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1.
Low micronutrient intake is implicated in a diversity of human health problems, ranging from problems associated with food insufficiency to those associated with food over-consumption. Humans are members of the order primates, suborder anthropoidea, and are most closely related to the great apes. Humans and apes are remarkably similar biologically. In the wild, apes and monkeys consume diets composed largely of plant foods, primarily the fruits and leaves of tropical forest trees and vines. Considerable evidence indicates that the ancestral line giving rise to humans (Homo spp.) was likewise strongly herbivorous (plant-eating). The wild plant parts consumed by apes and monkeys show moderate to high levels of many minerals and vitamins. The estimated daily intake of specific minerals, vitamin C and some other vitamins by wild primates is often quite high in comparison to intake levels of these same micronutrients recommended for humans. Are the high micronutrient intakes of wild primates simply a non-functional, unavoidable by-product of their strongly plant-based diets or might they actually be serving important as yet undetermined immunological or other beneficial functions? A better understanding of the basis for this apparent difference between humans and wild primates could help to clarify the range and proportions of micronutrients best suited for optimal human development, health and longevity.  相似文献   

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Ecologists and conservation biologists seem increasingly attracted to sophisticated modelling approaches, sometimes at the expense of attention to data quality and appropriateness of fieldwork design. This dissociation may lead to a loss of perspective promoting biological unrealities as conclusions, which may be used in conservation applications. We illustrate this concern by focusing on recent attempts to estimate population size of breeding birds at large scales without any explicit testing of the reliability of the predictions through comparison with direct counts. Disconnection of analysts from “nature” can lead to cases of biological unrealities such as that used here to illustrate such trends. To counter this risk, we encourage investment in well-rounded scientists or more collaborative, multi-disciplinary teams capable of integrating sophisticated analyses with in-depth knowledge of the natural history of their study subjects.  相似文献   

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The urgency of the tropical biodiversity crisis continues to be a major justification for wildlife research and its funding. To examine the benefits of this research for on-the-ground conservation, we focused on Borneo, where conservation has a long history and we have direct experience. We compiled, categorized and evaluated 284 publications from a broad variety of sources, 153 from peer-reviewed journals. We found that few studies address threats to species and fewer still provide input for or guidance to effective management. We consider various reasons for these shortcomings. Research is seldom judged on its relevance to pragmatic problem solving. Furthermore, many research programs lack the necessary long-term vision and organizational structure for useful applied research. We consulted conservation leaders about our conclusions and all responses suggest that our concerns are not unique to Borneo but reflect wider problems. We conclude that conservation research across most of the tropics is failing to address conservation needs. We make a number of recommendations based on our findings. Conservation biologists should place a higher priority on addressing practical conservation needs and goals.  相似文献   

4.
Hybridization between wild boar (Sus scrofa) and domestic pig occurred in the past and still occurs today, having great evolutionary and management implications. In fact, genetic introgression from the domestic form may alter traits like behavior, reproduction rate, and immunology in wild populations, with likely demographic impacts. Thus, it is crucial to understand under what conditions hybridization occurs in S. scrofa. Captive crosses with domestic pigs (released or escaped) have been suggested to constitute the major source of the spread of domestic genes into wild boar populations. However, to date, few studies have assessed the degree of admixture in farmed animals in comparison to the surrounding wild populations. With this purpose, we analyzed microsatellite loci in wild boar sampled in breeding stations and in the local wild population in two Italian regions (Sardinia and Piedmont). Both captive populations had lower allelic richness than the corresponding wild population, but a similar expected heterozygosity. In Piedmont, introgression from the domestic form into the wild population seems to be extremely low, while there are significant signs of admixture in the sampled breeding stations. In Sardinia, instead, the captive sample did not differ significantly from the wild population, which showed moderate signs of introgression. We conclude that hybridization in nature seems to play the key role in Sardinia, while intentional hybridization in captivity is the major source of introgression in Piedmont. Our findings emphasize the need for a routine genetic monitoring of wild boar captive populations, coupled with reference data on the neighboring wild populations.  相似文献   

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The present review underlines the knowledge of Cryptosporidium, especially its biodiversity and transmission. The presence of the parasite in different mammal host species is discussed with real, potential risk of transmission to humans. The potential role of insects in mechanical transmission of the parasite is evaluated by experimental protocols. The cost of cryptosporidiosis at health and economic levels are mentioned, which emphasises the importance of detection and identification of the parasite in the environment and in wild mammal species, using specific molecular tools. Potential measures to be accomplished in order to fight off cryptosporidiosis are also noted.  相似文献   

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A gradual alteration in the mechanisms underlying reproduction and fertility characterizes the aging process in human females. These changes culminate in menopause, conventionally defined as a cessation of menstrual cycles that marks the end of reproductive capacity. In fact, a central and defining event in menopause is the discontinuation of ovulation, which is correlated with a number of structural and functional changes in the reproductive axis. Despite several decades of research, a degree of uncertainty remains as to whether nonhuman primates undergo menopause, and whether they are suitable models of human reproductive senescence. We review some of the controversies that have clouded our understanding of reproductive aging in nonhuman primates, including issues of definition, timing, comparability of data from wild versus captive populations, and cross-species comparisons. The existing data support the view that menopause occurs in a number of primate species and is not unique to humans.  相似文献   

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Is a wild mammal kept and reared in captivity still a wild animal?   总被引:1,自引:0,他引:1  
This study compared domestic guinea pigs (Cavia aperea f. porcellus; DGP) and two different populations of the wild cavy (Cavia aperea), its ancestor, to examine whether rearing of wild mammals in captivity affects their behavior and physiological stress responses. One population of wild cavies consisted of wild-trapped animals and their first laboratory-reared offspring (WGP-1). The animals of the other population were reared in captivity for about 30 generations (WGP-30). The spontaneous behavior of each of six groups of WGP-1 and WGP-30 and nine groups of DGP, each consisting of one adult male and two adult females, was analyzed quantitatively. Blood samples of the males were taken to determine cortisol, epinephrine, and norepinephrine concentrations. In addition, the exploratory behavior of 60-day-old male WGP-1, WGP-30, and DGP was investigated in an exploration apparatus. The domesticated animals displayed significantly less aggression, but significantly more sociopositive and male courtship behavior than their wild ancestors. In addition, DGP were much less attentive to their physical environment. Surprisingly, no behavioral difference was found between WGP-1 and WGP-30. Basal cortisol concentrations did not differ between wild and domestic guinea pigs. Catecholamine concentrations, however, as well as the challenge values of cortisol, were distinctly reduced in the DGP. WGP-1 and WGP-30 did not differ with respect to their endocrine stress responses. In the exploration apparatus both forms of wild cavies were much more explorative than the domestic animals. These data suggest that the long-term breeding and rearing of wild guinea pigs in captivity do not result in significant changes in behavior and hormonal stress responses. It appears to take much longer periods of time and artificial selection by humans to bring about characters of domestication in wild animals.  相似文献   

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Spondyloarthropathy is a painful arthritic affliction of humans that also occurs in wild mammals. Important questions remain concerning the underlying causes of spondyloarthropathy in mammals, particularly regarding whether it is infectious in origin or driven by genetic predisposition and environmental stressors. Moreover, spondyloarthropathy has negative effects on host fitness, leading to potential conservation concerns if it impacts threatened species. Using a comparative data set on the prevalence of joint disease in 34 primate species and 100 carnivore species, we tested predictions involving the epidemiological correlates of spondyloarthropathy in wild mammals. Analyses revealed that 5.6% of primates and 3.6% of carnivores exhibited signs of spondyloarthropathy, with maximum incidence as high as 22% in great apes and 27% in bears. We tested whether prevalence of spondyloarthropathy increases with population density and group size, greater contact with soil, a slower host life history, increased ranging, dietary factors and body mass. We found general support for an effect of body mass, with larger bodied primates and carnivores exhibiting a higher prevalence of spondyloarthropathy. In addition, more threatened species experienced higher rates of spondyloarthropathy, with this association influenced by body mass and phylogeny. The effect of body mass could reflect that larger animals are exposed to more pathogens through greater consumption of resources, or that joints of larger bodied mammals experience greater biomechanical stresses, resulting in inflammation and activation of local joint infections.  相似文献   

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Behavior and conservation: a bridge too far?   总被引:2,自引:0,他引:2  
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The taxonomic rank of subspecies remains highly contentious, largely because traditional subspecies boundaries have sometimes been contradicted by molecular phylogenetic data. The most complete meta-analysis to date, for instance, found that only 3% of traditional avian subspecies represented distinct phylogenetic lineages. However, the global generality of this phenomenon remains unclear due to this previous study's narrow geographic focus on continental Nearctic and Palearctic subspecies. Here, we present a new global analysis of avian subspecies and show that 36% of avian subspecies are, in fact, phylogenetically distinct. Among biogeographic realms we find significant differences in the proportion of subspecies that are phylogenetically distinct, with Nearctic/Palearctic subspecies showing significantly reduced levels of differentiation. Additionally, there are differences between island and continental subspecies, with continental subspecies significantly less likely to be genetically distinct. These results indicate that the overall level of congruence between taxonomic subspecies and molecular phylogenetic data is greater than previously thought. We suggest that the widespread impression that avian subspecies are not real arises from a predominance of studies focusing on continental subspecies in North America and Eurasia, regions which show unusually low levels of genetic differentiation. The broader picture is that avian subspecies often provide an effective short-cut for estimating patterns of intraspecific genetic diversity, thereby providing a useful tool for the study of evolutionary divergence and conservation.  相似文献   

18.

Background

A gender-based disparity in physical activity (PA) among youth, whereby girls are less active than boys is a persistent finding in the literature. A greater understanding of the mechanisms underlying this difference has potential to guide PA intervention strategies.

Methods

Data were collected at age 8 and 12 years (276 boys, 279 girls) from 29 schools as part of the LOOK study. Multilevel linear models were fitted separately for boys and girls to examine effects of individual, family and environmental level correlates on pedometer measured PA. Cardio-respiratory fitness (multi-stage run), percent fat (DEXA), eye-hand coordination (throw and catch test) and perceived competence in physical education (questionnaire) were used as individual level correlates. At the family level, parent’s support and education (questionnaire) were used. School attended and extracurricular sport participation were included as environmental level correlates.

Results

Girls were 19% less active than boys (9420 vs 11360 steps/day, p<0.001, 95%CI [1844, 2626]). Lower PA among girls was associated with weaker influences at the school and family levels and through lower participation in extracurricular sport. School attended explained some of the variation in boys PA (8.4%) but not girls. Girls compared to boys had less favourable individual attributes associated with PA at age 8 years, including 18% lower cardio-respiratory fitness (3.5 vs 4.2, p<0.001, CI [0.5,0.9]), 44% lower eye-hand coordination (11.0 vs 17.3, p<0.001, CI [5.1,9.0]), higher percent body fat (28% vs 23%, p<0.001, CI [3.5,5.7]) and 9% lower perceived competence in physical education (7.7 vs 8.4, p<0.001, CI [0.2,0.9]). Participation in extracurricular sport at either age 8 or 12 years was protective against declines in PA over time among boys but not girls.

Conclusion

Girls PA was less favourably influenced by socio-ecological factors at the individual, family, school and environmental levels. These factors are potentially modifiable suggesting the gap in PA between boys and girls can be reduced. Strategies aiming to increase PA should be multicomponent and take into consideration that pathways to increasing PA are likely to differ among boys and girls.  相似文献   

19.
We tested whether mixotrophic ciliates are more resistant to solar ultraviolet radiation (UVR) than heterotrophic ones because symbiotic algae can provide self-shading by cell matter absorption and eventually by direct UV screening from mycosporine-like amino acids (MAAs). Sensitivity of a natural assemblage to solar radiation was tested in experiments in the original lake and in a more UV transparent alpine lake after transplantation of the ciliates. In both lakes, the assemblage was exposed either to full sunlight, to photosynthetically active radiation only, or kept in the dark. In each lake, exposure was for 5 h at the surface and at the depth corresponding to the 10% attenuation depth at 320 nm. Overall, when the assemblage was exposed to surface UVR, only one out of four dominant mixotrophic ciliates, Vorticella chlorellata, was more resistant than heterotrophic species. The higher UV resistance in V. chlorellata was related to the presence of MAAs and the high percentage of ciliate volume occupied by algal symbionts. Our results indicate that effects of UVR were species-specific and depended on efficient screening of these wavelengths, but also on the depth preference of the ciliates and thus, on their previous exposure history to UVR.  相似文献   

20.
Predation on livestock is a cause of serious and long-lasting conflict between farmers and wildlife, promoting negative public attitudes and endangering conservation of large carnivores. However, while large carnivores, especially the grey wolf (Canis lupus), are often blamed for killing sheep and other farm animals, free-ranging dogs may also act as predators. To develop appropriate measures for livestock protection, reliable methods for identifying predator species are critical. Identification of predators from visual examination of livestock wounds can be ambiguous and genetic analysis is strongly preferable for accurate species determination. To estimate the proportion of wolves and dogs implicated in sheep predation, we developed a sensitive genetic assay to distinguish between wolves and domestic dogs. A total of 183 predator saliva samples collected from killed sheep in Estonia were analysed. The assay identified the predator species in 143 cases (78%). Sheep were most often killed by wolves (81%); however, predation by dogs was substantial (15%). We compared the molecular results with field observations conducted by local environmental officials and recorded some disagreement, with the latter underestimating the role of dogs. As predator saliva samples collected from prey are often of poor quality, we suggest using mitochondrial DNA as a primary tool to maximise the number of successfully analysed samples. We also suggest adopting forensic DNA analysis more widely in livestock predation assessments as a legislative measure since misidentification that is biased against wolves can be counterproductive for conservation by enhancing conflict with society and leading to increased culling and poaching.  相似文献   

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