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1.
This study investigated the effects of parity and age on female rhesus macaque attention toward infants, and assessed whether the faces of neonates are more attractive than those of older infants. Six nulliparous and six multiparous females were shown digitized images of neonates’ and 5- to 6-month-old infants’ faces. Attention and preferences for images were measured by gaze duration and other picture-directed behaviors, including lip smacking, approaches, and presentations. As predicted, nulliparous females displayed significantly longer gaze durations for images than did multiparous females. There were no significant differences in gaze duration for faces of neonates and those of infants, but images of infants were approached more frequently than images of neonates. This difference is tentatively explained on the basis of differences in female familiarity with neonates’ and infants’ faces and differences in opportunities for allomothering with neonates and infants.  相似文献   

2.
Four bred grapevine varieties released for commercial cultivation in Ukraine, namely ‘Antey Magarachskii’, ‘Rubinovyi Magaracha’, ‘Granatovyi Magaracha’ and ‘Rubin Golodrigi’, and their putative parental forms were genotyped using six microsatellite loci. Genotypes were compared with breeding records to verify genetic relationships among varieties. Results of the analysis confirmed four of six parent-offspring relationships. Results of the analysis allow to assume that genotype ‘Seyve Villard 20347’ is the direct parent of ‘Antey Magarachskii’ instead of its grandparent. The first-studied accession believed to be that of ‘Granatovyi Magaracha’ was identified as impurity. In order to verify the parentage of ‘Granatovyi Magaracha’, rest accessions of that variety and its putative parent ‘Antey Magarachskii’ were additionally genotyped at 13 nuclear loci and at three chloroplast loci. The parent-offspring relationship was confirmed, as all ‘Granatovyi Magaracha’ accessions had a common allele with the parent variety ‘Antey Magarachskii’ at each locus and the same chlorotype A. Different ‘Granatovyi Magaracha’ accessions could have been obtained via vegetative propagation of two seedlings which arose from one crossing.  相似文献   

3.
According to the approach developed by Thomas A. Sebeok (1921–2001) and his ‘global semiotics,’ semiosis and life converge. This leads to his cardinal axiom: ‘semiosis is the criterial attribute of life.’ His global approach to sign life presupposes his critique of anthropocentrism and glottocentrism. Global semiotics is open to zoosemiotics, indeed, even more broadly, biosemiotics which extends its gaze to semiosis in the whole living universe to include the realms of macro- and microorganisms. In Sebeok’s conception, the sign science is not only the study of communication in culture, but of communicative behaviour from a biosemiotic perspective.  相似文献   

4.
Many estimates of ‘marine protected area (MPA) effects’ may be confounded by environmental heterogeneity between MPA and ‘Control’ sites. However, the magnitude and extent of such confounding is generally unknown. Here, the effects of microhabitat availability on estimates of MPA performance were explicitly explored. Abundance of a reef fish species, Ctenochaetus striatus (Quoy & Gaimard, 1825), available microhabitat, and, microhabitat preference for C. striatus within six ‘Ra’ui’ (traditionally managed MPAs) and six paired ‘Control’ sites on the island of Rarotonga, Cook Islands, were estimated. Response ratios accounting for available microhabitat qualitatively modified inferences of Ra’ui effectiveness for two of the six Ra’ui when contrasted with response ratios not accounting for available microhabitat. However, analysis of covariance (ANCOVA) indicated that available microhabitat accounted for significant variation in C. striatus densities between Ra’ui and Control, rather than protection. Our results suggest that adjusting for microhabitat availability may significantly alter our perception of the effects of Ra’ui on C. striatus. Our framework, in concert with our ANCOVA models, provides a stronger assessment of MPA effects. Further, we conclude that metrics of environmental heterogeneity should be incorporated into future assessments of MPA effectiveness, with our work describing one potential framework to accomplish this.  相似文献   

5.
This study analyzed genetic differences of 19 cultivars selected from somaclonal variants of Syngonium podophyllum Schott along with their parents as well as seven additional Syngonium species and six other aroids using amplified fragment length polymorphism (AFLP) markers generated by 12 primer sets. Among the 19 somaclonal cultivars, ‘Pink Allusion’ was selected from ‘White Butterfly’. Tissue culture of ‘Pink Allusion’ through organogenesis resulted in the development of 13 additional cultivars. Self-pollination of ‘Pink Allusion’ obtained a cultivar, ‘Regina Red Allusion’, and tissue culture propagation of ‘Regina Red Allusion’ led to the release of five other cultivars. The 12 primer sets generated a total of 1,583 scorable fragments from all accessions, of which 1,284 were polymorphic (81.9%). The percentages of polymorphic fragments within ‘White Butterfly’ and ‘Regina Red Allusion’ groups, however, were only 1.2% and 0.4%, respectively. Jaccard's similarity coefficients among somaclonal cultivars derived from ‘White Butterfly’ and ‘Regina Red Allusion’, on average, were 0.98 and 0.99, respectively. Seven out of the 15 cultivars from the ‘White Butterfly’ group and three out of six from the ‘Regina Red Allusion’ group were clearly distinguished by AFLP analysis as unique fragments were associated with respective cultivars. The unsuccessful attempt to distinguish the remaining eight cultivars from the ‘White Butterfly’ group and three from the ‘Regina Red Allusion’ group was not attributed to experimental errors or the number of primer sets used; rather it is hypothesized to be caused by DNA methylation and/or some rare mutations. This study also calls for increased genetic diversity of cultivated Syngonium as they are largely derived from somaclonal variants.  相似文献   

6.
7.
Summary Anthers and ovaries of six grapevine cultivars (three Vitis vinifera L., two V × Labruscana L. H. Bailey, and one complex hybrid) were extracted from flower buds over 2 yr and cultured on three media reported to promote somatic embryogenesis in Vitis tissues. The highest percent embryogenesis from the hybrid ‘Chancellor’ and V. vinifera ‘Chardonnay’, ‘Merlot’, and ‘Pinot Noir’ occurred on medium C [Nitsch and Nitsch, 1969, basal medium with 3.0% (w/v) sucrose, 0.01% (w/v) inositol. 0.3% (w/v) Phytagel, 2.5 μM 2.4-dichlorophenoxyacetic acid, 2.5μM β-naphthoxyacetic acid, 5.0μM N-(2-chloro-4-pyridyl)-N′-phenylurea, and 0.05% (w/v) glutamine]. Regardless of the media, the labrusca cultivars ‘Concord’ and ‘Niagara’ produced soft non-embryogenic callus that was sometimes mixed with well-developed somatic embryos. Nine vinifera genotypes were further tested for several different years on medium C. Embryogenic cultures suitable for transformation were obtained from all genotypes in more than 1 yr. The average percent embryogenesis from ovaries was 7-fold higher than from anthers. There was significant annual variation in percent embryogenesis, demonstrating the need for media comparisons to be replicated for more than one season. Suspension cultures suitable for use in genetic transformation were initiated from ‘Chardonnay’, ‘Merlot,’ and ‘Pinot Noir’ pro-embryogenic masses. ‘Chardonnay’ suspension cultures plated and grown under conditions developed for recovery of plants after biolistic transformation yielded approximately 500 non-transformed embryos per plate after 4 mo. of culture, with 68.6% of the embryos converting to plants. This is the first reported protocol for embryogenesis from ‘Concord,’ ‘Cabernet Franc,’ and ‘Pinot Noir’ grapevines.  相似文献   

8.
In this review, three main experimental approaches for studying animal language behaviour are compared: (1) direct decoding of animals’ communication, (2) the use of intermediary languages to communicate with animals and (3) application of ideas and methods of the Information Theory for studying quantitative characteristics of animal communication. Each of the three methodological approaches has its specific power and specific limitations. Deciphering animals’ signals reveals a complex picture of natural communication in its evolutionary perspective but only fragmentary because of many methodological barriers, among which low repeatability of standard living situations seems to be a bottleneck. Language-training experiments are of great help for discovering potentials of animal language behaviour but leaves characteristics of their natural communications unclear. The use of the methods of Information Theory is based on measuring the time duration that animals spend on transmitting messages of definite information content and complexity. This approach, although does not reveal the nature of animals’ signals, provides a new dimension for studying important characteristics of natural communication systems, which have not been available before. First of all, this approach enables explorers of animals’ language behaviour to obtain knowledge just about the ability of subjects for transferring meaningful messages. Besides, the important properties of animal communication and intelligence can be evaluated such as the rate of information transmission, the complexity of transferred information and potential flexibility of communication systems.  相似文献   

9.
When an indigenous insect becomes a pest, comparisons of performance of pest and non-pest populations on crop plants and of genetic variation in that performance may provide insight into the evolution of pest populations. To measure such genetic variation, 8–15 clones of the grape phylloxera (Daktulosphaira vitifoliae Fitch) were collected from wild grapevines in each of 3 geographically isolated sites (populations) and from commercial vineyards in northern California. A complete life table was made for clonal replicates from populations collected from wild grapevines on each of two commercial grape cultivars, the susceptibleVitis vinifera (L.) cultivar Cabernet Sauvignon, and the phylloxera-resistant rootstock ‘AxR # 1’. Variation in mean performance on these two hosts was partitioned among clones within collection sites and among sites. Performance measures included an individual analog to the intrinsic rate of increase (r), age at first oviposition, fecundity in the first ten days of reproduction, total fecundity, and longevity. The overall performance of phylloxera from the wild grapevines on the resistant cultivar AxR # 1 was greater than or equal to that on the susceptible cultivar Cabernet Sauvignon. There was significant variation among clones within populations from wild grapes in the rate of increase on ‘AxR # 1’ and marginally significant clonal variation in some of the component paramters. There was no significant variation among clones within populations on ‘Cabernet Sauvignon’ and no significant differences between populations on either crop in any trait. In a second experiment we compared the relative performance of 15–17 clones from wild grapevines and from commercial vineyards when reared on ‘Cabernet Sauvignon’ and ‘AxR # 1’. Phylloxera from commercial vineyards had much higher overall performance on ‘Cabernet Sauvignon’ than did phylloxera from the wild grapevines. Phylloxera from the commercial vineyard also had higher performance on ‘Cabernet Sauvignon’ than on ‘AxR′ 1’ but the performance of the phylloxera from wild and commercial grapes did not differ on ‘AxR # 1’. Our results show that there is genetic variation in traits related to performance on a resistant rootstock within these indigenous non-pest populations of phylloxera, but not among them. The pattern of performance of pest and non-pest populations on two commercial cultivars suggests that current levels of phylloxera performance on crop cultivars are the result of adaptation to those cultivars which has occurred while phylloxera has been associated with viticulture. Implications of these results for understanding the recent adaptation of phylloxera to ‘AxR # 1’ in California are also discussed.  相似文献   

10.
Communal nursing in the domestic cat has been observed in group living conditions. (In high density conditions, cats have social lives.) In our laboratory, when females were kept in the same cage, they delivered kittens nearly simultaneously, and started to nurse their kittens communally. This process, which was videotaped, was shown to be begun by the mother’s retrieving kittens. They seemed to have no ability to discriminate their own kittens from those of others, as our test of recognition of kittens showed. Communal nursing resulted in high mortality of kittens, the release of mothers from caring for kittens, and incomplete reproductive division of labour. Abortion was often observed in group-living cats in captivity. High mortality and low birthrate are helpful in controlling population. All members of the group were very familiar to each other, so that they formed a ‘pseudo’-kin group.  相似文献   

11.
Many rice cultivars that originated from lower-latitude regions exhibit a strong photoperiod sensitivity (PS) and show extremely late heading under long-day conditions. Under natural day-length conditions during the cropping season in Japan, the indica rice cultivar ‘Nona Bokra’ from India showed extremely late heading (202 days to heading) compared to the japonica cultivar ‘Koshihikari’ (105 days), from Japan. To elucidate the genetic factors associated with such extremely late heading, we performed quantitative trait locus (QTL) analyses of heading date using an F2 population and seven advanced backcross progeny (one BC1F2 and six BC2F2) derived from a cross between ‘Nona Bokra’ and ‘Koshihikari’. The analyses revealed 12 QTLs on seven chromosomes. The ‘Nona Bokra’ alleles of all QTLs contributed to an increase in heading date. Digenic interactions were rarely observed between QTLs. Based on the genetic parameters of the QTLs, such as additive effects and percentage of phenotypic variance explained, these 12 QTLs are likely generate a large proportion of the phenotypic variation observed in the heading dates between ‘Nona Bokra’ and ‘Koshihikari’. Comparison of chromosomal locations between heading date QTLs detected in this study and QTLs previously identified in ‘Nipponbare’ × ‘Kasalath’ populations revealed that eight of the heading date QTLs were recognized nearby the Hd1, Hd2, Hd3a, Hd4, Hd5, Hd6, Hd9, and Hd13. These results suggest that the strong PS in ‘Nona Bokra’ was generated mainly by the accumulation of additive effects of particular alleles at previously identified QTLs.  相似文献   

12.
 Previous studies have established that chloroplasts are inherited paternally in Actinidia interspecific crosses. However, fertilisation problems in interspecific crosses may affect the transmission of organelles. Six female clones, i.e. ‘Abbott’, ‘Bruno’, ‘Greensill’, ‘Hayward’, ‘Jones’, ‘Monty’, and four male clones were used to identify cpDNA polymorphisms within the cultivated kiwifruit species A. deliciosa. The restriction patterns by HpaII of a chloroplast fragment amplified by PCR with a pair of universal primers revealed a polymorphism at the intraspecific level. The inheritance of cpDNA in 143 seedlings from three intraspecific crosses in kiwifruit (Actinidia deliciosa) was studied. All offspring displayed the restriction pattern of the paternal parent, indicating that maternal inheritance of cpDNA in kiwifruit is rare at best. Strict maternal inheritance of mtDNA was confirmed in the same crosses used to investigate cpDNA transmission. Studies of cytoplasmic inheritance in the Actinidia genus represent to date the best documented report of differential organelle inheritance of cpDNA and mtDNA in angiosperms. Received: 10 November 1998 / Accepted: 14 December 1998  相似文献   

13.
This article argues that organisms, defined by a semi-permeable membrane or skin separating organism from environment, are (must be) semiotically alert responders to environments (both Innenwelt and Umwelt). As organisms and environments complexify over time, so, necessarily, does semiotic responsiveness, or ‘semiotic freedom’. In complex environments, semiotic responsiveness necessitates increasing plasticity of discernment, or discrimination. Such judgements, in other words, involve interpretations. The latter, in effect, consist of translations of a range of sign relations which, like metaphor, are based on transfers (carryings over) of meanings or expressions from one semiotic ‘site’ to another. The article argues that what humans describe as ‘metaphor’ (and believe is something which only pertains to human speech and mind and, in essence, is ‘not real’) is, in fact, fundamental to all semiotic and biosemiotic sign processes in all living things. The article first argues that metaphor and mind are immanent in all life, and are evolutionary, and, thus, that animals certainly do have minds. Following Heidegger and then Agamben, the article continues by asking about the place of animal mind in humans, and concludes that, as a kind of ‘night science’, ‘humananimal’ mind is central to the semiotics of Peircean abduction.  相似文献   

14.
Betelvine (Piper betle L., family Piperaceae) is an important, traditional and widely cultivated crop of India. The cultivators and consumers recognize more than 100 cultivars (landraces) based on regional and organoleptic considerations, while in terms of phytochemical constituents only five groups have been identified for all the landraces. Since betelvine is an obligate vegetatively propagated species, genomic changes, if any, may have become ‘fixed’ in the landraces. We carried out random amplified polymorphic DNA (RAPD) analysis in several landraces considered in four groups, namely, ‘Kapoori’, ‘Bangla’, ‘Sanchi’ and ‘Others’ in order to ascertain their genetic diversity. On the basis of the data from eleven RAPD primers, we distinguished genetic variation within and among the four groups of landraces. The results indicate the’Kapoori’ group is the most diverse. The neighbour joining (NJ) tree after a bootstrap (500 replicate) test of robustness clearly shows the four groups to be well separated. Interestingly, all known male or female betelvine landraces have separated in the NJ tree indicating an apparent gender-based distinction among the betelvines.  相似文献   

15.
The alginates extracted from ‘leaf’, ‘stem’ and entire thallus of Turbinaria conoides (J.Ag.) Kütz. were investigated for their viscosity and biochemical constituents namely, β-D-mannuronic acid (M-block}), α-L-guluronic acid (G-Block) and alternating sequences of β–D-mannuronic acid and α-L-guluronic acid (MG-block). Substantial seasonal variation was recorded with high yield of alginate during premonsoon. The yield of alginate was maximum in ‘leaf’ region. In contrast to this, viscosity and G-block were maximum in the ‘stem’ region. A significant positive correlation was observed between viscosity and G-block}. The ratio of guluronic: mannuronic acid was also assessed. Low levels of M/G ratio were recorded in the ‘stem’ region followed by ‘leaf’ and entire thallus.  相似文献   

16.
The effects of six basal media on in vitro shoot proliferation of the greek grapevines Vitis vinifera L. cv. ‘Malagouzia’ and ‘Xinomavro’ were investigated. Galzy and Zlenco proved to be the most effective for ‘Malagouzia’ and ‘Xinomavro’, respectively. If only BA was present in the medium, shoot development was poor and the plantlets were chlorotic. When the medium was supplemented with BA and NAA, growth was enhanced. The best ratio (in μM) of growth regulators was 0.5/0.3 for ‘Malagouzia’, and 0.1/0.03 for ‘Xinomavro’, which resulted in the highest number of microshoots per explant and greatest proliferation rate. The development of ‘Malagouzia’ and ‘Xinomavro’ explants at 21±2 and 26±2°C was also investigated, revealing the higher temperature to be more effective. Regarding rooting, 0.5 μM IBA improved root formation at 26°C for ‘Malagouzia’ and 0.5 μM IBA at 21°C for ‘Xinomavro’. Moreover, 0.5 μM IBA resulted in a higher rooting percentage (>95%) and proved to be more beneficial for the overall morphological appearance of the plantlets of ‘Malagouzia’. After acclimatization, survival of microshoots cultivated in media with IBA was higher than those in NAA.  相似文献   

17.
The invasion of native habitats by exotic, or alien, plant species has received considerable attention recently from policy, research, and practical conservation management perspectives. However, a new hypothesis for species dynamics in Britain suggests that a small number of aggressive native plant species (termed ‘thugs’) may have an equal, or greater, impact on native species and habitats than exotic species. Here, we examine this hypothesis using multivariate techniques with field-layer cover data collected during a country-wide survey of British woodlands. Multivariate analysis of these data identified a north-south gradient on the first axis, and that 20 of the 25 National Vegetation Classification woodland types were sampled within the study. The most abundant field-layer species included three of the proposed native ‘thugs’, i.e. Rubus fruticosus, Pteridium aquilinum and Hedera helix in addition to the native woodland indicator species Mercurialis perennis. Variation partitioning was used to compare the relative importance of native field-layer ‘thug’ species with invading alien shrub and tree species relative to other environmental drivers. The variation in the field-layer data-set explained by the three native ‘thug’ species was significant, but they explained a relatively small proportion of the variation relative to other environmental variables (climate, soil, management factors etc.). They did, however, explain almost four times as much variation as the three alien species that were significantly correlated with field-layer species composition (Acer pseudoplatanus, Impatiens glandulifera, Rhododendron ponticum). The results of this analysis suggest that the field-layer of British woodlands is impacted as much by native ‘thug’ species, as it is from ‘aliens’. Concern about the impact of these native ‘thug’ species has been reported previously, but their impact has not previously been compared to the impact of invading aliens. It is hoped that this analysis will do two things, first to act as a sound baseline for assessing any changing balance that should occur in the future, and second, to prompt both ecologists and conservationists to develop woodland management policies based on sound science.  相似文献   

18.
The objective of this paper is the structural and narrative reconstruction of representations of ‘nature’, ‘wildlife’ and ‘landscape’, held by rural residents of the Dadia Forest Reserve. Data collection involved in-depth interviews. Employing a social representations’ approach, we recovered representational elements that are expected in the case of rural belief systems, such as negative dispositions towards wolves and foxes, as well as elements of an urban adherence, such as nature’s independence. Representational elements refer to visual aspects of the countryside, which seem compatible with the figurative nucleus of the rural idyll. Concerning ‘wildlife’, residents focused on vultures, which comprise the main tourist attraction of the reserve. Scientific knowledge adds to the complexity of the narrative schema, which corresponds to the representation of ‘wildlife’. Interviewees perceived the rural landscape as an interface between the natural and the human-conditioned environment. Our study shows that interviewees make no reference to environmental conservation or quality of life issues, as it could be expected according to relatively wide definitions of the term ‘environmentalism’. Environmental messages reinforced by ecotourism development seem to be recalled primarily in terms of their compatibility with the perceived economic benefit of local people. Despite ecotourism development, representational elements that diverge from a tourist version of ‘nature’, ‘wildlife’ and ‘landscape’ were not pronounced within rural belief-systems. Further interventions within the study area are needed, in order to address a variety of topics under the environmental conservation discourse and raise the environmental awareness of rural residents.  相似文献   

19.
Mutual gaze occurs when two animals simultaneously look at each other, and therefore signals reciprocal visual attention. We studied the occurrence of mutual gaze among adult female Japanese monkeys (Macaca fuscata) housed at the Central Park Zoo in New York City (USA). We found that the frequency of mutual gaze varied according to one aspect of social context (proximity), and that monkeys’ age-rank was negatively correlated with the frequency of mutual gaze. The behavioral contexts in which mutual gaze was observed did not include aggression, and social rank did not predict frequency of mutual gaze. Mutual gaze therefore varies according to some aspects of social context and is generally predicted by factors that influence other social behaviors (e.g., age).  相似文献   

20.
The objective of this study was to examine whether S-RNase plays a specific role in the pre-germinated Pyrus pollen. Effects of exogenous RNase and endogenous S-RNase on concentration of cytosolic-free calcium ([Ca2+]i) variation of pre-germinated Pyrus pollen were studied. [Ca2+]i variation caused by different RNases were complex. In 1 h after being cultured, exogenous RNase, RNase T1 and RNase A, and endogenous incompatible ‘Hohsui’ RNase promoted the [Ca2+]i of ‘Hohsui’ pollen. Acid proteins of ‘Hohsui’ had no remarkable influence on the [Ca2+]i of self-pollen. Endogenous compatible ‘Kohsui’ RNase reduced the [Ca2+]i of ‘Hohsui’ pollen, but compatible ‘Hohsui’ RNase can stimulate the [Ca2+]i of ‘Kohsui’ pollen. RNase T1, RNase A and incompatible ‘Kohsui’ S-RNase can also make ‘Kohsui’ pollen [Ca2+]i increase. Different from ‘Hohsui’ pollen, acid proteins of ‘Hohsui’ pull down the ‘Kohsui’ pollen [Ca2+]i remarkably. Conclusion can be made that during the prophase of pollen germination, endogenous S-RNase has no specific effect on pollen [Ca2+]i changes.  相似文献   

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