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1.
Long distance vocalizations have been shown to be good indicators of genetic species in primates. Here the loud calls of two recently identified greater galago taxa —Galago crassicaudatus andG. garnettii — are compared and analyzed statistically. Observed differences in call structures are investigated further as potential indicators of differences in the structures of habitats frequented by the two species. Although the calls share a repetitive structure, and show similar dominant frequency bands (1,000 – 1,500 Hz), they differ significantly in the number of units per call, unit duration, inter-unit interval, highest frequency, lowest frequency, dominant frequency band, first harmonic, and call duration. The duration of theG. crassicaudatus call is more than twice that ofG. garnettii. Strong intraspecific consistency is seen in the most energetic frequency bands (dominant frequency band and first harmonic), and durations of the individual units and inter-unit intervals. Information important to species recognition is thus most likely to be contained in these features. Individual recognition may be encoded in the relative emphasis of higher level harmonics. The frequency structures of the calls will reflect requirements for acoustical transmission in a forest environment, as well as structural constraints imposed by body size. Higher frequencies detected in theG. garnettii call (up to 8,500 Hz) may have a functional significance related to distance estimation, or may simply be a reflection of smaller body size. The greater modulation of theG. garnettii call suggests that its habitat constitutes a denser or more turbulent medium for sound transmission than does the habitat ofG. crassicaudatus.  相似文献   

2.
Two sympatric species of galago,Galago zanzibaricus andG. garnettii, differed significantly in diet (judged mainly by fecal analysis) and substrate use at each of two coastal forest sites in Kenya. The larger-bodiedG. garnettii tended to use branches of a bigger diameter and to be found higher in the canopy than the smallerG. zanzibaricus. The latter species spent most of its time in the thick undergrowth. The larger species ate more fruit than the smaller. There were differences between the species in the type of invertebrate prey remains found in the feces. It is suggested that the differences in habitat use were influenced by the different body sizes of the two galagos, which so enabled these closely related species to coexist. Order of authorship is alphabetical.  相似文献   

3.
The biflagellate zoospores ofProtoderma sarcinoidea and the quadriflagellate zoospores ofChamaetrichon capsulatum are each covered by an amorphous, mucous material and a single layer of square scales, and the pyrenoid matrix is traversed by one or more thylakoid membranes. In the flagellar apparatus the basal bodies ofP. sarcinoidea and the upper basal bodies ofC. capsulatum are displaced in the counterclockwise absolute orientation, while the lower basal bodies ofC. capsulatum are directly opposed. Other components of the flagellar apparatus observed in each alga include: cruciately arranged d and s rootlets, each associated with an electron-dense component; simple terminal caps comprised of large and small subunits; a terminal electron-dense mass located near the proximal end of each basal body inP. sarcinoidea and near the upper basal bodies inC. capsulatum; and two rhizoplasts. Components specific to one or the other species include a single accessory basal body inP. sarcinoidea and a fibrous, electron-opaque band that links the upper and the lower basal bodies inC. capsulatum. The flagellar apparatus architecture ofP. sarcinoidea resemblesGayralia oxysperma, while that ofC. capsulatum is similar toTrichosarcina polymorphum andUlothrix species, all of which are included in theUlothrix-group,Ulotrichales, Ulvophyceae.  相似文献   

4.
Summary The DNA's ofMicrococcus lysodeikticus andClostridium perfringens were fragmented to about 7 000 nucleotide pairs long by shear and fractionated with respect to buoyant density of mercury complexes in Cs2SO4. The distribution of G + C content in both DNA's was characteristically asymmetric. InM. lysodeikticus DNA, low G + C fragments were more numerous than high G + C fragments, whereas inC. perfringens DNA, high G + C fragments were more numerous than low G + C fragments. The G + C content of fragments ofM. lysodeikticus DNA varied from 70 to 77%, with a mean and standard deviation of 73.7 ± 1.92% G + C and that ofC. perfringens DNA varied from 27 to 34%, with a mean and standard deviation of 29.8 ± 1.34% G + C. The standard deviation was smaller than that ofEscherichia coli DNA fragments of similar size. Biological meanings of relatively low heterogeneity in nucleotide composition inM. lysodeikticus andC. perfringens are discussed.  相似文献   

5.
Molecular divergence betweenGossypium klotzschianum andG. davidsonii was studied. The former is endemic to five of the larger islands of the Galapagos, whileG. davidsonii is restricted to the southern half of Baja California, approximately 2 500 km distant. A substantial body of genetic and taxonomic data suggests that these two species are related as progenitor and derivative. Interspecific hybrids are fully fertile, with no evidence of F2 breakdown and normal segregation of genetic markers. Allozyme analysis of 33 populations for 41 loci indicated that the allelic composition ofG. klotzschianum represents a subset ofG. davidsonii. Although genetic diversity is relatively restricted in both species, calculated measures demonstrate higher levels of genetic variability and greater population structuring inG. davidsonii than inG. klotzschianum. The interspecific genetic identity of 0.87 is typical for progenitor-derivative species pairs. Chloroplast DNAs were surveyed for variation with 25 restriction enzymes using hybridization probes that cover the entire chloroplast genome. No intraspecific and little interspecific variation was detected among 560 cpDNA restriction sites, representing sequence information for approximately 3200 nucleotides. Only 3 mutational differences distinguished the two species, resulting in a sequence divergence estimate of 0.09%. Divergence times were estimated from both the isozyme data and the cpDNA restriction site data. Although these estimates have several sources of error, both molecular data sets were congruent in suggesting that the two lineages diverged between 250000 and 700000 years ago. Accumulated evidence suggests that dispersal was from Baja California to the Galapagos Islands rather than the reverse, and most likely was mediated by trans-oceanic drift.G. klotzschianum may be the only species of the endemic Galapagos flora to have arisen from a northern Mexican progenitor.  相似文献   

6.
Reproductive parameters were compared between two subspecies of the lesser bushbaby, Galago senegalensis braccatusand G. s. moholi.Adult body weights for both male and female G. s. braccatuswere significantly higher than adult body weights of G. s. moholi,as were infant birth weights. The mean gestation length of G. s. braccatuswas significantly longer than that of G. s. moholi. G. s. moholihad a higher incidence of twinning than G. s. braccatus.Puberty in females occurred significantly later in G. s. braccatusthan in G. s. moholi.These differences are of such magnitude that hybridization of G. s. braccatuswith G. s. moholiwould be unlikely. These differences, if augmented by additional evidence, may warrant distinction of the two subspecies at the species level.  相似文献   

7.
8.
Ganoderma lucidum is a well-known and important medicinal mushroom, but its genetic modification has not been reported. We developed an efficient procedure for isolation and regeneration of protoplasts fromG. lucidum. To construct a vector for high-level expression of heterologous genes inG. lucidum, the 1.4-kb regulatory region of the glyceraldehyde-3-phosphate dehydrogenase gene (GPD) was isolated from the genomic DNA ofLentinus edodes, and theGPD promoter was fused to the β-glucuronidase (GUS) and bialaphos resistance (bar) genes. Using the resulting construct, p301-bG1, an efficient transformation system based on electroporation was established forG. lucidum. GUS expression was observed among transformants conferring bialaphos resistance, indicating that theL. edodes GPD promoter can be used for expression of exogenous genes inG. lucidum. We also studied green fluorescent protein (GFP) as another reporter for transformation ofG. lucidum. TheL. edodes GPD promoter was fused respectively to theGFP andbar genes, and the resulting construct, p301-bg, was introduced intoG. lucidum. StableGFP expression in transformants was detectable by fluorescence microscopy, suggesting the suitability ofGFP as a reporter system in transformation of this mushroom. This is the first report of an efficient transformation system forG. lucidum using different reporters, paving the way for genetic modification of this famous medicinal mushroom.  相似文献   

9.
The feeding behavior and diet of two species of bushbaby, Galago senegalensisand Galago crassicaudatus,in South Africa were examined in relation to seasonal changes in climate. The populations studied were allopatric, but both fed predominantly on Acaciagum and invertebrates. Data on their diet were collected by direct observation of a radiocollared female of each species and by analysis of fecal samples. Differences in diet were found between the species within seasons and within species between the seasons. Both spent more time gum-feeding in winter than in summer. Prey size and type differed between the species in summer but converged in winter. The quantity of insects taken was fairly similar between seasons for G. senegalensisbut dropped considerably for G. crassicaudatusin winter. These observations are interpreted in terms of interspecific differences in feeding strategies, which are considered to be a function of the difference in body size of the two galago species.  相似文献   

10.
Three new species belonging toMarasmius sectionSicci (Agaricales) are described and illustrated from eastern Honshu, Japan:Marasmius nocturnus sp. nov., forming a dark brown pileus and marginate lamellae, was found on leaf litter inPasania—Quercus forests;Marasmius occultatus sp. nov., producing brownish orange or light brown basidiomata and long, cylindrical-fusoid basidiospores, was found on dead fallen twigs ofAphananthe aspera andQuercus myrsinaefolia;Marasmius opulentus sp. nov., having a reddish orange pileus and a pubescent stipe, was found on leaf litter in laurel-leaved forest.  相似文献   

11.
The capitular and floral morphology and anatomy ofBidens L. andCoreopsis L. were studied. All the North American species ofCoreopsis were studied. Selected species ofBidens from North and South America andCoreopsis from South America were included. The results were compared with previous observations on African species ofBidens (incl.Coreopsis). Emphasis was given to character states of the ray florets, paleae, stylearm apices, outer phyllaries, achenes, and pollen grains. Some of the character states are unique features ofCoreopsis, e.g., globular and elongately conical receptacles, deltoid outer phyllaries, truncate and indistinctly 3–5-dentate, 3–4-lobed ray florets, narrowly spathulate paleae, subulate paleae with linear-filiform upper half, hairy and apically 3-cleft paleae, truncate, convex or shallowly conical stylearm apices with the sweeping hairs limited to the area above the stigmatic surfaces and the orbicular to circular achenes. The cylindric setaceous pappus bristles so commonly encountered inBidens are unknown inCoreopsis. The pappus bristles inCoreopsis are paleaceous but similar, though thicker ones are also found in African species ofBidens (incl.Coreopsis) with winged achenes. Twin-celled hairs (setulae) with differing degrees of wall thickness are found on the achenes ofCoreopsis sect.Pseudoagarista (Mexico and South America),Coreopsis sect.Pugiopappus (California), AfricanBidens with winged achenes (e.g.,B. prestinaria, B. macroptera) and some North AmericanBidens (e.g.,B. aristosa). Similar sclerotic parenchyma make up the achenial wings of species in both genera. These may be interpreted as homologous structures, indicating the underlying similarity of these taxa and their derivation from a common ancestral stock.  相似文献   

12.
The nucleotide sequences of ten SP11 and nine SRK alleles in Raphanus sativus were determined, and deduced amino acid sequences were compared with those of Brassica SP11 and SRK. The amino acid sequence identity of class-I SP11s in R. sativus was about 30% on average, the highest being 52.2%, while that of the S domain of class-I SRK was 77.0% on average and ranged from 70.8% to 83.9%. These values were comparable to those of SP11 and SRK in Brassica oleracea and B. rapa. SP11 of R. sativus S-21 was found to be highly similar to SP11 of B. rapa S-9 (89.5% amino acid identity), and SRK of R. sativus S-21 was similar to SRK of B. rapa S-9 (91.0%). SP11 and SRK of R. sativus S-19 were also similar to SP11 and SRK of B. oleracea S-20, respectively. These similarities of both SP11 and SRK alleles between R. sativus and Brassica suggest that these S haplotype pairs originated from the same ancestral S haplotypes.  相似文献   

13.
A preliminary account of Entolomataceae from Costa Rica is presented. Three new taxa are described, two inClitopilus, one inRhodocybe, and three new combinations are proposed inInocephalus. Five taxa ofClitopilus are reported for the first time from Costa Rica and a key to species is provided. Four species ofRhodocybe are discussed and a key to the six species known from Costa Rica is also provided.Alboleptonia earlei, Inocephalus murraii, Inocephalus quadratum, Rhodocybe incarnata andRhodocybe pseudonitellina are now known to occur in Costa Rica.  相似文献   

14.
Melaleuca alternifolia andM. linariifolia are commercially important Australian species harvested for their essential oils. Both species have relatively narrow and disjunct distributions on the central coast of eastern Australia. Variation in the chloroplast genome was assessed for eight individuals from each of twelve populations, representing the species' geographic range. Low nucleotide diversity withinM. alternifolia contrasted with high nucleotide diversity inM. linariifolia. CpDNA data are consistent with the southern population ofM. alternifolia being a hybrid population withM. linariifolia. The two species are sympatric in this region. Variation inM. linariifolia was geographically structured, with northern populations differing from southern populations by seven restriction site mutations, five length mutations and an inversion. There was no evidence of hybridisation of the cp genome of northernM. linariifolia with the partially sympatric speciesM. trichostachya. Intra- and interspecific variation in the chloroplast genomes ofM. alternifolia, M. linariifolia, andM. trichostachya indicate considerable potential for the use of intraspecific cpDNA studies in examining phylogenetic relationships in melaleucas.  相似文献   

15.
From recent isolates of microfungi on soil materials collected at several localities in the world, five new taxa of the Onygenales are described and illustrated. A new monotypic genus,Kraurogymnocarpa lenticulospora, is proposed. New species are described inAmauroascus, Aphanoascus, andArachnomyces. A new variety ofPseudogymnoascus roseus is also proposed.  相似文献   

16.
Mating type (MAT)-specific fragments of the two idiomorphs ofGibberella fujikuroi (anamorph,Fusarium moniliforme) were obtained by PCR amplification using primers to conserved regions ofMAT homologs from other fungal species and used to assign mating type by molecular criteria rather than the arbitrary historical designation. Mating type—strains of mating populations A-E and a mating type+strain of mating population F carry an α-box motif and should therefore be designatedMAT-1. Mating type+strains of mating populations A-E and a mating type—strain of mating population F carry an HMG-box motif and should be designatedMAT-2. Thus, assessment of mating type ofG. fujikurol strains can be easily achieved usingMAT-specific primers.  相似文献   

17.
Cellulomonas cartalyticum was found to contain a peptidoglycan type different from that of the other species ofCellulomonas. The diamino acid is lysine instead of ornithine and the interpeptide bridge consists ofd-Asp-d-Ser. The same peptidoglycan type occurs inCorynebacterium manihot, Brevibacterium liticum andArthrobacter luteus. These non cellulolytic organisms are most likely not closely related withCellulomonas cartalyticum, as indicated by the very different G+C content of their DNA, although they formed a narrow cluster includingC. cartalyticum when numeric taxonomical methods were applied.
  相似文献   

18.
Two species ofDerbesia (Class Chlorophyceae),D. marina andD. tenuissima, have been studied for the purpose of obtaining a better understanding of their morphological details and life histories, using preserved and living specimens as well as laboratory cultures. The life histories of both species were completed in the laboratory, starting from both zoospores and zygotes. Specimens were collected at Asamushi, Aomori-ken, and Shimoda, Shizuoka-ken. Their life history types are fundamentally identical, zoospores giving rise upon germination toa Halicystis-phase, while zygotes grow into aDerbesia-phase. The thallus of theHalicystis-phase which alternates withD. marina is the same as that ofH. ovalis which grows in the northern regions of Japan. On the other hand, the thallus of theHalicystis-phase alternating withD. tenuissima is the same as that ofH. parvula known to occur in the temperate to subtropical regions of Japan. These results coincide with those obtained withD. marina andD. tenuissima in Europe, where the type localities of both species are located. Specimens assignable to these two species were collected at several localities in Japan and, as a result of detailed examination of the morphology, they are believed to be identical with eitherD. marina orD. tenuissima.  相似文献   

19.
Intergeneric crosses were made between representatives of the genomically-defined generaElymus, Agropyron, Elytrigia, Pseudoroegneria, andThinopyrum. The genomic constitution ofElytrigia repens, the type species ofElytrigia, is shown to be SSH, a genomic combination otherwise found only inElymus. The S genome ofPseudoroegneria has almost always a dominant influence on the morphology of the taxa of which it is a component.Wang (1989) showed that the J genome inThinopyrum and the S genome have considerable homoeology, with a mean c-value of 0.35 in diploid SJ hybrids. A genetic coherence from S to SJe, Je, JeJb, and Jb can be expected, agreeing with the continuous morphologic variation pattern observed. Because of the absence of morphological discontinuities between the taxa,Pseudoroegneria (S),Elymus (SH, SY, sometimes with additional genomes),Elytrigia (SSH, SSHX), andThinopyrum (SJ, SJJ, J) are best treated as a single genus,Elymus, following the generic concept ofMelderis in Flora Europaea and Flora of Turkey. The basic genomic constituents ofElymus will then be the S and/or J genomes.Agropyron, with diploids, tetraploids, and hexaploids based on the P genome is morphologically distinct from other genera inTriticeae. In a few species ofElymus andPseudoroegneria, a P genome is an additional constituent. In these cases the P genome has a negligible morphological influence. Therefore, it seems reasonable to maintainAgropyron as a separate genus.  相似文献   

20.
Basic chromosome number inGalaxia is believed to be x = 9, and this number, or multiples, occurs in all species of subgenusGalaxia. In subgenusEurystigma, G. barnardii has n = 8,G. versicolor n = 8 and 7,G. citrina n = 8, 7 and 17 whileG. variabilis has n = 7 exclusively. Karyotypes in forms ofG. versicolor with n = 7 and inG. variabilis are quite different and clearly originated independently. Karyotypic features provide evidence for the hypothesis that changes in chromosome number were accomplished through chromosome fusion either by classical Robertsonian translocation, or unequal reciprocal translocation.  相似文献   

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