Just catching up with the literature and noticing that massive research effort by my @KewScience colleagues on the Plant and Fungal Tree of Life Project (PAFTOL) has revealed an Angiosperm353 tree with major differences to the Angiosperm Phylogeny Group (APG IV) tree 🧵(1/9)
For example, Solanales, Aquifoliales, Bruniales and Icacinales are polyphyletic in the new Angioserm353 tree, and a big polytomy has disappeared (2/9)
Fagales and Fabales are sister groups in the PAFTOL tree, and Oxalidales and Malpighiales are polyphyletic (3/9)
But perhaps the biggest surprise is the placement of the Magnoliids (Magnoliales, Laurales, Cenellales and Piperales) and Chloranthales by PAFTOL. These now appear to be in a clade with the Eudicots! (4/9)
Thus, the Magnoliids diverge after the Monocots in the PAFTOL tree, unlike the placement in this much-used depiction of the APG IV tree (5/9)
The authors suggest that this is due to lack of resolution in the APG IV tree and "phylogenetic conflict between nuclear & plastid genomes". "It is hardly surprising, then, that a large-scale nuclear analysis presents strongly supported, alternative relationships" (6/9)
They highlight a "conundrum": "these incongruences are visible at the ordinal backbone, but not the family level". If incongruences were due to incomplete lineage sorting and hybridization they we would expect them to be more common at lower taxonomic levels, not higher (7/9)
This is all provisional, and these are preliminary analyses of this vast project, but they could signal a big upheaval for plant taxonomy (in some ways moving back to older groupings) and challenge our current understanding of plant evolution (8/9)
I should add that the figure I tweeted is in the supplementary materials on page 17, which can be found here: datadryad.org/stash/download… (10/9)
Note that the 1000 transcriptomes project also gave a similar placement to the monocots and magnoliids & Chloranthales. See nature.com/articles/s4158… (11/9)
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Using genomic prediction to accelerate tree breeding has been pioneered by Dario Grattapaglia. Here he looks back on 12 years of progress. Initially, marker assisted breeding was overhyped...🧵(1/5) mdpi.com/1999-4907/13/1…
but now - with a far more polygenic understanding of traits and reduced cost of sequencing - genomic prediction has come of age. It "will soon become the most efficient and effective way to carry out advanced tree breeding" he argues. (2/5)
Instead of trying to find a needle in a haystack (like marker assisted breeding), genomic prediction “buys the whole haystack”. Because "the majority of, if not all, traits relevant to forest production fit Fisher’s infinitesimal model" (3/5)
A fascinating essay on the neo-Darwinian synthesis was published last month in PNAS by Nick Barton @ISTAustria, one of the foremost evolutionary biologists of our time. He reflects on some great unsolved problems in evolutionary biology... 🧵(1/n) doi.org/10.1073/pnas.2…
...and the extent to which they can be solved by the idea that biological function is spread throughout the whole genome. He argues that natural selection is most effective when it acts on "a miasma of slight variants" rather than on single genes of large effect (2/n)
This means it will be very hard to find candidate genes for many traits, and well known examples of natural selection acting on single alleles are actually atypical. It means that natural selection is most effective in cases where it is "least accessible to investigation" (3/n)