels of sequence divergence span a broad range within Cynolebias. The highest sequence divergence (c. 28%) occurred among C. antenori and the remaining species of the genus. The minimum divergence value (4.5%) is exhibited by sympatric species C. cheradophilus and C. prognathus. 相似文献
76.
JORGE ENRIQUE MORENO PATIÑO DAVID W. ROUBIK WILLIAM T. WCISLO 《Ecological Entomology》2012,37(4):309-317
1. Spatial and temporal availability of pollen helps shape bee foraging behaviour and productivity, which has been studied in great detail at the landscape level, but never in a diverse tropical forest. 2. To study the effect of spatio‐temporal variation in resource distribution on pollen use and productivity, we identified pollen from spatially explicit nest collections of two generalist sweat bees, Megalopta genalis Meade‐Waldo and M. centralis Friese, from Barro Colorado Island, Panama, a 50‐ha forest dynamics plot during the 2007 dry and early wet seasons. Pollen from nests collected in 1998–1999 without spatial information was also identified. 3. Bees used pollen of at least 64 species; many of these occurred in only one collection. The 2007 collections contained pollen of 35 different species, but were dominated by five species, especially Hura crepitans L. and Pseudobombax septenatum (Jacq.) Dugand. 4. Temporal availability, but not distance from nest, influenced flower use at a 50‐ha scale. 5. Body size was not associated with minimum flight distance as inferred from pollen collections. 6. Nest productivity and pollen diversity decreased from the dry to wet seasons, mirroring community‐level availability of floral resources. 7. Results suggest that on a scale of 50 ha, bees are choosing certain host plant species regardless of distance from the nest, but adjusting foraging behaviour opportunistically based on the temporal availability of host flowers. 相似文献
77.
ENRIQUE MACPHERSON 《Zoologica scripta》1988,17(1):69-75
Three new species of the lithodid genus Paralomis from the Sulawesi (Celebes) Islands, P. ochthodes sp.n., Chilean coast, P. tuberipes sp.n., and Antarctic Ocean, P. birsteini sp.n., are described and illustrated. The first two species have features that set them well apart from other species of the genus. Characters are also given to distinguish P. birsteini from the closely allied P. spectabilis Hansen (North Atlantic). 相似文献
78.
DAVID HARPER ENRIQUE VILLAS GLADYS ORTEGA 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2004,37(3):271-279
The dalmanellidine brachiopods formed a diverse, abundant and long-lived group of Palaeozoic benthos, reaching their acme during the later Ordovician. The oldest members of the suborder occur in Arenig rocks, where both superfamilies, the Enteletoidea and Dalmanelloidea, are represented by relatively simple morphotypes. The reidentification of Lipanorthis Benedetto from the Tremadocian rocks of Argentina as a linoporellid significantly extends the record of the dalmanellidines into older strata. The relatively complex morphology of the recently described taxon and its marked morphological divergence from other Arenig dalmanellidine taxa suggest a significant pre-Ordovician record for the punctate orthide brachiopods. 相似文献
79.
ENRIQUE FONT GUILLEM PÉREZ I DE LANUZA CARLOS SAMPEDRO 《Biological journal of the Linnean Society. Linnean Society of London》2009,97(4):766-780
Ultraviolet (UV) colorations have garnered extensive theoretical and empirical treatment in recent years, although the majority of studies have concerned themselves with avian taxa. However, many lizards have acute visual systems with retinal photoreceptors that are sensitive to UV wavelengths, and also display UV-reflecting colour patches. In the present study, we used UV photography and full-spectrum reflectance spectrophotometry to describe intra- and intersexual colour variation in adult ocellated lizards Lacerta ( Timon ) lepida and to obtain evidence of UV-based ornamentation. We also investigated whether any colour traits correlate with morphological traits potentially related to individual quality. The results obtained show that the prominent eyespots and blue outer ventral scales (OVS) that ocellated lizards have on their flanks reflect strongly in the UV range and are best described as UV/blue in coloration. The eyespots of males are larger and cover a larger surface area than those of females. However, these differences can be entirely accounted for by sex differences in body size, with males being generally larger than females. We also found differences in the shape of reflectance curves from males and females, with the eyespots and blue OVS of males being more UV-shifted than those of females. Other body regions have extremely low UV reflectance and are not sexually dichromatic. Eyespot size and the total surface area covered by eyespots increases with body size in males but not in females, suggesting that they may be signalling an intrinsic individual characteristic such as body size or male fighting ability. We also discuss the alternative and non-exclusive hypothesis that eyespots may function in lizards of both sexes as protective markings against predators. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 766–780. 相似文献
80.
SANTIAGO CASTROVIEJO F.L.S. ENRIQUE VALDÉS-BERMEJO 《Botanical journal of the Linnean Society. Linnean Society of London》1990,104(4):303-308
On the basis of the study of the original material used by Planchon, the typification previously made by other authors is discussed, and an interpretation of the U. minor-galli group is presented. We conclude that the name U. galli must continue in use in its traditional sense, and, therefore, U. cantabricus Alvarez Martínez el al. must become a mere synonym. The new combinations U. breoganii (Castroviejo & Valdés-Bermejo) Castroviejo & Valdés-Bermejo, stat. nov. and U. minor subsp. gallii (Planchon) Castroviejo & Valdés-Bermejo, comb. nov. are proposed. 相似文献