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Dietary Data (dietary + data)
Selected AbstractsTEMPORAL VARIATION IN DIVERGENT SELECTION ON SPINE NUMBER IN THREESPINE STICKLEBACKEVOLUTION, Issue 12 2002T. E. Reimchen Abstract., Short-term temporal cycles in ecological pressures, such as shifts in predation regime, are widespread in nature yet estimates of temporal variation in the direction and intensity of natural selection are few. Previous work on threespine stickleback (Gasterosteus aculeatus) has revealed that dorsal and pelvic spines are a defense against gape-limited predators but may be detrimental against grappling insect predators. In this study, we examined a 15-year database from an endemic population of threespine stickleback to look for evidence of temporal shifts in exposure to these divergent predation regimes and correlated shifts in selection on spine number. For juveniles, we detected selection for increased spine number during winter when gape-limited avian piscivores were most common but selection for decreased spine number during summer when odonate predation was more common. For subadults and adults, which are taken primarily by avian piscivores, we predicted selection should generally be for increased spine number in all seasons. Among 59 comparisons, four selection differentials were significant (Bonferroni corrected) and in the predicted direction. However, there was also substantial variability in remaining differentials, including two examples with strong selection for spine reduction. These reversals were associated with increased tendency of the fish to shift to a benthic niche, as determined from examination of stomach contents. These dietary data suggest that increased encounter rates with odonate predation select for spine reduction. Strong selection on spine number was followed by changes in mean spine number during subsequent years and a standard quantitative genetic formula revealed that spine number has a heritable component. Our results provide evidence of rapid morphological responses to selection from predators and suggest that temporal variation in selection may help maintain variation within populations. Furthermore, our findings indicate that variable selection can be predicted if the agents of selection are known. [source] A prospective study of dietary flavonoid intake and incidence of epithelial ovarian cancerINTERNATIONAL JOURNAL OF CANCER, Issue 10 2007Margaret A. Gates Abstract Flavonoids are antioxidant compounds found in plants, including fruits, vegetables and tea. No prior prospective studies have examined the association between intake of flavonoids in the flavonol and flavone subclasses and ovarian cancer risk. We analyzed the association between intake of 5 common dietary flavonoids and incidence of epithelial ovarian cancer among 66,940 women in the Nurses' Health Study. We calculated each participant's intake of myricetin, kaempferol, quercetin, luteolin and apigenin from dietary data collected at multiple time points, and used Cox proportional hazards regression to model the incidence rate ratio (RR) of ovarian cancer for each quintile of intake. Our analysis included 347 cases diagnosed between 1984 and 2002, and 950,347 person-years of follow-up. There was no clear association between total intake of the 5 flavonoids examined and incidence of ovarian cancer (RR = 0.75 for the highest versus lowest quintile, 95% confidence interval [CI] = 0.51,1.09). However, there was a significant 40% decrease in ovarian cancer incidence for the highest versus lowest quintile of kaempferol intake (RR = 0.60, 95% CI = 0.42,0.87; p -trend = 0.002), and a significant 34% decrease in incidence for the highest versus lowest quintile of luteolin intake (RR = 0.66, 95% CI = 0.49,0.91; p -trend = 0.01). There was evidence of an inverse association with consumption of tea (nonherbal) and broccoli, the primary contributors to kaempferol intake in our population. These data suggest that dietary intake of certain flavonoids may reduce ovarian cancer risk, although additional prospective studies are needed to further evaluate this association. If confirmed, these results would provide an important target for ovarian cancer prevention. © 2007 Wiley-Liss, Inc. [source] Dental pathology and diet at Apollonia, a Greek colony on the Black SeaINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 3 2008A. Keenleyside Abstract Dental pathology has the potential to provide insight into the composition of the diet and to reveal dietary differences based on age, sex and social status. Human skeletal remains from the Greek colonial site of Apollonia (5th to 2nd centuries BC) on the Black Sea coast of Bulgaria were analysed for various forms of dental pathology in order to: assess the prevalence of dental disease in the population; compare the dental pathology data from Apollonia with dietary data derived from ancient literary texts and from previous stable isotopic analysis of the colonists' remains; explore variations in dental disease with respect to age and sex; and compare the prevalence of dental pathology in the Apollonians with that of other Greek populations. The composition of the diet, as indicated by the dental pathology data, is consistent with the stable isotopic evidence from Apollonia and with the ancient literary texts, both of which indicate the consumption of a relatively soft, high carbohydrate diet. The higher frequency of dental caries, abscesses, calculus, and antemortem tooth loss in older adults compared with younger ones reflects the age-progressive nature of these conditions. The lack of significant sex differences in caries, abscesses, calculus and tooth loss corresponds with the stable carbon and nitrogen isotopic data derived from bone collagen, which indicate no significant sex differences in the consumption of dietary protein. In contrast, these findings conflict with the ancient literary texts, which refer to distinct dietary differences between males and females, and with the stable carbon isotopic values derived from bone carbonate, which indicate sex differences with respect to the overall diet. Despite the lack of marked sex differences in dental pathology, overall trends point to subtle dietary differences between males and females. A greater degree of tooth wear in males also hints at possible sex differences in the use of the teeth as tools. Copyright © 2007 John Wiley & Sons, Ltd. [source] Niche overlap between marsupial and eutherian carnivores: does competition threaten the endangered spotted-tailed quoll?JOURNAL OF APPLIED ECOLOGY, Issue 2 2008A. S. Glen Summary 1The significance of top-down regulation by carnivores is receiving increasing global recognition. As a consequence, key objectives in many programmes that seek to maintain ecosystem function now include conserving carnivores and understanding their interactions. This study examined overlap in resource use (space and diet) of introduced eutherian carnivores and an endangered marsupial carnivore, the spotted-tailed quoll Dasyurus maculatus, in eastern Australia. We also investigated mechanisms of niche partitioning and evidence for interspecific aggression. 2Dietary overlap between quolls, red foxes Vulpes vulpes and wild dogs Canis lupus ssp. was assessed by analysis of scats. Trapping, radio-tracking and direct observations were used to quantify spatial overlap between quolls, foxes, wild dogs and feral cats Felis catus. 3Dietary overlap among the carnivores was extensive. Medium-sized mammals were the most important prey for all three predators, indicating potential for exploitative interactions. However, hunting of different size classes of secondary prey and consumption by quolls of more arboreal prey than their counterparts may assist coexistence. Remains of quoll were found in two dog scats, and cat hair in another, possibly indicating intraguild predation. 4We observed extensive spatial overlap between quolls and eutherian carnivores. However, we inferred from dietary data that quolls foraged primarily in forested habitat, while canids foraged mainly in cleared habitat. 5Synthesis and applications. Our results indicate strong potential for competition between spotted-tailed quolls and eutherian carnivores, and thus a situation where control of introduced predators may be desirable, not only for the conservation of prey species but also for the protection of native carnivores. Concern over potential non-target mortality of quolls has hindered efforts to control foxes in eastern Australia using poison baits. We contend that, rather than harming quoll populations, baiting for foxes should aid the conservation of quolls and should be implemented in areas of sympatry where fox numbers are high. [source] Conditional Gaussian mixture modelling for dietary pattern analysisJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES A (STATISTICS IN SOCIETY), Issue 1 2007Michael T. Fahey Summary., Free-living individuals have multifaceted diets and consume foods in numerous combinations. In epidemiological studies it is desirable to characterize individual diets not only in terms of the quantity of individual dietary components but also in terms of dietary patterns. We describe the conditional Gaussian mixture model for dietary pattern analysis and show how it can be adapted to take account of important characteristics of self-reported dietary data. We illustrate this approach with an analysis of the 2000,2001 National Diet and Nutrition Survey of adults. The results strongly favoured a mixture model solution allowing clusters to vary in shape and size, over the standard approach that has been used previously to find dietary patterns. [source] Using carbon isotopes to track dietary change in modern, historical, and ancient primatesAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2009Matt Sponheimer Abstract Stable isotope analysis can be used to document dietary changes within the lifetimes of individuals and may prove useful for investigating fallback food consumption in modern, historical, and ancient primates. Feces, hair, and enamel are all suitable materials for such analysis, and each has its own benefits and limitations. Feces provide highly resolved temporal dietary data, but are generally limited to providing dietary information about modern individuals and require labor-intensive sample collection and analysis. Hair provides less well-resolved data, but has the advantage that one or a few hair strands can provide evidence of dietary change over months or years. Hair is also available in museum collections, making it possible to investigate the diets of historical specimens. Enamel provides the poorest temporal resolution of these materials, but is often preserved for millions of years, allowing examination of dietary change in deep time. We briefly discuss the use of carbon isotope data as it pertains to recent thinking about fallback food consumption in ancient hominins and suggest that we may need to rethink the functional significance of the australopith masticatory package. Am J Phys Anthropol 140:661,670, 2009. © 2009 Wiley-Liss, Inc. [source] Fallback foraging as a way of life: Using dietary toughness to compare the fallback signal among capuchins and implications for interpreting morphological variationAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2009Barth W. Wright Abstract The genus Cebus is one of the best extant models for examining the role of fallback foods in primate evolution. Cebus includes the tufted capuchins, which exhibit skeletal features for the exploitation of hard and tough foods. Paradoxically, these seemingly "specialized" taxa belong to the most ubiquitous group of closely related primates in South America, thriving in a range of different habitats. This appears to be a consequence of their ability to exploit obdurate fallback foods. Here we compare the toughness of foods exploited by two tufted capuchin species at two ecologically distinct sites; C. apella in a tropical rainforest, and C. libidinosus in a cerrado forest. We include dietary data for one untufted species (C. olivaceus) to assess the degree of difference between the tufted species. These data, along with information on skeletal morphology, are used to address whether or not a fallback foraging species exhibits a given suite of morphological and behavioral attributes, regardless of habitat. Both tufted species ingest and masticate a number of exceedingly tough plant tissues that appear to be used as fallback resources, however, C. libidinosus has the toughest diet both in terms of median and maximal values. Morphologically, C. libidinosus is intermediate in absolute symphyseal and mandibular measurements, and in measures of postcranial robusticity, but exhibits a higher intermembral index than C. apella. We propose that this incongruence between dietary toughness and skeletal morphology is the consequence of C. libidinosus' use of tools while on the ground for the exploitation of fallback foods. Am J Phys Anthropol 140:687,699, 2009. © 2009 Wiley-Liss, Inc. [source] Maternal diets, nutritional status, and zinc in contemporary Mexican infants' teeth: Implications for reconstructing paleodietsAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2009Alexis E. Dolphin Abstract Despite attempts to use zinc (Zn) concentrations in hard tissues to comment upon the degree of carnivory in past populations, zinc has yielded inconsistent trophic level effects. The question of what, if anything, zinc in human enamel reveals regarding past diets is the focus of this research. We test whether the zinc content of deciduous tooth enamel from contemporary Mexican infants varies by maternal dietary variables such as zinc intake, proportion of animal products consumed, and dietary components that are known to impact zinc absorption. Deciduous teeth were collected from former participants in a longitudinal study of maternal and infant diet and function in highland Mexico. The Zn/Ca ratios of both prenatal and postnatal regions of 37 anterior teeth representing 26 individuals were assessed via laser ablation,inductively coupled plasma,mass spectrometry. Maternal dietary data collected during lactation were not correlated with zinc levels in the early postnatal enamel of infants' teeth, which were forming at the same time. In the case of prenatal enamel, zinc values were correlated with the consumption of foods known to influence Zn bioavailability, most notably tortillas (P = 0.008; r = 0.510), but not with meat consumption. Unexpectedly, women who consumed diets with poor zinc bioavailability during pregnancy gave birth to infants whose prenatal enamel demonstrated the highest Zn/Ca ratios, possibly due to enhanced zinc absorption during pregnancy for those mothers suffering most from long-term micronutrient deficiency. These results would suggest that zinc is not a reliable trophic level indicator. Am J Phys Anthropol, 2009. © 2009 Wiley-Liss, Inc. [source] Ecological correlates of abundance in the Tana mangabey (Cercocebus galeritus)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 3 2004Julie Wieczkowski Abstract I investigated the ecological correlates of abundance in the Tana mangabey (Cercocebus galeritus), one of the world's most endangered primates, with the goal of recommending management strategies. I systematically selected 31 forest fragments throughout the mangabey's 60-km distribution along the lower Tana River in southeastern Kenya. Within the 31 fragments, I measured vegetation structure, food abundance, and human forest product use in 107 belt transects, and conducted 370 mangabey surveys. I used a weighted multiple regression analysis to determine whether there was a dependence between the selected forest attributes and the mean number of mangabey groups per fragment. Fragment area and density of trees ,10 cm diameter at breast height (DBH) were the only variables that significantly correlated with the variation in mangabey abundance. No additional variables were significant when the analysis was limited to forest fragments inside the Tana River Primate National Reserve (TRPNR) or to fragments outside the TRPNR. When I estimated the resources available before recent human forest product use by adding nonharvested and harvested variables, the total basal area of the top 15 food species became significant. This was only within the TRPNR, however. Management, therefore, should focus on increasing forest area, density of trees ,10 cm DBH, and coverage of food trees throughout the mangabey's distribution. Solutions must be found for the problem of forest clearing, and forest product use must be better managed to protect the habitat of this critically endangered primate. The significance of food abundance only within the TRPNR suggests a need to collect dietary data from mangabey groups in fragments toward the southern limit of the mangabey's distribution, where plant species composition differs from that in fragments in which dietary data have been previously collected. Am. J. Primatol. 63:125,138, 2004. © 2004 Wiley-Liss, Inc. [source] | ||||||||||