90 research outputs found
Does hybridization between divergent progenitors drive whole-genome duplication?
This is the peer reviewed version of the following article: BUGGS, R. J. A., SOLTIS, P. S. and SOLTIS, D. E. (2009), Does hybridization between divergent progenitors drive whole-genome duplication?. Molecular Ecology, 18: 3334–3339, which has been published in final form at http://dx.doi.org/10.1111/j.1365-294X.2009.04285.x This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving
The challenge of demonstrating contemporary natural selection on polygenic quantitative traits in the wild
Reconfiguring Darwin's abominable mystery
Today, naming a mid-Cretaceous angiosperm as a modern genus is unusual and controversial. But in the current issue of Nature Plants, Shi et al.1 do just that. With evidence from multiple exquisitely preserved plant parts, they identify the modern..
The origin of Darwin's "abominable mystery".
The phrase "Darwin's abominable mystery" is frequently used with reference to a range of outstanding questions about the evolution of the plant group today known as the angiosperms. Here, I seek to more fully understand what prompted Darwin to coin the phrase in 1879, and the meaning he attached to it, by surveying the systematics, paleobotanical records, and phylogenetic hypotheses of his time. In the light of this historical research, I argue that Darwin was referring to the origin only of a subset of what are today called angiosperms: a (now obsolete) group equivalent to the "dicotyledons" of the Hooker and Bentham system. To Darwin and his contemporaries, the dicotyledons' fossil record began abruptly and with great diversity in the Cretaceous, whereas the gymnosperms and monocotyledons were thought to have fossil records dating back to the Carboniferous or beyond. Based on their morphology, the dicotyledons were widely seen by botanists in Darwin's time (unlike today) as more similar to the gymnosperms than to the monocotyledons. Thus, morphology seemed to point to gymnosperm progenitors of dicotyledons, but this hypothesis made the monocotyledons, given their (at the time) apparently longer fossil record, difficult to place. Darwin had friendly disagreements about the mystery of the dicotyledons' abrupt appearance in the fossil record with others who thought that their evolution must have been more rapid than his own gradualism would allow. But the mystery may have been made "abominable" to him because it was seen by some contemporary paleobotanists, most notably William Carruthers, the Keeper of Botany at the British Museum, as evidence for divine intervention in the history of life. Subsequent developments in plant systematics and paleobotany after 1879 meant that Darwin's letter was widely understood to be referring to the abrupt appearance of all angiosperms when it was published in 1903, a meaning that has been attached to it ever since
Changing perceptions of tree resistance research
Plants are threatened in a globalised world because people are transporting pests and pathogens around the planet at unprecedented rates. Natural resistance to pests and pathogens has never been more important. In this special issue of Plants, People, Planet we focus on resistance found in tree populations. This has long been a neglected area of research, but one that is ripe for rapid progress using genomic methods
FluentDNA: Nucleotide Visualization of Whole Genomes, Annotations, and Alignments
Researchers seldom look at naked genome assemblies: instead the attributes of DNA sequences are mediated through statistics, annotations and high level summaries. Here we present software that visualizes the bare sequences of whole genome assemblies in a zoomable interface. This can assist in detection of chromosome architecture and contamination by the naked eye through changes in color patterns, in the absence of any other annotation. When available, annotations can be visualized alongside or on top of the naked sequence. Genome alignments can also be visualized, laying two genomes side by side in an alignment and highlighting their differences at nucleotide resolution. FluentDNA gives researchers direct visualization of whole genome assemblies, annotations and alignments, for quality control, hypothesis generation, and communicating results
Molecular footprints of the Holocene retreat of dwarf birch in Britain
© 2014 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited
Polyploidy and the sexual system: what can we learn from Mercurialis annua?
The evolutionary success of polyploidy most directly requires the ability of polyploid individuals to reproduce and transmit their genes to subsequent generations. As a result, the sexual system (i.e. the mating system and the sex allocation of a species) will necessarily play a key role in determining the fate of a new polyploid lineage. The effects of the sexual system on the evolution of polyploidy are complex and interactive. They include both aspects of the genetic system, the genetic load maintained in a population and the ecological context in which selection takes place. Here, we explore these complexities and review the empirical evidence for several potentially important genetic and ecological interactions between ploidy and the sexual system in plants. We place particular emphasis on work in our laboratory on the European annual plant Mercurialis annua, which offers promising scope for detailed investigations on this topic. M. annua forms a polyploid complex that varies in its sexual system from dioecy (separate sexes) through androdioecy (males and hermaphrodites) to functional hermaphroditism. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society
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