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381.
R García-Robles L Ruilope E Manche?o A Hurtado J M Alcázar C Varela H de la Calle J L Rodicio J Sancho 《Revista Espanola de Fisiología》1984,40(1):63-68
The influence of an increased endogenous production of angiotensin II and of sodium homeostasis upon the response of plasma aldosterone to metoclopramide administration has been investigated in 5 normal volunteers. Our results show that the increase of plasma aldosterone after metoclopramide administration is independent of angiotensin II, ACTH and potassium, and that it increases even further due to the endogenous production of angiotensin II induced by postural changes. The state of sodium balance seems to influence the response of plasma aldosterone to metoclopramide administration as it occurs with other stimuli of aldosterone secretion. 相似文献
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A. Magdalena Hurtado Kim Hill Ines Hurtado Hillard Kaplan 《Human nature (Hawthorne, N.Y.)》1992,3(3):185-216
Even though female food acquisition is an area of considerable interest in hunter-gatherer research, the ecological determinants
of women’s economic decisions in these populations are still poorly understood. The literature on female foraging behavior
indicates that there is considerable variation within and across foraging societies in the amount of time that women spend
foraging and in the amount and types of food that they acquire. It is possible that this heterogeneity reflects variation
in the trade-offs between time spent in food acquisition and child care activities that women face in different groups of
hunter-gatherers. In this paper we discuss the fitness trade-offs between food acquisition and child care that Hiwi and Ache
women foragers might face. Multiple regression analyses show that in both populations the daily food acquisition of a woman’s
spouse is negatively related to female foraging effort. In addition, nursing mothers spend less time foraging and acquire
less food than do nonnursing women. As the number of dependents that a woman has increases, however, women also increase foraging
time and the amount of food they acquire. Some interesting exceptions to these general trends are as follows: (a) differences in foraging effort between nursing and nonnursing women are less pronounced when fruits and roots are in season
than in other seasons of the year; (b) foraging return rates decrease for Ache women as their numbers of dependents increase; and (c) among Ache women, the positive effect of number of dependents on foraging behavior is less pronounced when fruits are in
season than at other times of the year. Lastly, in the Hiwi sample we found that postreproductive women work considerably
harder than women of reproductive age in the root season but not in other seasons of the year. We discuss how ecological variation
in constraints, the number of health insults to children that Hiwi and Ache mothers can avoid, and the fitness benefits they
can gain from spending time in food acquisition and child care might account for differences and similarities in the foraging
behaviors of subgroups of Hiwi and Ache mothers across different seasons of the year. Valid tests of the explanations we propose
will require considerable effort to measure the relationship between maternal food acquisition, child care, and adverse health
outcomes in offspring.
This paper is dedicated to Nutsiya, the hardest-working grandmother we ever observed
Kristen Hawkes contributed useful information on female foraging among the Hadza. The research was funded by the National
Science Foundation (BNS-8613215, BNS-538228, BNS-8309834, BNS-8121209) and the L. S. B. Leakey Foundation. The senior author
was supported by fellowships from the Fundacion Gran Mariscal de Ayacucho of Venezuela and the National Institute of Health
(Grant No. 1 RO1 HD16221-01A2).
A. Magdalena Hurtado, Kim Hill, and Hillard Kaplan collaborate in research on the evolutionary ecology of the division of
labor by sex. Ines Hurtado is Senior Research Scientist at the Instituto Venezolano de Investigaciones Científicas, Venezuela.
She studies the immunology of parasite load and atopic illness in Hiwi foragers. 相似文献
385.
Juan Hurtado Eduardo M. Soto Liliana Orellana Esteban Hasson 《Evolutionary ecology》2012,26(3):733-743
Drosophila buzzatii and D. koepferae coexist in the arid lands of southern South America and exploit different types of cactus as breeding hosts. The former prefers
to lay eggs on the rotting pads of prickly pears (genus Opuntia) whereas D. koepferae exhibits greater acceptance for columnar cacti (e.g., Echinopsis terschekii). Here, we demonstrate that the rearing cacti affect male mating success, flies reared in each species’ preferred host exhibited
enhanced mating success than those raised in secondary hosts. Opuntia sulphurea medium endows D. buzzatii males with greater mating ability while D. koepferae males perform better when flies develop in Echinopsis terschekii. These effects are not mediated through body size, even in D. buzzatii whose body size happens to be affected by the rearing cacti. This scenario, which is consistent with the evolution of host
specialization and speciation through sensory drive, emphasizes the importance of habitat isolation in the coexistence of
these cactophilic Drosophila. 相似文献
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This research explores male reproductive parameters, particularly the timing of first reproduction, in two traditional populations. Predictions are drawn from theoretical arguments that have their roots in evolutionary psychology and behavioral ecology, and that interpret variation in reproductive outcomes as environmentally contingent adaptations. In both Ache and Mayan samples, father absence, predicted to act as a stressor that causes precocious sexuality and reproduction as well as unstable pair bonds, did not affect the timing of first reproduction in male offspring in the expected way. Father absence in Mayan men, however, was found to be associated with responses to questionnaire items indicating lack of willingness to pay time and energy costs to maintain existing sexual unions. The results suggest that father absence affects male mating strategy, but that strategic differences did not translate into reproductive outcomes in the sample. In the Mayan population, education was associated with early reproduction, more lifetime sex partners, and higher fertility, which was also contrary to the predicted pattern based on a life-history tradeoff approach. Parental resources were associated with earlier reproduction in the Mayan sample, confirming the prediction that restricted resources should delay reproduction. 相似文献
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