Year: 2022

CONSTRAINT. "For taxa with many chromosomes, WGDs could also be detrimental if the total number of chromosomes impedes homologous chromosome recognition during meiosis following a WGD." (WGD = whole genome duplication). https://lnkd.in/bCmw3Fr View in LinkedIn

"GENOME DOWNSIZING appears to affect the average genome sizes, especially at tetraploid level, but our results emphasize the importance of constraints on genome size or monoploid number." https://lnkd.in/bCmw3Fr View in LinkedIn

OVERLOOKED. "While the role of genome downsizing following WGD is widely acknowledged, the role of genomic constraints on WGDs has received relatively little attention." (WGD = whole genome duplication). https://lnkd.in/bCmw3Fr View in LinkedIn

LIMITING TRANSPOSABLE ELEMENTS. "They concluded that some lineages might be more successful than others at reducing or preventing proliferation of transposable elements that ultimately contribute to genome size determination in cotton." https://lnkd.in/bCmw3Fr View in LinkedIn

FRAGMENT FROM NATURE continues from last weekend exploring Darwin's "abominable mystery", the rise of flowering plants (angiosperms). There was no way Darwin could have known the full story: genes had not been discovered then. Their extraordinary diversity of their sexual organs (flowers), seed design, and the genetics driving them is fascinating. I touch on a bigger topic, whole genome duplication, that will be taken up in more detail in coming weeks. View in LinkedIn

DARWIN'S EULOGY. "The more I study nature, the more I become impressed […] that the contrivances and beautiful adaptations [acquired through natural selection] transcend in an incomparable degree [those] which the most fertile imagination of the most imaginative man could suggest with unlimited time at his disposal." https://lnkd.in/eykUy37 View in LinkedIn

UNUSUAL SEX LIFE. "The morphology of angiosperm sex organs (flowers), rather than fitting those of the opposite sex, must generate a lock-and-key fit with the animals that visit them. These visitors do not normally come for sex; instead they are paid for their services, typically by means of sugary nectar or surplus pollen. Plants advertise these rewards with showy displays to assist pollinators in finding them." https://lnkd.in/e97k43F View in LinkedIn

"EXTRAFLORAL NECTARIES are nectar-secreting parts of the plant surface other than flowers. These organs are not directly involved in pollination, and can be found on virtually all aboveground plant parts. Plants bearing extrafloral nectaries are widely distributed around the world. About 114 plant families with more than 700 genera and 4000 species of plants, including pteridophytes, gymnosperms and angiosperms, are known to possess extrafloral nectaries to date." https://lnkd.in/ewhdr2N 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

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