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Long-term (including gestational and lactational) restriction of protein (8% of diet) significantly lowered the absolute and relative consumption of 6% ethanol (EtOH) in a two-bottle, free-choice (H2O vs EtOH) situation during a 76-day test period. This difference in response between rats fed the low protein diet and those fed an isocaloric normal protein (24%) diet became non-significant in two subsequent 100-day test periods. Statistical analysis of observations on individual performance indicated that regularity, cyclicity, and duration of drinking in each animal was random over all three time intervals for both groups. The early, significantly lower EtOH consumption by the protein-restricted group may be due to a paucity of EtOH-metabolizing enzymes in brain and liver, thereby prolonging the CNS effects of lower doses of EtOH consumed. The disappearance of this difference in subsequent test periods may reflect either a behavioral or metabolic adaptation in the developing protein-deficient rat. 相似文献
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Smith CI Godsoe WK Tank S Yoder JB Pellmyr O 《Evolution; international journal of organic evolution》2008,62(10):2676-2687
Obligate pollination mutualisms--in which both plants and their pollinators are reliant upon one another for reproduction--represent some of the most remarkable coevolutionary interactions in the natural world. The intimacy and specificity of these interactions have led to the prediction that the plants and their pollinators may be prone to cospeciation driven by coevolution. Several studies have identified patterns of phylogenetic congruence that are consistent with this prediction, but it is difficult to determine the evolutionary process that underlies these patterns. Phylogenetic congruence might also be produced by extrinsic factors, such as a shared biogeographic history. We examine the biogeographic history of a putative case of codivergence in the obligate pollination mutualism between Joshua trees (Yucca brevifolia) and two sister species of pollinating yucca moths (Tegeticula spp.) We employ molecular phylogenetic methods and coalescent-based approaches, in combination with relaxed-clock estimates of absolute rates of molecular evolution, to analyze multi-locus sequence data from more than 30 populations of Y. brevifolia and its pollinators. The results indicate that the moth species diverged significantly (p < 0.01) more recently than their corresponding host populations, suggesting that the apparent codivergence is not an artifact of a shared biogeographic history. 相似文献
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Lydia K. Greene Sally L. Bornbusch Erin A. McKenney Rachel L. Harris Sarah R. Gorvetzian Anne D. Yoder Christine M. Drea 《American journal of primatology》2019,81(10-11)
Research on animal microbiomes is increasingly aimed at determining the evolutionary and ecological factors that govern host–microbiome dynamics, which are invariably intertwined and potentially synergistic. We present three empirical studies related to this topic, each of which relies on the diversity of Malagasy lemurs (representing a total of 19 species) and the comparative approach applied across scales of analysis. In Study 1, we compare gut microbial membership across 14 species in the wild to test the relative importance of host phylogeny and feeding strategy in mediating microbiome structure. Whereas host phylogeny strongly predicted community composition, the same feeding strategies shared by distant relatives did not produce convergent microbial consortia, but rather shaped microbiomes in host lineage‐specific ways, particularly in folivores. In Study 2, we compare 14 species of wild and captive folivores, frugivores, and omnivores, to highlight the importance of captive populations for advancing gut microbiome research. We show that the perturbational effect of captivity is mediated by host feeding strategy and can be mitigated, in part, by modified animal management. In Study 3, we examine various scent‐gland microbiomes across three species in the wild or captivity and show them to vary by host species, sex, body site, and a proxy of social status. These rare data provide support for the bacterial fermentation hypothesis in olfactory signal production and implicate steroid hormones as mediators of microbial community structure. We conclude by discussing the role of scale in comparative microbial studies, the links between feeding strategy and host–microbiome coadaptation, the underappreciated benefits of captive populations for advancing conservation research, and the need to consider the entirety of an animal's microbiota. Ultimately, these studies will help move the field from exploratory to hypothesis‐driven research. 相似文献
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Emily HM Wong David K Smith Raul Rabadan Malik Peiris Leo LM Poon 《BMC evolutionary biology》2010,10(1):253
Background
The influenza A virus is an important infectious cause of morbidity and mortality in humans and was responsible for 3 pandemics in the 20th century. As the replication of the influenza virus is based on its host's machinery, codon usage of its viral genes might be subject to host selection pressures, especially after interspecies transmission. A better understanding of viral evolution and host adaptive responses might help control this disease. 相似文献39.
Coevolutionary interactions between species are thought to be an important cause of evolutionary diversification. Despite this general belief, little theoretical basis exists for distinguishing between the types of interactions that promote diversification and those types that have no effect or that even restrict it. Using analytical models and simulations of phenotypic evolution across a metapopulation, we show that coevolutionary interactions promote diversification when they impose a cost of phenotype matching, as is the case for competition or host-parasite antagonism. In contrast, classical coevolutionary arms races have no tendency to promote or inhibit diversification, and mutualistic interactions actually restrict diversification. Together with the results of recent phylogenetic and ecological studies, these results suggest that the causes of diversification in many coevolutionary systems may require reassessment. 相似文献
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Lane Yoder 《PloS one》2010,5(2)