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1.
Mixed species groups and hybridization are common among primates, yet these phenomena are rare and poorly understood for the
genus Alouatta. In this study, we describe the composition of howler groups in a sympatric area of Alouatta caraya and Alouatta clamitans and provide new evidence for the occurrence of interspecific hybridization. Between October 2006 and April 2007, 11 howler
groups were located in a 150-ha forest fragment: two monospecific groups of A. caraya, two monospecific groups of A. clamitans, two groups composed of A. clamitans and hybrid morphotypes (A. caraya × A. clamitans), and five groups composed of both species together with hybrid morphotypes (mixed species groups). The average size of the
studied groups was 5.2 ± 1.2 individuals. Monospecific and mixed groups (mixed species groups + groups with hybrids) did not
differ significantly in their sizes. In total, the sex/age ratios were 1 AM:1.5 AF:0.2 SAM:0.5 JUV:0.2 INF and the species
ratios were 1 A. caraya:1.6 A. clamitans:0.4 A. caraya × A. clamitans. The ratio of immatures to 1AF was larger in the monospecific groups (0.75 immatures:1AF) than in mixed groups (0.29 immatures:1AF),
possibly reflecting a lower viability in the latter. Two features of the hybrid morphotypes of the upper Paraná River support
their status as true hybrids: the polymorphism of their coloration patterns and the extremely female-biased sex ratio. The
effects of Haldane’s rule and population fragmentation on the interactions between both species are discussed.
Contribution number 1689 of the Departamento de Zoologia, Universidade Federal do Paraná (UFPR), Caixa Postal 19020, 81531-990,
Curitiba, Paraná, Brazil. Contract grant sponsor: Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). 相似文献
2.
Aguiar LM Mellek DM Abreu KC Boscarato TG Bernardi IP Miranda JM Passos FC 《Primates; journal of primatology》2007,48(3):245-248
Records of sympatry between Alouatta caraya and A. clamitans are rare despite their extensive range overlap. An example of their current sympatry and the rediscovery of free-ranging
potential hybrids of A. caraya and A. clamitans in the forests of the Upper Paraná River, Southern Brazil, are reported in this paper. Eight groups were observed in the
study area: five monospecific groups of A. caraya, two of A. clamitans, and a group containing two adult males and two adult females of A. caraya and a sub-adult male and two adult females identified as Alouatta sp. The color of the last three individuals was a mosaic between the two species; this is consistent with previously described
variations in museum specimens collected in the Paraná River in the 1940s that had been identified as potential hybrids. The
results from this study emphasize the need for scientific studies in the region of the Ilha Grande National Park, one of the
few regions in the Paraná River that currently harbors both howler species.
Contribution number 1637 of the Departamento de Zoologia, Universidade Federal do Paraná, Caixa Postal 19020, 81531-980, Curitiba,
Paraná, Brasil. 相似文献
3.
Wang Minqin Zhao Junsheng Peng Zhenying Guo Wei Wang Yun Wang Le Xia Guangmin 《Plant Cell, Tissue and Organ Culture》2008,92(2):121-130
In order to investigate chromosome elimination in symmetric somatic hybridization between Bupleurum scorzonerifolium and Arabidopsis thaliana, protoplasts were isolated from suspension cultures of both A. thaliana and B. scorzonerifolium parents. Biparental protoplasts were mixed at a rate of 1.5:1 and fused with PEG-method. After protoplast fusion, the products
were cultured in the P5 liquid medium for microcallus formation. Single cell lines formed from microcalli after subculturing
on the MB1 (Xia and Chen, Plant Sci 120:197–203, 1996) solid medium. The putative somatic hybrid cell lines were identified
by cytological and molecular analysis. Of the 132 somatic cell lines generated, 16 were identified as somatic hybrids, with
the phenotypes resembled B. scorzonerifolium parent. These hybrids showed a complete set of B. scorzonerifolium chromosome and 0–2 small chromosome(s) of A. thaliana. A few of them showed nuclear and cytoplasmic SSR fragments of A. thaliana. These hybrid cell lines could differentiate to green spots, buds/leaves through complementation of regeneration ability.
The chromosomes elimination of A. thaliana was discussed.
Wang Minqin and Zhao Junsheng contributed equally to the work. 相似文献
4.
The swan obtained by hybridization between Cygnus cygnus and C.olor was delivered to the Moscow Zoo from the Leningrad Zoo in 1989. Between 2002 and 2004, it permanently remained with a female
whooper swan in a large pond. The two swans behaved as a breeding pair, although the sex of the hybrid bird remained unknown.
We observed no courtship displays addressed by the hybrid swan either to the female whooper swan or to other swans living
in the pond. The hybrid swan was exteriorly closer to C. cygnus rather than to C. olor and showed increased aggressiveness. Its threatening behavior was intermediate between parental species in terms of threat
displays and motor activity, although behavioral patterns characteristic of C.olor prevailed. The most frequent sounds in the vocal repertoire of the hybrid swan were close to the vibrant throbbing call of
C.olor in terms of duration and frequency range. In contrast to these sounds, the call of the hybrid swan was noiselike, with distinct
harmonic structure (as in the whooper swan except for extremely narrow interharmonic intervals). These vocal signals of the
hybrid swan were shown to be intermediate between those of the parental species. In addition, the acoustic repertoire of the
hybrid swan included rarely emitted sounds closely resembling elements of vocalizations of both C. cygnus and C. olor. 相似文献
5.
Coptotermes lacteus, a termite found in eastern Australia, is a central-site nester that constructs mounds up to 2 m in height. Mature colonies
typically contain the primary king and queen, and up to a million or more worker and soldier offspring. Once a year, male
and female nymphs are produced in approximately equal numbers and develop into new alates. Experimental removal of the queen
in the field and subsequent mating of the king with a replacement queen, results in an unusual phenomenon whereby the production
of female nymphs completely ceases, while the production of male nymphs, and workers of both sexes, continues. The proximate
cause of this nymph male-bias is yet to be discovered. The production of male nymphs and workers of both sexes in de-queened
C. lacteus colonies is equivalent to offspring production patterns in laboratory crosses of male nymphoid (nymph-derived) with female
ergatoid (worker-derived) replacement reproductives in the related species Reticulitermes speratus. An X-linked genetically influenced caste determination (GCD) mechanism has been proposed to account for such offspring patterns
in R. speratus. We examined microsatellite genotypes in C. lacteus to test a prediction arising from the R. speratus GCD model: that nymphs should result from reproduction by neotenics, rather than the primary pair. In five of six colonies
examined, genotypes indicated that all workers and nymphs were derived from a single reproductive pair. In three of these
cases, the primary queen was also located and examined; her genotype matched that inferred from worker and nymph genotypes.
These results suggest that the GCD model proposed for R. speratus does not apply to C. lacteus, at least under field conditions. The male-nymph bias following queen removal therefore remains an unresolved issue in C. lacteus. 相似文献
6.
The reproductive ecology of the gobiid fish Bathygobius fuscus was studied at Nobeoka, Miyazaki, Japan. Males of this species maintain small rock holes as a nest and females spawn an egg
mass on the wall of the nest. The males employed two forms of mating tactic: nest holding and sneaking. A nest holder stayed
in the nest and waited for a female to visit, whereas a sneaker intruded into a nest while a pair was engaged in reproduction.
Males larger than 55 mm standard length were always nest holders; those of smaller size employed both tactics. As the larger
males excluded the smaller males, the latter did not occupy a nest hole. With a decrease in the number of larger males, smaller
males changed their mating tactic from sneaking to nest holding. The results suggest that male Bathygobius fuscus adopt a conditional strategy whereby they change their tactic depending on their social status.
Electronic Publication 相似文献
7.
de Mello Martins F Gifalli-Iughetti C Koiffman CP Harris EE 《Primates; journal of primatology》2011,52(1):77-87
We have used coalescent analysis of mtDNA cytochrome b (cyt b) sequences to estimate times of divergence of three species of Alouatta—A. caraya, A. belzebul, and A. guariba—which are in close geographic proximity. A. caraya is inferred to have diverged from the A. guariba/A. belzebul clade approximately 3.83 million years ago (MYA), with the later pair diverging approximately 1.55 MYA. These dates are
much more recent than previous dates based on molecular-clock methods. In addition, analyses of new sequences from the Atlantic
Coastal Forest species A. guariba indicate the presence of two distinct haplogroups corresponding to northern and southern populations with both haplogroups
occurring in sympatry within Sao Paulo state. The time of divergence of these two haplogroups is estimated to be 1.2 MYA and
so follows quite closely after the divergence of A. guariba and A. belzebul. These more recent dates point to the importance of Pleistocene environmental events as important factors in the diversification
of A. belzebul and A. guariba. We discuss the diversification of the three Alouatta species in the context of recent models of climatic change and with regard to recent molecular phylogeographic analyses of
other animal groups distributed in Brazil. 相似文献
8.
Speciation studies seek to clarify the origin of reproductive isolation, the various mechanisms working from mate recognition
through postzygotic stages. Asymmetric effects of isolating barriers can result in asymmetrical gene introgression during
interspecific hybridization. The flightless ground beetles Carabus yamato and C. albrechti are distributed parapatrically in Japan, showing repeated asymmetrical introgression of mitochondria from C. albrechti to C. yamato. This pattern suggests that reproductive isolation between these species is strong, but incomplete and asymmetric (i.e.,
weaker for the cross between a C. albrechti female and a C. yamato male). To test this hypothesis, we conducted interspecific mating experiments in the laboratory. The estimates of total reproductive
isolation, which occurred mainly at the premating and postmating/prezygotic stages, were high (isolation index = 0.964 for
C. yamato female × C. albrechti male and 0.886 for the reciprocal cross), supporting the hypothesis of strong, but incomplete isolation. However, the observed
difference between the reciprocal crosses was not sufficiently large to conclude that it caused directional introgression
of mitochondria. Instead, we found asymmetry in individual isolating barriers in the postmating/prezygotic stages that coincided
with the prediction, perhaps resulting from morphological mismatch of heterospecific genitalia. Although this asymmetry was
compensated for by an inverse asymmetry of isolation in the postzygotic stage, the contribution of these individual barriers
to total isolation may change for our expectation when considering females mating with multiple heterospecific males. 相似文献
9.
Physiological data from extreme habitat organisms during stresses are vital information for comprehending their survival.
The intertidal seaweeds are exposed to a combination of environmental stresses, the most influential one being regular dehydration
and re-hydration. Porphyra katadai var. hemiphylla is a unique intertidal macroalga species with two longitudinally separated, color distinct, sexually different parts. In
this study, the photosynthetic performance of both PSI and PSII of the two sexually different parts of P. katadai thalli during dehydration and re-hydration was investigated. Under low-grade dehydration the variation of photosystems of
male and female parts of P. katadai were similar. However, after the absolute water content reached 42%, the PSI of the female parts was nearly shut down while
that of the male parts still coordinated well and worked properly with PSII. Furthermore, after re-hydration with a better
conditioned PSI, the dehydrated male parts were able to restore photosynthesis within 1 h, while the female parts did not.
It is concluded that in P. katadai the susceptibility of photosynthesis to dehydration depends on the accommodative ability of PSI. The relatively lower content
of phycobiliprotein in male parts may be the cause for a stronger PSI after severe dehydration. 相似文献
10.
We performed comparative analyses of four cross-sections of the distal radius and tibia in two species of macaque to clarify
the relationships between bone morphology and locomotor type. The lengths of bones and five bone geometric properties in each
section were examined and compared separately in both female and male Macaca mulatta and Macaca fascicularis. In M. mulatta, there were no significant gender-specific differences in either the radius or the tibia. In contrast, the radius and tibia
of male M. fascicularis had greater geometric parameters in the 20% and 40% positions relative to the 5% and 10% positions from the distal end than
those of their female counterparts. The radius and tibia of M. mulatta were relatively longer than those of M. fascicularis, and the sectional parameters of the tibia of M. mulatta were relatively larger than those of M. fascicularis. Standardization of the log-transformed bone length between the species revealed larger radial cortical bone areas in M. fascicularis. In contrast, there were minimal differences in the tibial cortical bone areas between the two species. This study suggests
that the observed distinctions in bone geometry in female and male M. fascicularis may be due to gender-specific differences in the muscle weights of the forearm and calf, which may underlie the divergence
in the leaping abilities of females and males of this species. Taken together, these results of interspecies comparisons may
be related to the fact that arboreal primates such as M. fascicularis undergo compressive mechanical stress due to the forelimb lead that occurs as the animal descends a sloping trunk or bridges
a tree gap downward, while terrestrial primates such as M. mulatta move on nearly flat substrates. Differences in fore- and hind-limb bone properties between the two species are discussed
with regard to functional morphology and locomotor type. 相似文献
11.
ITS sequences determined for 53 Erysiphe specimens on Syringa and Ligustrum collected in Europe, East Asia, and North and South America were divided into two ITS groups, S and K types. Phylogenetic
analysis showed that these two ITS types do not share a common ancestor and form separate clades. The K type on Ligustrum was identified as Erysiphe ligustri based on the three-dimensional branching pattern of appendages. Morphological observations showed that there are some morphological
differences—pigmentation of appendages and number of ascospores per ascus—between the S and K types on Syringa. Based on these morphological observations, the S and K types on Syringa were identified as E. syringae and E. syringae-japonicae, respectively. The recent abundant production of chasmothecia by lilac powdery mildew in Europe was caused by E. syringae-japonicae introduced from East Asia. DNA sequence analyses of the rDNA ITS region and the 28S rDNA, tub2, CYP51, and Chs1 genes did not support an interspecific hybrid origin for E. syringae-japonicae. Haplotype analysis suggested that E. syringae originated in North America and independently migrated to East Asia and Europe/South America. 相似文献
12.
Genetic hybridization analysis was conducted with 16 natural Zygowilliopsis strains isolated in different geographical regions and maintained in collections under species names Z. californica, Hansenula dimennae, and Pichia populi. Genetic relatedness was determined on the basis of mating, viability of hybrid progeny, and meiotic recombination of markers.
Four new biological species are recognized in the former monotypic genus Zygowilliopsis. Species Z. californica and Zygowiliopsis sp. 3 probably include divergent geographical populations. It is necessary to reconsider the species composition of the genus
Zygowiliopsis and generic assignment of P. populi yeasts. Genetic and molecular identifications of the Zygowiliopsis species are in perfect agreement. 相似文献
13.
The number and position of 18S–25S rDNA sites in 4 selected Lupinus species are reported for the first time. L. atlanticus, L. subcarnosus and L. paniculatus had two rDNA loci, while L. albus exhibited only one loci. Among these 4 species, all of them exhibited one large pair of strong signals that extends from
the short arm to a NOR on a chromosome satellite. L. atlanticus, L. subcarnosus, L. paniculatus had one more locus of 18–25S rDNA, but a pair of weak hybridization signals were observed in L. paniculatus when 18S–25S rDNA was used as probe. The results are discussed in terms of the evolutionary relationships among these species. 相似文献
14.
15.
Quantitative trait loci (QTL) detection was carried out for adventitious rooting and associated propagation traits in a second-generation
outbred Corymbia torelliana × Corymbia citriodora subspecies variegata hybrid family (n = 186). The parental species of this cross are divergent in their capacity to develop roots adventitiously on stem cuttings
and their propensity to form lignotubers. For the ten traits studied, there was one or two QTL detected, with some QTL explaining
large amounts of phenotypic variation (e.g. 66% for one QTL for percentage rooting), suggesting that major effects influence
rooting in this cross. Collocation of QTL for many strongly genetically correlated rooting traits to a single region on linkage
group 12 suggested pleiotropy. A three locus model was most parsimonious for linkage group 12, however, as differences in
QTL position and lower genetic correlations suggested separate loci for each of the traits of shoot production and root initiation.
Species differences were thought to be the major source of phenotypic variation for some rooting rate and root quality traits
because of the major QTL effects and up to 59-fold larger homospecific deviations (attributed to species differences) relative
to heterospecific deviations (attributed to standing variation within species) evident at some QTL for these traits. A large
homospecific/heterospecific ratio at major QTL suggested that the gene action evident in one cross may be indicative of gene
action more broadly in hybrids between these species for some traits. 相似文献
16.
N. Yu. Markelova 《Microbiology》2010,79(6):777-779
Interaction of Bdellovibrio bacteriovorus 100NCJB with bacteria Campylobacter jejuni (strains 1, 2, 3, 4, and 5) and Helicobacter pylori, strain TX30a, was confirmed. The results indicate that lytic activity of bdellovibrios both in liquid media and cells attached
to a surface was observed. The potential use of the antimicrobial activity of predatory bacteria for environmental bioprotection
and public health is discussed. 相似文献
17.
Alloparental behavior is documented for several anthropoid primates, but few researchers have investigated the extent or variability
of such behavior in prosimians. We report results from a study of male-infant interactions in 2 groups of Coquerel’s sifaka
(Propithecus verreauxi coquereli) at the Duke University Primate Center (DUPC). Both groups contained 1 adult pair, 2 juveniles, and a newborn. The adult males
exhibited paternal behavior toward their offspring in the form of grooming and holding the infant, though males differed in
the amount of time they spent engaged in these activities. Group differences in the proximity maintained between the infants’
parents suggest that the relationship between adult males and females may help account for the variation. The presence of
juveniles appeared to diminish paternal behavior in the group exhibiting a higher overall rate of male-infant interaction. 相似文献
18.
There are three most important bacterial causative agents of serious infections that could be misused for warfare purposes:
Bacillus anthracis (the causative agent of anthrax) is the most frequently mentioned one; however, Fracisella tularensis (causing tularemia) and Yersinia pestis (the causative agent of plague) are further bacterial agents enlisted by Centers for Disease Control and Prevention into the category A of potential biological weapons. This review intends to summarize basic information about these bacterial
agents. Military aspects of their pathogenesis and the detection techniques suitable for field use are discussed. 相似文献
19.
Romina Pavé Martin M. Kowalewski Silvana M. Peker Gabriel E. Zunino 《Primates; journal of primatology》2010,51(3):221-226
Parent–offspring conflict has been scarcely studied in Neotropical primates. In this study, we explored mother–offspring conflict
in a group of wild black and gold howler monkeys (Alouatta caraya) in northeastern Argentina. We used the all-occurrences technique to record behaviors, completing 712 h of observation. The
results showed that all immature individuals between 2 and 23 months expressed conflict with regard to suckling or traveling
with their mothers. Successful suckling attempts negatively correlated with the age of the immatures, occurring least frequently
with the presence of newborns. In the juvenile period, the decline in successful attempts was a consequence of juveniles reducing
suckling attempts and mother rejection. 相似文献
20.
Using molecular karyotyping and genetic hybridization analysis, two new polymeric β-fructosidase genes, SUC9 and SUC10, were identified in the yeast Saccharomyces cerevisiae, which are located on chromosome XIV and on the chromosome XVI/XIII doublet, respectively. The genes are responsible for
fermentation of sucrose and raffinose. The SUC gene genotypes of strains VKM Y-1831 and DBVPG 1340 are SUC2 SUC9 and suc2
0
SUC10, respectively. suc2
0 is a silent sequence. The scientific and applied significance of SUC genes is discussed. 相似文献