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LOSSES OFFSET BY MASSIVE GAINS. "In the long term, excess of gene losses obviously would lead to genome degradation and eventually extinction, and indeed such is the fate of many groups of microbes, in particular parasites and symbionts. In general, however, the gradual gene loss appears to be offset by episodic, massive gene gain that might accompany the emergence of major groups of prokaryotes." https://lnkd.in/dSemZpD View in LinkedIn

LOSSES BEAT MUTATIONS. "Strikingly, the most common process of genome dynamics is actually loss of genes: for most (although not all) groups of microbes, evolutionary reconstructions indicate a twofold to threefold excess of losses over gains per nucleotide substitution." https://lnkd.in/dSemZpD View in LinkedIn

SEVERAL EVENTS. "Although the rates of gene gain, loss, and duplication greatly differ across the bacterial diversity, in the most dynamic groups, several gene gains and losses occur during the time the genome accumulates, on average, one nucleotide substitution per gene." https://lnkd.in/dSemZpD View in LinkedIn

HEATED DEBATE. "A computational pipeline that automatically produced a comprehensive ‘Tree of Life’ (TOL) from a concatenated sequence alignment of universal proteins was hailed as a major advance of phylogenomics, only to be immediately debunked as a “tree of 1%”, i.e. one that (at best) accurately reflects the evolutionary history of only a small fraction of microbial genes." https://lnkd.in/dSemZpD View in LinkedIn

HGT AS EVOLVABLE. "Given the indispensability of HGT for the survival of microbial populations, a plausible hypothesis seems to be that HGT is evolvable, i.e. is an adaptive, selectable trait." (HGT = horizontal gene transfer). https://lnkd.in/dSemZpD View in LinkedIn

TREE THINKING DEBATE. "The concept of ‘lateral genomics’...posits that the dominant process in microbial evolution is gene exchange between organisms rather than vertical descent along a tree. In its extreme form, lateral genomics denies the relevance of tree-like evolution and “tree thinking” in biology altogether." https://lnkd.in/dSemZpD View in LinkedIn

ENZYMATIC FITNESS. "As the network grows, gain of a single enzyme is increasingly likely to provide access to a new nutrient leading to increased fitness." https://lnkd.in/dSemZpD View in LinkedIn

CURIOUS PARADOX. "Similar analyses appear to indicate that, in addition to donating hundreds of genes to the emerging eukaryotic lineage, mitochondrial endosymbiosis severely curtailed HGT." (HGT = horizontal gene transfer). https://lnkd.in/dSemZpD View in LinkedIn

METABOLIC INNOVATION. "Escape from Muller’s ratchet can be considered the most fundamental benefit of HGT in microbial evolution but it certainly is not the only one. Acquisition of new genes and whole operons appears to be the principal route of metabolic network expansion in microbes." (HGT = horizontal gene transfer). https://lnkd.in/dSemZpD View in LinkedIn

MAJOR TRANSITIONS. "Recent phylogenomic analyses suggest that episodes of massive HGT were pivotal for the emergence of major groups of organisms such as multiple archaeal phyla as well as eukaryotes." (HGT = horizontal gene transfer). https://lnkd.in/dSemZpD View in LinkedIn