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1.
Evolutionary Consequences of Fallback Foods   总被引:4,自引:2,他引:2  
Primatologists use the term fallback foods to denote resources of relatively low preference that are used seasonally when preferred foods are unavailable. We examine the assumption that fallback foods play an important role in shaping morphological adaptations, behavior, and socioecology in primates. We discuss operational definitions of preferred and fallback foods and suggest that the evolutionary importance of fallback foods applies more to adaptations for processing than for harvesting foods. Equally, we propose that preferred resources tend to drive adaptations for harvesting foods. We distinguish 2 classes of fallback foods according to their roles in the diet and their evolutionary effects. Staple fallback foods are available year-round, tend to be eaten throughout the year, and seasonally can constitute up to 100% of the diet. Filler fallback foods never constitute 100% of the diet, and may be completely avoided for weeks at a time. We suggest that the availability of the 2 classes of fallback foods have different effects on the socioecology of primate species.  相似文献   

2.
Objectives : Despite the increasing availability of low‐ and reduced‐fat foods, Americans continue to consume more fat than recommended, which may be a contributing factor to the obesity epidemic. This investigation examined relationships between liking and household availability of high‐ and low‐fat foods and their association with dietary fat intake. Research Methods and Procedures : A food frequency questionnaire assessed percent calories from fat consumed over the past year in 85 men and 80 women. Participants reported their degree of liking 22 “high‐fat foods” (>45% calories from fat) and 22 “low‐fat foods” (<18% calories from fat), and the number and percentage (number of high‐ or low‐fat foods/total number of foods × 100) of these high‐ and low‐fat foods in their homes. Results : Hierarchical regression analyses examined the ability of liking and household availability of low‐ and high‐fat foods to predict percent dietary fat intake. After controlling for age, sex, and BMI, liking ratings for high‐ and low‐fat foods and the interaction of liking for low‐fat foods by the percentage of low‐fat foods in the household were significant predictors of percent dietary fat consumed. Greater liking of high‐fat foods and lower liking of low‐fat foods, both alone and combined with a lower percentage of low‐fat foods in the home, were predictive of higher dietary fat intake. Discussion : Interventions designed to reduce dietary fat intake should target both decreasing liking for high‐fat foods and increasing liking for low‐fat foods, along with increasing the proportion of low‐fat foods in the household.  相似文献   

3.
It is known that some foods cause an allergenic response in certain individuals. Clinical and immunological tests are available for the diagnosis of food allergy and identification of food allergens. However, there are no valid tests for the prediction of the allergenic potential of foods not normally recognized as allergenic. Such foods include: food products developed from foods which may not be recognizable as allergenic in their modified forms; foods produced using novel processes (novel foods), for example genetically modified foods; and foods not normally consumed but that are being used increasingly as alternatives to more traditional foods. Both the risks associated with food allergy and the fact that foods such as the ones described above will become available to the consumer, highlight the need for methods to screen for potential food allergens. This review provides a general overview of food allergy including mechanism, development and prevalence, but focuses on and discusses: 1) the possible risks (with specific reference to food allergy) associated with new and novel foods; and 2) the development/use of food allergy models (in vivo and in vitro) to assess the allergenic potential of new and novel foods.  相似文献   

4.
Physical anthropologists use the term “fallback foods” to denote resources of relatively poor nutritional quality that become particularly important dietary components during periods when preferred foods are scarce. Fallback foods are becoming increasingly invoked as key selective forces that determine masticatory and digestive anatomy, influence grouping and ranging behavior, and underlie fundamental evolutionary processes such as speciation, extinction, and adaptation. In this article, we provide an overview of the concept of fallback foods by discussing definitions of the term and categorizations of types of fallback foods, and by examining the importance of fallback foods for primate ecology and evolution. We begin by comparing two recently published conceptual frameworks for considering the evolutionary significance of fallback foods and propose a way in which these approaches might be integrated. We then consider a series of questions about the importance of fallback foods for primates, including the extent to which fallback foods should be considered a distinct class of food resources, separate from preferred or commonly eaten foods; the link between life history strategy and fallback foods; if fallback foods always limit primate carrying capacity; and whether particular plant growth forms might play especially important roles as fallback resources for primates. We conclude with a brief consideration of links between fallback foods and primate conservation. Am J Phys Anthropol 140:603–614, 2009. © 2009 Wiley-Liss, Inc.  相似文献   

5.
The development of functional foods: lessons from the gut   总被引:1,自引:0,他引:1  
Functional foods have resulted from the gradual recognition that healthy diets result from eating nutritious foods and from the identification of the mechanisms by which foods modulate metabolism and health. After initial successes with foods that reduce blood cholesterol level, probiotic bacteria and prebiotic carbohydrates have now also demonstrated added health benefits. As ingredients become more complex, the need to stabilize such ingredients in foods become increasingly important to the success of functional foods. Modern biotechnologies such as genomics, genetic expression and biomarkers of health and performance will be applied to this increasingly visible portion of human diets.  相似文献   

6.
We investigated responses toward novel foods and novel objects by wild capuchins that routinely exploit visitors' foods in Brasília National Park. Given the capuchins' daily exposure to human foods and objects, we expected them to be more explorative toward novel foods and objects compared to capuchins that are not habituated to visitors. However, since the safety and palatability of potential foods have to be learned, we also expected the capuchins to be cautious about eating novel foods, as has been reported for wild and captive capuchins. Stimuli were presented on a platform in four experimental conditions: familiar food (FF), novel food (NF), familiar food plus novel object (FF+O), and novel food plus novel object (NF+O). Latencies to approach and contact the platform, and to approach and to ingest food did not differ across conditions. Nevertheless, the capuchins were significantly more responsive (measured in terms of interest, manipulation, etc.) toward familiar foods than novel foods, and ate significantly more of the former. In other words, their explorative response toward novel foods led to little consumption. Our results do not support the "readiness to eat" hypothesis, according to which a lower readiness to eat and food neophobia are the consequences of the presence of a distracting novel object. The finding that capuchins explore novel stimuli but remain cautious about eating novel foods supports the view that neophilia and neophobia are motivationally independent responses.  相似文献   

7.
蜜源食物对节肢动物天敌寿命、繁殖力和控害能力的影响   总被引:1,自引:0,他引:1  
大多数节肢动物天敌除了寄生或捕食寄主或猎物外,也会取食蜜源食物,特别是包括植物花蜜、花外蜜和昆虫蜜露等富含糖分的食物。这些蜜源食物对于提高寄生性和捕食性天敌的飞行和寄主搜索能力、延长寿命、提高繁殖力和增强控害能力都能发挥重要作用。本文重点介绍了农田生态系统中3类常见的非猎物性蜜源食物即植物花蜜、花外蜜和昆虫蜜露。其中,花蜜和花外蜜能够显著延长天敌寿命,提高天敌繁殖力和控害能力;蜜露的作用虽次于花蜜和花外蜜,但仍能促进某些天敌的生态功能。还进一步综述了显花植物和蜜源食物投放在生物防治中的应用,并从筛选适宜的蜜源植物、蜜源食物中糖成分作用分析和天敌对蜜源食物的搜索和定位等方向开展对蜜源食物的研究利用进行了展望。  相似文献   

8.
The selenium content of some frequently consumed foods from a commercial beef packer, a road-side vendor, and local stores in Lubbock, Texas was determined and compared to selenium data for the same or similar foods in the United States and from other countries. The comparative content of selenium in foods covered the period of time between 1970 and 1993. Our selenium analyses of foods show that on a fresh weight basis, the selenium content of seafoods > commercial beef>pork>ground beef>chicken. Cooking, air-or freeze-drying increased the selenium content of all foods significantly. When the selenium content of local foods is compared to similar foods in the United States and other countries, with few exceptions, there exists great uniformity in the selenium content in the major food groups, meats, fish, milk, and vegetables. New Zeal-and, known for its low soil selenium, had the lowest comparative food selenium content.  相似文献   

9.
In recent times, the status of some fermented foods which are considered as functional foods that confer health benefits in certain disease conditions has grown rapidly. The health benefits of fermented foods are due to the presence of probiotic microbes and the bioactive compounds formed during fermentation. Microbes involved and metabolites produced by them are highly species specific and contribute to the authenticity of the fermented foods. Several studies pertaining to the effect of fermented foods on various disease conditions have been conducted in recent years using both animal models and clinical trials on humans. This review focuses on the impact of fermented foods on conditions such as diabetes, cardiovascular disease, obesity, gastrointestinal disorder, cancer and neurodegenerative disorders.  相似文献   

10.
Abstract. To investigate the ability of insects to discriminate between nutritionally balanced and unbalanced foods, fifth-instar nymphs of Locusta migratoria L. (Orthoptera: Acrididae) were given one of thirteen pairings of artificial foods differing only in their concentration of protein and carbohydrate. One food, containing a previously estimated optimum balance of these nutrients, was common to each pairing. The relative intake of this 'target' food increased on the more extreme pairings, i.e. the insects demonstrated increasingly strong preference for the balanced food when it was paired with unbalanced alternative foods. When distinctive non-nutritional flavours (tannic acid and amygdalin) were added to one or both of the foods, the insects' intake of the unbalanced foods increased, particularly on high-protein foods. It is suggested that learned associations were not involved in the observed patterns of selection and that the added flavours disrupted the chemosensory responses to nutrients used by the insects to differentiate foods in this context.  相似文献   

11.
Many tropical animals inhabit mosaic landscapes including human-modified habitat. In such landscapes, animals commonly adjust feeding behavior, and may incorporate non-natural foods. These behavioral shifts can influence consumers' nutritional states, with implications for population persistence. However, few studies have addressed the nutritional role of non-natural food. We examined nutritional ecology of wild blue monkeys to understand how dietary habits related to non-natural foods might support population persistence in a mosaic landscape. We documented prevalence and nutritional composition of non-natural foods in monkey diets to assess how habitat use influenced their consumption, and their contribution to nutritional strategies. While most energy and macronutrients came from natural foods, subjects focused non-natural feeding activity on five exotic plants, and averaged about a third of daily calories from non-natural foods. Most non-natural food calories came from non-structural carbohydrates and least from protein. Consumption of non-natural foods related to time in human-modified habitats, which two groups used non-randomly. Non-natural and natural foods were similar in nutrients, and the amount of non-natural food consumed drove variation in nutritional strategy. When more daily calories came from non-natural foods, females consumed a higher ratio of non-protein energy to protein (NPE:P). Females also prioritized protein while allowing NPE:P to vary, increasing NPE while capitalizing on non-natural foods. Overall, these tropical mammals achieved a similar nutrient balance regardless of their intake of non-natural foods. Forest and forest-adjacent areas with non-natural vegetation may provide adequate nutrient access for consumers, and thus contribute to wildlife conservation in mosaic tropical landscapes.  相似文献   

12.
There is growing recognition of the contribution of wild foods to local diets, nutrition, and culture. Yet disaggregation of understanding of wild food use by gender and age is limited. We used a mixed methods approach to determine the types, frequencies, and perceptions of wild foods used and sold by children in four villages in southern Malawi that have different levels of deforestation. Household and individual dietary diversity scores are low at all sites. All households consume one or more wild foods. Across the four sites, children listed 119 wild foods, with a wider variety at the least deforested sites than the most deforested ones. Older children can name more wild foods than younger ones. More children from poor households sell wild foods than from well-off households. Several reasons were provided for the consumption or avoidance of wild foods (most commonly taste, contribution to health, limited alternatives, hunger, availability, local taboos).  相似文献   

13.
The objective of this study was to gather data on the incidence of Clostridium botulinum spores in selected consumer-convenience food products. The incidence of spores of C. botulinum in 100 samples of each of four categories of commercially available convenience foods was determined. These categories included (i) "boil-in-the-bag" foods, (ii) vacuum-packed foods, (iii) pressurized foods, and (iv) dehydrated and freeze-dried foods. Of the 400 samples analyzed, one was found to contain the spores of C. botulinum. This occurred in vacuum-packed frank-furters and was identified as type B.  相似文献   

14.
Exploitation of anthropogenic foods has profound effects on various aspects of the behavior and ecology of nonhuman primates. On the Cape Peninsula, South Africa, incentives to exploit novel resources are high and most local chacma baboons (Papio ursinus) feed on anthropogenic foods. Here we investigate the foraging profile, activity budget, and ranging behavior of a Peninsula group that feeds exclusively on natural foods. We predicted that the group would exploit the marine foods available to them and feed more extensively on subterranean foods, spend more time feeding and traveling, and occupy a larger area and travel further than groups that feed on anthropogenic foods, and groups elsewhere that occupy highly productive habitats. We tracked the group using handheld GPS units, and recorded behavioral data using instantaneous scan sampling in four seasons through 13 months. Our predictions were supported with the study group feeding on marine foods during all for seasons, but allocating a small percentage (<5%) of their total feeding time to exploiting these foods. Also, the group used a greater area (45.3 km2) and traveled further (5.9 km/day), and allocated more time to feeding and traveling, than previously studied groups on the Peninsula that exploit anthropogenic foods. These findings highlight behavioral variation in baboons associated with anthropogenic food use. Comparison of our results with those reported elsewhere should allow management authorities to more accurately predict changes in behavior of cercopithecoid monkeys as their access to anthropogenic foods is gradually restricted.  相似文献   

15.
Of the foods offered to gerbils Tatera indica , whole seeds and sweet foods were preferred. Finely divided foods were clearly disliked. Oily mixtures also failed to attract them.  相似文献   

16.
取经中性红活染后的杆吻虫喂水螅,仔细观察了水螅的摄食行为.结果表明,水螅垂唇端部能够相互识别出同类;水螅的垂唇与胃区能协力把杆吻虫吞入胃腔,触手经常随食物进入胃腔;吞食时经常出现头部内翻或外翻;个体间及其成体与芽体间常出现争夺食物的现象,当垂唇端部互不相触时,体型较大的个体常常把较小个体或芽体连同食物一起吞食;垂唇内胚层腺细胞对食物有消化作用,对同类无伤害;水螅的神经系统已有初步的整合功能.  相似文献   

17.
食品中重金属的存在形态及其与毒性的关系   总被引:15,自引:6,他引:15  
简要介绍了近年来有关食品中重金属形态及其毒性关系的研究进展,归纳了食品中重金属的化学形态特征、不同类型食品中重金属的存在形态、食品中重金属形态与生物有效性和毒性的关系,以及该领域中急需研究解决的问题.  相似文献   

18.
The results from simple choice test experiments with laboratory and field colonies of pharaoh's ants have revealed two behavioural traits that influence the way in which foraging worker ants respond to foods. Initially, worker ants from laboratory colonies showed a distinct preference for certain foods (e.g. honey and peanut butter). However, when given only these 'preferred' foods continuously for several weeks, workers showed a marked preference for other foods when offered a choice. This 'satiation' response occurred even though the initial diet was originally highly attractive to foraging workers. In addition, workers show a marked tendency to alternate between carbohydrate foods and protein foods. Thus, workers from colonies fed predominantly on proteins, subsequently showed a marked preference for carbohydrates, and vice versa. The 'satiation' and 'alternation' responses to foods ensure that colonies receive a diet that is both varied and balanced. In addition, these aspects of feeding behaviour have important consequences for the use of food-based baits in control measures against Monomorium pharaonis (L.).  相似文献   

19.
Objectives: To evaluate the association between high‐level functional capacity and chewing in a middle‐old community‐based population. Background: Although basic and instrumental activities of daily living are known to be associated with chewing ability in the elderly, an association between higher levels of competence and chewing ability has not been evaluated in the elderly. Materials and methods: The association between chewing ability using a number of different foods and high‐level functional capacity by the Tokyo Metropolitan Institute of Gerontology was evaluated in 694, 80‐year‐old people residing in Fukuoka Prefecture, Japan. Results: A significant correlation was found, using multiple regression or logistic regression analyses adjusted for various confounding factors, between the number of total chewable foods, hard foods or moderately hard foods, and total functional capacity, instrumental activity, intellectual activity or social role ability. In contrast, the number of slightly hard foods, easily chewable foods and remaining teeth were only partly related to total functional capacity and intellectual activity. Conclusion: High‐level functional capacity including intellectual activity and social role in middle‐old elderly was associated with the ability to chew hard foods than to chew easily chewable foods. Maintenance of chewing ability in elderly might result in better intellectual activity and social role.  相似文献   

20.
Recent progresses in data-driven analysis methods, including network-based approaches, are revolutionizing many classical disciplines. These techniques can also be applied to food and nutrition, which must be studied to design healthy diets. Using nutritional information from over 1,000 raw foods, we systematically evaluated the nutrient composition of each food in regards to satisfying daily nutritional requirements. The nutrient balance of a food was quantified and termed nutritional fitness; this measure was based on the food’s frequency of occurrence in nutritionally adequate food combinations. Nutritional fitness offers a way to prioritize recommendable foods within a global network of foods, in which foods are connected based on the similarities of their nutrient compositions. We identified a number of key nutrients, such as choline and α-linolenic acid, whose levels in foods can critically affect the nutritional fitness of the foods. Analogously, pairs of nutrients can have the same effect. In fact, two nutrients can synergistically affect the nutritional fitness, although the individual nutrients alone may not have an impact. This result, involving the tendency among nutrients to exhibit correlations in their abundances across foods, implies a hidden layer of complexity when exploring for foods whose balance of nutrients within pairs holistically helps meet nutritional requirements. Interestingly, foods with high nutritional fitness successfully maintain this nutrient balance. This effect expands our scope to a diverse repertoire of nutrient-nutrient correlations, which are integrated under a common network framework that yields unexpected yet coherent associations between nutrients. Our nutrient-profiling approach combined with a network-based analysis provides a more unbiased, global view of the relationships between foods and nutrients, and can be extended towards nutritional policies, food marketing, and personalized nutrition.  相似文献   

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