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Longevity is a major characteristic of animals that has long fascinated scientists. In this work, we present a comprehensive database of animal longevity records and related life‐history traits entitled AnAge, which we compiled and manually curated from an extensive literature. AnAge started as a collection of longevity records, but has since been expanded to include quantitative data for numerous other life‐history traits, including body masses at different developmental stages, reproductive data such as age at sexual maturity and measurements of reproductive output, and physiological traits related to metabolism. AnAge features over 4000 vertebrate species and is a central resource for applying the comparative method to studies of longevity and life‐history evolution across the tree of life. Moreover, by providing a reference value for longevity and other life‐history traits, AnAge can prove valuable to a broad range of biologists working in evolutionary biology, ecology, zoology, physiology and conservation biology. AnAge is freely available online ( http://genomics.senescence.info/species/ ). 相似文献
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We compared nucleotide sequences of exon 4 and part of exon 5 of alleles F and S of the Adh1 locus controlling alcohol dehydrogenase in sugar beet. The Adh1-F and Adh1-S sequences of the examined fragment were shown to differ by two nucleotides. Adenine (A) and cytosine (C) of Adh1-F were substituted by respectively thymine (T) and adenine (A) in Adh1-S. Consequently, glutamine and asparagine from the F subunit of ADH1 are replaced by valine and lysine, respectively. Because of differences in the amino acid content, the F subunit is by two elementary charges more negatively charged electrically than the S subunit, which correlates with differences in their electrophoretic mobility. Comparison of the examined Adh1 fragment of sugar beet with its counterparts in other plants showed that the sites bearing substitutions in the former species are classed as variable. 相似文献
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MATEUS R. ANDRADE DANIEL ALBENY‐SIMÕES JENNIFER A. BREAUX STEVEN A. JULIANO ERALDO LIMA 《Ecological Entomology》2017,42(1):77-85
1. Prey organisms can perceive cues to predation hazard and adopt low‐risk behaviours to increase survival. Animals with complex life cycles, such as insects, can exhibit such anti‐predatory behaviours in multiple life stages. 2. Cues to predation risk may induce ovipositing females to choose habitats with low predation risk. Cues to predation risk may also induce larvae to adopt facultative behaviours that reduce risk of predation. 3. One hypothesis postulates that anti‐predation behaviours across adult and larval stages may be negatively associated because selection for effective anti‐predator behaviour in one stage leads to reduced selection for avoidance of predators in other stages. An alternative hypothesis suggests that selection by predation favours multi‐component defences, with both avoidance of oviposition and facultative adoption of low‐risk behaviours by larvae. 4. Laboratory and field experiments were used to determine whether defensive responses of adult and larval mosquitoes are positively or negatively associated. The study tested effects of waterborne cues from predatory Toxorhynchites theobaldi on oviposition choices and larval behaviours of three of its common prey: Culex mollis, Limatus durhamii and Aedes albopictus. 5. Culex mollis shows strong anti‐predator responses in both life stages, consistent with the hypothesis of a multi‐component behavioural defence. The other two species showed no detectable responses to waterborne predator cues in either adult or larval stages. Larvae of these unresponsive species were significantly more vulnerable to this predator than was C. mollis. 6. For these mosquitoes, species appear either to have been selected for multi‐component defences against predation or to act in ways that could be called predator‐naïve. 相似文献
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Summer distribution of Red-legged Partridges Alectoris rufa in relation to water availability on Mediterranean farmland 总被引:1,自引:0,他引:1
The suggestion that the summer distribution of Red-legged Partridges Alectoris rufa in the Mediterranean region is determined by the availability of surface water was examined on the agricultural farm, Alto Alentejo, southern Portugal. Partridge coveys were surveyed between 15 July and 15 August in 1993 and 1994. Using a vector-based Geographic Information System, we assessed, for each covey location and for the locations of a double number of random points, the distance to the nearest water point, distance to field boundaries, distance to water lines and land use classes. Univariate comparisons were made between the two groups of locations, and three multivariate logistic models were fitted through forward stepwise selection to the 1993, 1994 and pooled data sets to estimate the probability of sighting partridge coveys in the study area. Distance to water was significantly lower for partridge locations than for random points in both years and was the only variable selected for all logistic models. Apart from water availability, Red-legged Partridge locations were also affected by land use and distance to field boundaries. 相似文献
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Knowledge on interspecific pre‐ and post‐zygotic isolation mechanisms provides insights into speciation patterns. Using crosses (F1 and backcrosses) of two closely related flea beetles species, Altica fragariae and A. viridicyanea, specialized on different hosts in sympatry, we measured: (a) the type of reproductive isolation and (b) the inheritance mode of preference and host‐specific performance, using a joint‐scaling test. Each species preferred almost exclusively its host plant, creating strong prezygotic isolation between them, and suggesting that speciation may occur at least partly in sympatry. Reproductive isolation was intrinsic between females of A. fragariae and either A. viridicyanea or F1 males, whereas the other crosses showed ecologically dependent reproductive isolation, suggesting ecological speciation. The genetic basis of preference and performance was at least partially independent, and several loci coded for preference, which limits the possibility of sympatric speciation. Hence, both ecological and intrinsic factors may contribute to speciation between these species. 相似文献
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Health Is not always written in bone: Using a modern comorbidity index to assess disease load in paleopathology 下载免费PDF全文
Katherine van Schaik Dmitry Vinichenko Frank Rühli 《American journal of physical anthropology》2014,154(2):215-221
Paleopathology has revealed much about disease in the past but is usually limited to conditions with osteological manifestations; this often excludes acute soft tissue infections and causes of death for most individuals in the past and present. Our understanding of the evolution of disease is essential for contextualizing and predicting the epidemiological shifts that are happening in modern society, as high rates of infectious disease coexist alongside high rates of chronic disease in rates unlike those observed previously in human history. Moreover, many physiological states not previously classified as “disease” (obesity) have become pathologized, influencing our conception of disease and what defines health. By using the Galler Collection, a pre‐antibiotic and pre‐chemotherapeutic osteological series with modern autopsy records, our research quantifies disease burden of the past using the Charlson Index (CI), a modern comorbidity index of disease severity. Galler Collection remains and autopsy records were scored with the Charlson Index to correlate bone findings with soft tissue findings, and statistical analysis was performed for cumulative scores and absolute diagnosis counts, with patients stratified by sex and cause of death (pneumonia or cancer). Osteological diagnosis counts were more predictive of soft‐tissue autopsy disease counts than were associated cumulative CI scores. Diagnosis counts and CI scores for osteological data were more closely related to associated soft tissue data for cancer patients than for pneumonia patients. This research indicates how interdisciplinary paleopathological analysis assists in making more reliable assessments of health and mortality in the past, with implications for trending and predicting future epidemiological shifts. Am J Phys Anthropol 154:215–221, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
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ANDRÉ O. SIMÕES † MARÍLIA DE M. CASTRO LUIZA S. KINOSHITA 《Botanical journal of the Linnean Society. Linnean Society of London》2006,152(3):387-398
The structure and organization of calycine colleters belonging to four genera of Apocynaceae are described. Calycine colleters were found in all species. All colleters had the same histological composition, but morphological differences were observed in four species. Most colleters were of the standard type, and possible deviations resulted in three morphological types: bifurcated, laminar, and sessile. Mechanisms of cell separation, proliferation, and elongation may explain the origin of the new types. As a consequence of morphological changes, the secretory surface was expanded in the bifurcated, laminar, and sessile glands. Most colleters were in a post-secretory phase, but a hydrophilic secretion was observed in Mandevilla pycnantha and Mesechites mansoana . A larger secretory surface, together with the extension of the secretory phase in adult flowers, were major shifts in the calycine colleters of Apocynaceae, and are possibly correlated with the functional and ecological aspects of these organs. Three patterns of distribution of calycine colleters were observed: alternate, opposite, or indefinitely distributed. The alternate pattern was not homogeneous, and three subtypes were recognized: four-, five-, and ten-grouped colleters. The number of calycine colleters was variable between taxa and even within the same species. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 387–398. 相似文献