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Hordeum spontaneum, wild barley, is the direct progenitor of domestic barley, Hordeum vulgare, an economically important ingredient of animal feed, beer, soy sauce, and more recently, of nutraceuticals. Domestic barley has also been used in the past as a medicine. Barley is a rich source of tocotrienols, with α-tocotrienol being the most prevalent. Wild barley seeds were harvested from ecogeographically diverse areas across the Fertile Crescent, and the tocopherol (α-δ) and tocotrienol (α-δ) contents were determined. Diversity differences in individual and total 'tocol' values were significant between and within specific countries, and were significantly correlated with temperature. Wild barley may be used in the future to improve functional qualities of domestic barley. 'Tocolome' and 'tocolomics' are proposed to encompass all tocols and potentially synergy-enhancing 'entourage' compounds that may occur in tocols' 'metabolomic neighborhoods', aiding the standardized manufacture of complex barley derivatives for nutraceutical and pharmaceutical functions.  相似文献   

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J. Weldon  McNutt 《Journal of Zoology》1996,240(1):163-173
Parental care of unrelated young is occasionally misdirected and maladaptive from an individual fitness perspective (e.g. interspecific brood parasitism). Alternatively, adults may'adopt'dependent young and gain direct benefits irrespective of the degree of relatedness. For social species whose fitness is partially a function of group size, direct benefits of increasing group size may provide a mechanism favouring adoption independently of the inclusive fitness consequences. African wild dogs. Lycaon pictus , are social carnivores for which group size has been positively crrelated with reproductive success and competitive ability. Co-operative breeding by wild dogs has been described previously as strongly kin-selected and helpers were assumed to be invariably closely related to offspring. However, observations from this study show that the assumption that helpers are related to those they help is not always valid. A minimum of 25% of study area packs ( n =12) contained nonbreeding adults that provided parental care for unrelated pups. Costs of adopting unrelated weaned wild dog pups are slight or nonexistent except for delayed costs due to later potential conflict with mature same-sex adoptees over access to mates. Immediate and delayed direct benefits identified here are associated with increasing group size and may indicate important mechanisms underlyig adoption and the evolution of helping behaviour in wild dogs.  相似文献   

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In the decade since the first draft of the human genome was announced, genome sequencing projects have been initiated for an additional twenty-some primate species. Within the next several years, genome sequence data will likely become available for all primate genera and for most individuals within some primate populations. At the same time, gene mapping and association studies of humans and other organisms are rapidly advancing our understanding of the genetic bases of behavioral and morphological traits. Primatologists are especially well-placed to take advantage of this coming flood of genetic data. Here we discuss what this new era of primate genomics means for field primatology and highlight some of the unprecedented opportunities it will afford, particularly with regard to examining the genetic basis of primate adaptation and diversity.  相似文献   

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Fifty-seven wild boars (Sus scrofa) from protected regions of Iran were examined for helminths. Sixteen species of helminths were collected; there were ten nematodes, one acanthocephalan, two trematodes and three larval cestodes. New host and distribution records were established for all helminths except of Taenia solium cysticerci. Wild boar shared nine of these helminths with domestic pigs, six with ruminants and three with human beings in Iran. Metastrongylus pudendotectus and M. salmi are reported for the first time from Iran.  相似文献   

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Understanding trade‐offs in wild populations is difficult, but important if we are to understand the evolution of life histories and the impact of ecological variables upon them. Markers that reflect physiological state and predict future survival would be of considerable benefit to unraveling such trade‐offs and could provide insight into individual variation in senescence. However, currently used markers often yield inconsistent results. One underutilized measure is hematocrit, the proportion of blood comprising erythrocytes, which relates to the blood's oxygen‐carrying capacity and viscosity, and to individual endurance. Hematocrit has been shown to decline with age in cross‐sectional studies (which may be confounded by selective appearance/disappearance). However, few studies have tested whether hematocrit declines within individuals or whether low hematocrit impacts survival in wild taxa. Using longitudinal data from the Seychelles warbler (Acrocephalus sechellensis), we demonstrated that hematocrit increases with age in young individuals (<1.5 years) but decreases with age in older individuals (1.5–13 years). In breeders, hematocrit was higher in males than females and varied relative to breeding stage. High hematocrit was associated with lower survival in young individuals, but not older individuals. Thus, while we did not find support for hematocrit as a marker of senescence, high hematocrit is indicative of poor condition in younger individuals. Possible explanations are that these individuals were experiencing dehydration and/or high endurance demands prior to capture, which warrants further investigation. Our study demonstrates that hematocrit can be an informative metric for life‐history studies investigating trade‐offs between survival, longevity, and reproduction.  相似文献   

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The diet of zebrafish Danio rerio in Bangladesh consisted primarily of zooplankton and insects. Zebrafish was an annual species, with the main period of reproduction commencing just before the onset of the monsoon season. Growth rates varied with age and season, with the period of most rapid growth in early life during the monsoon months.  相似文献   

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To determine the genetic relationship of anadromous and resident life-history types within and among drainages, and compare several hatchery strains to their progenitor populations, brook charr Salvelinus fontinalis were examined for allozyme and mitochondrial DNA variation. Greater genetic similarity of sympatric anadromous and resident charr was found compared to similar life-history forms allopatrically, suggesting the two life-history types are not reproductively isolated. Low divergence among the mtDNA haplotypes suggests that the two life-history types are members of the same evolutionary lineage. Population differentiation from mtDNA data exceeded that from estimates based on allozymes. Genetic deviations from expectations suggest that the hatchery strains were derived from few individuals.  相似文献   

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Patterns of growth in wild bottlenose dolphins, Tursiops truncatus   总被引:2,自引:0,他引:2  
A. J. Read    R. S. Wells    A. A. Hohn    M. D. Scott 《Journal of Zoology》1993,231(1):107-123
The growth of bottlenose dolphins is described from observations made during a capture release programme that has operated in coastal waters of the eastern Gulf of Mexico from 1970 to the present. Measurements of standard length, girth and body mass were recorded from 47 female and 49 male dolphins, some captured as many as nine times. Ages were known from approximate birth dates or estimated from counts of dentinal growth layers. In all three measurements. females grew at a faster initial rate than males, but reached asymptotic size at an earlier age. This extended period of growth in males resulted in significant sexual dimorphism in length, girth and mass at physical maturity. The growth of both sexes was well described by three-parameter Gompertz models using either cross-sectional data or a mixture of longitudinal and cross-sectional data. There was considerable variation in size-at-age for both sexes in all year classes. Residuals of size measurements were used to derive measures of relative size for individual dolphins; most dolphins demonstrated little ontogenetic change in relative size. Body mass was adequately predicted by multiple regression equations that incorporated both length and girth as independent variables.  相似文献   

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Meat-eating was observed for the first time among a population of wild orang utans at Gunung Leuser National Park, Sumatra. An adult female who was consorting with an adult male consumed a gibbon (Hylobates lar) carcass. There was no food sharing between the consort pair. The absence of food sharing is interpreted as indicative of the anti-social attitude of adult orang utans.  相似文献   

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Farmed fish are typically genetically different from wild conspecifics. Escapees from fish farms may contribute one-way gene flow from farm to wild gene pools, which can depress population productivity, dilute local adaptations and disrupt coadapted gene complexes. Here, we reanalyse data from two experiments (McGinnity et al., 1997, 2003) where performance of Atlantic salmon (Salmo salar) progeny originating from experimental crosses between farm and wild parents (in three different cohorts) were measured in a natural stream under common garden conditions. Previous published analyses focussed on group-level differences but did not account for pedigree structure, as we do here using modern mixed-effect models. Offspring with one or two farm parents exhibited poorer survival in their first and second year of life compared with those with two wild parents and these group-level inferences were robust to excluding outlier families. Variation in performance among farm, hybrid and wild families was generally similar in magnitude. Farm offspring were generally larger at all life stages examined than wild offspring, but the differences were moderate (5–20%) and similar in magnitude in the wild versus hatchery environments. Quantitative genetic analyses conducted using a Bayesian framework revealed moderate heritability in juvenile fork length and mass and positive genetic correlations (>0.85) between these morphological traits. Our study confirms (using more rigorous statistical techniques) previous studies showing that offspring of wild fish invariably have higher fitness and contributes fresh insights into family-level variation in performance of farm, wild and hybrid Atlantic salmon families in the wild. It also adds to a small, but growing, number of studies that estimate key evolutionary parameters in wild salmonid populations. Such information is vital in modelling the impacts of introgression by escaped farm salmon.  相似文献   

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Human and nonhuman primates bond with one another in countless ways, and the results are varied and vital to the individuals and species involved. The manifesto that is the basis for the collection of essays in which this commentary is included proposes that the "human/nonhuman bonds that arise in primatological research and practice deserve and demand study and research." An essential corollary of this proposal is that the primatologists themselves must be studied. The aim of this essay is to explore the influence of human/nonhuman primate bonding on conservation practice and on the future of primates in the wild. This commentary applies the author's professional experience as a conservation psychologist and his research on the impact of profound interspecies bonds on human worldviews, attitudes, and behavior. It examines two general categories of bonds: those driven by Biophilia (human fascination with life) and those influenced by Biosynergy (mutual enrichment of life). It is the author's premise that biosynergy promotes complex collaborative interspecies bonds that broaden the conservationist's desire to enhance synergy among all organisms in an ecosystem. Conversely, biophilia induces relatively simple unidirectional bonds between humans and other animals that deepen the conservationist's desire to understand and protect certain species. This contrast raises some crucial questions. Do biophilia-driven bonds between conservationists and their favorite primates blind them to the synergistic needs of all species and impair their ability to work for sustained preservation of threatened habitat? Does biosynergy-based human/nature bonding enhance focus on conservation as an ecological science and thus ignore species-specific factors crucial to assure survival of endangered primates? How can both types of bonds be optimally applied to the conservation of wildlife and wilderness?  相似文献   

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Long-term field research has revealed that male chimpanzees, Pan troglodytes, affiliate and cooperate in several contexts. Assuming close genetic relationship among males, affiliative and cooperative behaviour have been hypothesized to evolve through the indirect effects of kin selection. We tested the hypothesis that matrilineal genetic relatedness affects patterns of male social affiliation and cooperation in an unusually large community of chimpanzees at the Ngogo study site, Kibale National Park, Uganda. Field observations indicated that six behavioural measures of affiliation and cooperation among 23 adult males were significantly correlated with each other. Sequences of the first hypervariable portion of the mtDNA genome revealed that three pairs of males and one quintet shared mtDNA haplotypes. Matrix permutation tests using behavioural and genetic data showed that males that affiliated and cooperated with each other were not closely related through the maternal line. These findings add to a growing body of empirical evidence that suggest kinship plays an ancillary role in structuring patterns of wild chimpanzee behaviour within social groups. Copyright 2000 The Association for the Study of Animal Behaviour.  相似文献   

17.
Wild boars shot in a hunting area in Baden-Württemberg during three consecutive years (148 males, 205 females) were analysed for insulin-like growth factor 1 (IGF-I) concentrations in blood plasma. Gonadal steroids were determined either in blood plasma (females, progesterone) or adipose tissue (males, androstenone). The age (estimated by the dental pattern) and the carcass weight were recorded. From 159 out of the 353 animals, the stomach content was analysed for total energy and digestibility. Sex differences in carcass weight were only significant in animals above the age of 14 months. Carcass weight was significantly correlated with IGF-I in males but not in females. IGF-I revealed a sex-specific seasonal pattern (maximum concentrations in males, June; in females, October). Additionally, as indicated by analyses of the stomach content, the digestibility of the food had affected IGF-I concentrations. Gonadal steroids revealed the well-known seasonal pattern described in other studies and did not point to a more aseasonal pattern of reproduction when energy supply is artificially increased by baiting.  相似文献   

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Lion tamarins (Callitrichidae: Leontopithecus) are small frugi-faunivores that defend large home ranges. We describe results from the first long-term investigation of wild golden-headed lion tamarins (L. chrysomelas; GHLTs). We present data about activity budgets, daily activity cycles, diet, daily path length, home range size, home range overlap, and territorial encounters for three groups of GHLTs that were studied for 1.5-2.5 years in Una Biological Reserve, Bahia State, Brazil, an area characterized by aseasonal rainfall. We compare our results to those from other studies of lion tamarins to identify factors that may influence foraging and ranging patterns in this genus. Ripe fruit, nectar, insects, and small vertebrates were the primary components of the GHLT diet, and gums were rarely eaten. Fruit comprised the majority of plant feeding bouts, and the GHLTs ate at least 79 different species of plants from 32 families. The most common foraging sites for animal prey were epiphytic bromeliads. The GHLTs defended large home ranges averaging 123 ha, but showed strong affinities for core areas, spending 50% of their time in approximately 11% of their home range. Encounters with neighboring groups averaged two encounters every 9 days, and they were always aggressive. Data about time budgets and daily activity cycles reveal that the GHLTs spent most of their time foraging for resources or traveling between foraging sites distributed throughout their home ranges. The GHLTs spent much less time consuming exudates compared to lion tamarins in more seasonal environments. Additionally, the GHLTs had much larger home ranges than golden lion tamarins (L. rosalia), and did not engage in territorial encounters as frequently as L. rosalia. GHLT ranging patterns appear to be strongly influenced by resource acquisition and, to a lesser extent, by resource defense.  相似文献   

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 Genetic diversity in random amplified polymorphic DNAs (RAPDs) was studied in 110 genotypes of the tetraploid wild progenitor of wheat, Triticum dicoccoides, from 11 populations sampled in Israel and Turkey. Our results show high level of diversity of RAPD markers in wild wheat populations in Israel. The ten primers used in this study amplified 59 scorable RAPD loci of which 48 (81.4%) were polymorphic and 11 monomorphic. RAPD analysis was found to be highly effective in distinguishing genotypes of T. dicoccoides originating from diverse ecogeographical sites in Israel and Turkey, with 95.5% of the 100 genotypes correctly classified into sites of origin by discriminant analysis based on RAPD genotyping. However, interpopulation genetic distances showed no association with geographic distance between the population sites of origin, negating a simple isolation by distance model. Spatial autocorrelation of RAPD frequencies suggests that migration is not influential. Our present RAPD results are non-random and in agreement with the previously obtained allozyme patterns, although the genetic diversity values obtained with RAPDs are much higher than the allozyme values. Significant correlates of RAPD markers with various climatic and soil factors suggest that, as in the case of allozymes, natural selection causes adaptive RAPD ecogeographical differentiation. The results obtained suggest that RAPD markers are useful for the estimation of genetic diversity in wild material of T. dicoccoides and the identification of suitable parents for the development of mapping populations for the tagging of agronomically important traits derived from T. dicoccoides. Received: 13 July 1998 / Accepted: 13 August 1998  相似文献   

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The results presented describe and compare the fatty acid composition and melting properties of captive, healthy wild, and pansteatitis-affected wild crocodiles (Crocodylus niloticus). Differences in fatty acid composition between intramuscular and adipose fat is noted in captive crocodiles, and the latter differs from wild crocodiles as a result of different diets. Adipose fat of healthy wild crocodiles differs minimally from diseased ones, respectively with 37.3 ± 2.6% vs. 43.2 ± 2.3% monounsaturated fatty acids, and 43.2 ± 2.9% in dead crocodiles, while polyunsaturated fatty acids decrease from 27.3 ± 1.9% to as low as 21.9 ± 3.6% respectively. Of the unsaturated fatty acids 18:2n? 6 decreased from 6.5 ± 2.6% in unaffected crocodiles to 3.5 ± 0.6% in highly affected and 3.2 ± 0.4% in dead crocodiles, and 22:5n?3 from 2.8 ± 0.6% to 1.8 ± 0.3% and 2.2 ± 0.3% respectively. The melting properties as determined by differential scanning calorimetry show that extracted adipose fat is a small degree softer in pansteatitis-affected tissue, specifically in the temperature range 7–36 °C, and does not contribute to the hard texture noted for adipose fat tissue of pansteatitis-affected animals. A high moisture content of 51.0 ± 19.7% of the fat tissue of pansteatitis-affected animals vs.17.1 ± 8.0% of healthy ones, suggests that physiological changes due to interstitial inflammation may contribute to the hard texture.  相似文献   

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