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Lion growth was studied by fitting sex specific Von Bertalanffy curves and linear regressions to data on body mass, heart girth, shoulder height and vertebral column length. Measurements were recorded for 344 lions ( Panthera leo ) (158 ♂♂ and 186 ♀♀), from Kruger National Park, South Africa. Growth in mass for males and females was linear up to about 36 months of age 0 = 0–98 and 0–99 respectively). The other age-specific measurements were clearly curvilinear. Mean weights for adult lions (excluding stomach contents) were 187–5 kg (♂♂) and 124–2 kg (♀♀) respectively. Lions tended to continue growing up to about seven years in males and nine to 10 years in females after which they usually started to lose condition. Body mass and heart girth measurements of Kruger Park lions were compared with samples from three other populations. These showed that lions from East Africa were smaller than those from more southern populations in Rhodesia, Kalahari and Kruger Park. 相似文献
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Moving beyond the ecological functionalism of Pigs for the Ancestors, Roy Rappaport's subsequent work on ritual explored how the "obvious aspects" of ritual's formalism and the need to perform it literally embody in its performers expressions of sanctity and truth that counter the threats of lying and alternative inherent in symbolic communication. He recognized that symbolic meaning and truth presuppose social cooperation and trust between individuals, and ritual serves uniquely to reaffirm this mutuality at the level of both individual behavior and conventional meaning. Through a study of male greetings among olive baboons (Papio cynocephalus anubis), this paper illustrates how ritual in Rappaport's sense may indeed intensify cooperation in socially complex but nonlinguistic contexts by establishing a behaviorally transparent means of certifying otherwise opaque individual intentions. Thus, not only may ritual sanctify symbolic communication, but it also may have played a crucial role in its evolution, [ritual, sociocultural evolution, religion and society, symbolic communication, olive baboons, primate social behavior] 相似文献
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Gelderblom WC Abel S Smuts CM Swanevelder S Snyman SD 《Prostaglandins, leukotrienes, and essential fatty acids》1999,61(4):225-234
The mitoinhibitory effect of fumonisin B1 (FB1) on the mitogenic response of epidermal growth factor (EGF) was investigated in primary hepatocyte cultures with respect to the alterations in the omega6 fatty acid metabolic pathway. Fatty acid analyses of hepatocytes showed that EGF treatment resulted in a significant decrease in the relative levels of 20:4omega6 (arachidonic acid) and an increase in 18:2omega6 (linoleic acid). Supplementation of the hepatocyte cultures with 20:4omega6 in the absence of EGF resulted in an increase in the total omega6 and omega6/omega3 fatty acid ratio. Addition of 20:5omega3 (eicosapentaenoic acid) resulted in an increase of the relative levels of the long chain omega3 fatty acids at the expense of the omega6 fatty acids. When 20:4omega6 and 20:5omega3 was added in the presence of EGF, the mitogenic response of EGF was increased and decreased respectively. When compared to the fatty acid profiles in the absence of EGF, the decreased mitogenic response coincided with a decrease of total omega6 fatty acids and total polyunsaturated fatty acids (PUFA). In addition, the saturated and mono-unsaturated fatty acids increased and the polyunsaturated/saturated (P/S) fatty acid ratio decreased which implied a more rigid membrane structure. Addition of prostaglandin E2 (PGE2) and prostaglandin E1 (PGE1) stimulated and inhibited the mitogenic response respectively. Ibuprofen, a known cyclooxygenase inhibitor, and FB1 inhibited the EGF-induced mitogenic response in a dose-dependent manner. The mitoinhibitory effect of FB1 on the EGF response was counteracted by the addition of PGE2. FB1 also disrupts the omega6 fatty acid metabolic pathway in primary hepatocytes, resulting in the accumulation of C18:2omega6 in phospatidylcholine and triacylglicerol. The disruption of the omega6 fatty acid metabolic pathway and/or prostaglandin synthesis is likely to be an important event in the mitoinhibitory effect of FB1 on growth factor responses. 相似文献
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Gene flow and population structure of a solitary top carnivore in a human‐dominated landscape
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Jeannine S. McManus Desiré L. Dalton Antoinette Kotzé Bool Smuts Amy Dickman Jason P. Marshal Mark Keith 《Ecology and evolution》2015,5(2):335-344
While African leopard populations are considered to be continuous as demonstrated by their high genetic variation, the southernmost leopard population exists in the Eastern and Western Cape, South Africa, where anthropogenic activities may be affecting this population's structure. Little is known about the elusive, last free‐roaming top predator in the region and this study is the first to report on leopard population structuring using nuclear DNA. By analyzing 14 microsatellite markers from 40 leopard tissue samples, we aimed to understand the populations' structure, genetic distance, and gene flow (Nm). Our results, based on spatially explicit analysis with Bayesian methods, indicate that leopards in the region exist in a fragmented population structure with lower than expected genetic diversity. Three population groups were identified, between which low to moderate levels of gene flow were observed (Nm 0.5 to 3.6). One subpopulation exhibited low genetic differentiation, suggesting a continuous population structure, while the remaining two appear to be less connected, with low emigration and immigration between these populations. Therefore, genetic barriers are present between the subpopulations, and while leopards in the study region may function as a metapopulation, anthropogenic activities threaten to decrease habitat and movement further. Our results indicate that the leopard population may become isolated within a few generations and suggest that management actions should aim to increase habitat connectivity and reduce human–carnivore conflict. Understanding genetic diversity and connectivity of populations has important conservation implications that can highlight management of priority populations to reverse the effects of human‐caused extinctions. 相似文献
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Nathan Wiggers Sandra L. P. Nauwelaerts Sarah Jane Hobbs Sophie Bool Claudia F. Wolschrijn Willem Back 《PloS one》2015,10(2)
Left-right symmetrical distal limb conformation can be an important prerequisite for a successful performance, and it is often hypothesized that asymmetric or uneven feet are important enhancing factors for the development of lameness. On a population level, it has been demonstrated that uneven footed horses are retiring earlier from elite level competition, but the biomechanical consequences are not yet known. The objectives of this study were to compare the functional locomotor asymmetries of horses with uneven to those with even feet.Hoof kinetics and distal limb kinematics were collected from horses (n = 34) at trot. Dorsal hoof wall angle was used to classify horses as even or uneven (<1.5 and >1.5° difference between forefeet respectively) and individual feet as flat (<50°), medium (between 50° and 55°) or upright (>55°). Functional kinetic parameters were compared between even and uneven forefeet using MANOVA followed by ANOVA. The relative influences of differences in hoof angle between the forefeet and of absolute hoof angle on functional parameters were analysed using multiple regression analysis (P<0.05).In horses with uneven feet, the side with the flatter foot showed a significantly larger maximal horizontal braking and vertical ground reaction force, a larger vertical fetlock displacement and a suppler fetlock spring. The foot with a steeper hoof angle was linearly correlated with an earlier braking-propulsion transition. The conformational differences between both forefeet were more important for loading characteristics than the individual foot conformation of each individual horse. The differences in vertical force and braking force between uneven forefeet could imply either an asymmetrical loading pattern without a pathological component or a subclinical lameness as a result of a pathological development in the steeper foot. 相似文献
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H.Y. Tichelaar P.J. van Jaarsveld C.M. Smuts M. Marais M.C. Mdhluli M. Kruger A.J.S. Benad 《Journal of medical primatology》1998,27(5):240-243
Nonhuman primates are of interest as models of human physiology to study the effect of multiple pregnancies on birth weight. Reference plasma and red blood cell (RBC) total phospholipids fatty acids were established in nonpregnant breeding female Vervet monkeys. Twenty-three clinically healthy nonpregnant Vervet monkeys (Cercopithecus aethiops), contained in a controlled closed environment and consuming a high carbohydrate diet (68 E%) that contained 20 E% fat and 12 E% protein were sampled for blood during a cross-sectional study. A low intake of ω3 fatty acids was reflected by a high ω6/ω3 ratio (66:1) of the diet. Inverse relations were seen between plasma and RBC total phospholipid fatty acids, 18:2ω6, 20:3ω6, and 20:4ω6, which suggested selective incorporation in membranes. Low levels of 20:5ω3 and 22:6ω3 of plasma and RBC total phospholipids render Vervet monkeys as ideal subjects to study the effect of ω3 fatty acid supplementation on pregnancy outcomes. Tichelaar HY, van Jaarsveld PJ, Smuts CM, Marais M, Mdhluli MC, Kruger M, Benadé AJS. Plasma and red blood cell total phospholipid fatty acid status of nonpregnant female Vervet monkeys (Cercopithecus aethiops) on a high carbohydrate maintenance diet. J Med Primatol 1998; 27:240–243. © Munksgaard, Copenhagen 相似文献
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Venuprasad R Bool ME Quiatchon L Atlin GN 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(2):323-332
A large-effect QTL associated with grain yield in aerobic environments was identified in three genetic backgrounds, Apo/2*Swarna, Apo/2*IR72, and Vandana/2*IR72, using bulk-segregant analysis (BSA). Apo and Vandana are drought-tolerant aerobic-adapted varieties, while Swarna and
IR72 are important lowland rice varieties grown on millions of hectares in Asia but perform poorly in aerobic conditions.
Two closely linked rice microsatellite (RM) markers, RM510 and RM19367, located on chromosome 6, were found to be associated
with yield under aerobic soil conditions in all three backgrounds. The QTL linked to this marker, qDTY6.1 (DTY, grain yield under drought), was mapped to a 2.2 cM region between RM19367 and RM3805 at a peak LOD score of 32 in the
Apo/2*Swarna population. The effect of qDTY6.1 was tested in a total of 20 hydrological environments over a period of five seasons and in five populations in the three
genetic backgrounds. In the Apo/2*Swarna population, qDTY6.1 had a large effect on grain yield under favorable aerobic (R
2 ≤ 66%) and irrigated lowland (R
2 < 39%) conditions but not under drought stress; Apo contributed the favorable allele in all the conditions where an effect
was observed. In the Apo/IR72 cross, Apo contributed the favorable allele in almost all the aerobic environments in RIL and
BC1-derived populations. In the Vandana/IR72 RIL and BC1-derived populations, qDTY6.1 had a strong effect on yield in aerobic drought stress, aerobic non-stress, and irrigated lowland conditions; the Vandana
allele was favorable in aerobic environments and the IR72 allele was favorable in irrigated lowland environments. We conclude
that qDTY6.1 is a large-effect QTL for rice grain yield under aerobic environments and could potentially be used in molecular breeding
of rice for aerobic environments. 相似文献
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Marinka van der Hoeven Jennifer Osei Minrie Greeff Annamarie Kruger Mieke Faber Cornelius M Smuts 《Journal of ethnobiology and ethnomedicine》2013,9(1):78