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THE CARPEL. "We argue that the carpel was a key evolutionary innovation reducing accessory costs in angiosperms by allowing sporophytic control of pre- and postzygotic mate selection and timing of resource allocation. The resulting reduction in costs of aborting unfertilized ovules or genetically inferior embryos would have lowered total reproductive costs enabling early angiosperms to evolve small seed sizes and short generation times." http://onlinelibrary.wiley.com/doi/10.1111/j.1558-5646.2011.01425.x/full View in LinkedIn

MITOCHONDRIAL GENE RECOMBINATION. "On an organismal timescale, this leads to genomes consisting of a plethora of subgenomic and multimeric structures whereas on an evolutionary timescale, it results in a highly scrambled gene order between closely related species and sometimes even within a species." http://onlinelibrary.wiley.com/doi/10.1111/nph.13188/full View in LinkedIn

SEED COSTS. "Costs of abortions and packaging structures were significantly higher in gymnosperms. Also, the relationship between seed:ovule ratio and seed size was negative in angiosperms but positive in gymnosperms." http://onlinelibrary.wiley.com/doi/10.1111/j.1558-5646.2011.01425.x/full View in LinkedIn

MITOCHONDRIAL GENES. "A hallmark of angiosperm mitochondrial DNAs (mtDNAs) is their high rate of recombination and rearrangement, which is reflected in a number of unusual properties. Most angiosperm mtDNAs exhibit extraordinarily high rates of reciprocal, intra- and intermolecular recombination between large direct and inverted repeats, along with less frequent recombination across smaller repeats." https://lnkd.in/e6WHsRJ View in LinkedIn

SCALING. "It has been proposed that changes to reproductive features at the base of the angiosperm clade reduced accessory costs thus removing the fitness disadvantage of small seeds. Total accessory costs scaled isometrically to seed mass for angiosperms but less than isometrically for gymnosperms, so that smaller seeds were proportionally more expensive for gymnosperms to produce." http://onlinelibrary.wiley.com/doi/10.1111/j.1558-5646.2011.01425.x/full View in LinkedIn

TRANSPOSONS. "In angiosperms the repeat types (i.e. (retro)transposable elements, (micro)satellite DNA, and truncated derivatives) can be fast evolving in absolute copy numbers and sequence, such that in species from many plant families there are reports of repeat element half-lives of 3–4 million years near complete repeat turnover in the genome over timeframes of 5–10 million years, and repeat copy numbers changing GS two or three fold over just a few million years." (GS = genome size). http://www.sciencedirect.com/science/article/pii/S0959437X15001057 View in LinkedIn

SMALL SEEDS. "Accessory costs of reproduction frequently equal or exceed direct investment in offspring, and can limit the evolution of small offspring sizes. Early angiosperms had minimum seed sizes, an order of magnitude smaller than their contemporaries." https://lnkd.in/e6Ry-qh View in LinkedIn

TRANSPOSONS KEY. "Transposable elements (TEs) are a dominant feature of most flowering plant genomes...indicate that TEs can explain much about their rapid evolution and diversification. Genome size in angiosperms is highly correlated with TE content and the overwhelming bulk (>80%) of large genomes can be composed of TEs." (Viral fossils). https://lnkd.in/eyHApyP View in LinkedIn

"GENOME SIZE varies c. 2400-fold in angiosperms (flowering plants), although the range of genome size is skewed towards small genomes. There are two major drivers of this astonishing GS diversity: (i) polyploidy, or whole-genome duplication, causing, at least initially, step-wise increases in GS, and (ii) deviation in repeat copy numbers, that can either result in subtle or more dramatic GS changes." http://www.sciencedirect.com/science/article/pii/S0959437X15001057 View in LinkedIn

PUZZLING RANGE. "Genome sizes vary more than 2,300-fold among angiosperms, from that of Paris japonica (2n = 12, 1C = ~149 Gbp) to that of carnivorous Genlisea margaretae (2n = ~40, 1C = ~63 Mbp). The biological significance of this massive variation is puzzling." https://lnkd.in/e4xhW7h View in LinkedIn