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K van Oers A W Santure I De Cauwer N EM van Bers R PMA Crooijmans B C Sheldon M E Visser J Slate M AM Groenen 《Heredity》2014,112(3):307-316
Linking variation in quantitative traits to variation in the genome is an important, but
challenging task in the study of life-history evolution. Linkage maps provide a valuable
tool for the unravelling of such trait−gene associations. Moreover, they give
insight into recombination landscapes and between-species karyotype evolution. Here we
used genotype data, generated from a 10k single-nucleotide polymorphism (SNP) chip, of
over 2000 individuals to produce high-density linkage maps of the great tit (Parus
major), a passerine bird that serves as a model species for ecological and
evolutionary questions. We created independent maps from two distinct populations: a
captive F2-cross from The Netherlands (NL) and a wild population from the United Kingdom
(UK). The two maps contained 6554 SNPs in 32 linkage groups, spanning 2010 cM and
1917 cM for the NL and UK populations, respectively, and were similar in size and
marker order. Subtle levels of heterochiasmy within and between chromosomes were
remarkably consistent between the populations, suggesting that the local departures from
sex-equal recombination rates have evolved. This key and surprising result would have been
impossible to detect if only one population was mapped. A comparison with zebra finch
Taeniopygia guttata, chicken Gallus gallus and the green anole lizard
Anolis carolinensis genomes provided further insight into the evolution of
avian karyotypes. 相似文献
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Jaime R. Alvarado Bremer James G. Ditty Jennifer S. Turner Brandon L. Saxton 《Biochemical Systematics and Ecology》2010
This study describes a multiplex PCR assay based on the 16S rRNA mitochondrial gene to identify the penaeid shrimp Farfantepenaeus aztecus, Farfantepenaeus duorarum, Farfantepenaeus brasiliensis and Litopenaeus setiferus, all native to the Gulf of Mexico, and the exotic Litopenaeus vannamei. The assay was validated using positively identified adult shrimp and confirmed by direct sequencing. Samples of postlarvae and early juveniles collected in the eastern and western Gulf of Mexico were tested yielding 119 F. aztecus, 78 F. duorarum and five L. setiferus. Reliable identification of the morphologically similar early life stages of F. aztecus and F. duorarum has important implications for management and conservation. Similarly, the ability to identify L. vannamei is relevant as early detection could help minimize the ecological impact if this species escapes to the wild. 相似文献
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To investigate whether urographic contrast media might precipitate Bence Jones protein in the renal tubules and lead to renal failure in patients with myelomatosis, the reaction between the media and myeloma urine was studied in vitro. Appreciable precipitation was found only in urine at or below pH 4·5, and its occurrence did not correlate with the type or concentration of protein present. It is concluded that the risk of urography in myelomatosis is very small. 相似文献
419.
Sarah Saxton Strassberg Nicole Creanza 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2021,376(1816)
One prominent feature of human culture is that different populations have different tools, technologies and cultural artefacts, and these unique toolkits can also differ in size and complexity. Over the past few decades, researchers in the fields of prehistoric demography and cultural evolution have addressed a number of questions regarding variation in toolkit size and complexity across prehistoric and modern populations. Several factors have been proposed as possible explanations for this variation: in particular, the mobility of a population, the resources it uses, the volatility of its environment and the number of individuals in the population. Using a variety of methods, including empirical and ethnographic research, computational models and laboratory-based experiments, researchers have found disparate results regarding each hypothesis. These discordant findings have led to debate over the factors that most significantly influence toolkit size and composition. For instance, several computational, empirical and laboratory studies of food-producing populations have found a positive correlation between the number of individuals in a population and toolkit size, whereas similar studies of hunter–gatherer populations have found little evidence of such a link. In this paper, we conduct a comprehensive review of the literature in this field of study and propose corollaries and interdisciplinary approaches with the goal of reconciling dissimilar findings into a more comprehensive view of cultural toolkit variation.This article is part of the theme issue ‘Cross-disciplinary approaches to prehistoric demography’. 相似文献
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