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THIS IS NOT THE PLACE to go into a detailed discussion of GMOs. I have used them to illustrate the practical considerations of horizontal gene transfer, along with antibiotic resistance. Remember the Saxon King Cnut (995-1035) who tested his powers in the East Anglian Wash by commanding the tide not to rise? https://lnkd.in/eMbpfsJ View in LinkedIn

SOIL RESISTANCE POOL. "The reuse of treated wastewater (TWW) for irrigation is a practical solution for overcoming water scarcity, especially in arid and semiarid regions of the world. One such risk stems from the fact that TWW irrigation may increase antibiotic resistance (AR) levels in soil bacteria, potentially contributing to the global propagation of clinical AR." https://lnkd.in/e2B99ZZ View in LinkedIn

SO ENDS this first weekend on reductive evolution. It is becoming clear that evolution has extended periods of gene streamlining and loss interspersed by periods of vigorous gene amplification and innovation as new life forms develop. And among those species who adopt a parasitic or symbiotic lifestyle, there can be massive gene loss. This is contrary to the simple paradigm of life inexorably becoming more complex with time. View in LinkedIn

VIRAL REDUCTIVE EVOLUTION. "The interesting thing about these results is that they indicate that viruses must have diversified from ancient cells by a process called reductive evolution, where organisms simplify instead of becoming more complex." http://www.popsci.com/new-evidence-that-viruses-are-alive View in LinkedIn

MUTATION AND REDUCTION. "There appears to be a negative correlation between mutation rate and genome size among RNA viruses." High is correlated with small. https://lnkd.in/eJEAMe9 View in LinkedIn

RARER DIRECTIONAL EVOLUTION. "Previous analyses of evolutionary patterns, or modes, in fossil lineages have focused overwhelmingly on three simple models: stasis, random walks, and directional evolution. Our expanded survey is consistent with its predecessors in finding that stasis and random walk modes are prevalent in paleontological sequences, and in suggesting that sustained directional evolution is infrequently observed." https://lnkd.in/emAzRkZ View in LinkedIn

REDUCED FUNCTION. "Regardless of the cause of genome reduction, lost coding potential eventually dictates loss of function. Consequences of reductive evolution in streamlined organisms include atypical patterns of prototrophy and the absence of common regulatory systems, which have been linked to difficulty in culturing these cells." https://lnkd.in/ebFkv5a View in LinkedIn

DOMINANT GENOME REDUCTION. "The results of evolutionary reconstructions for highly diverse organisms and through a wide range of phylogenetic depths indicate that contrary to widespread and perhaps intuitively plausible opinion, genome reduction is a dominant mode of evolution that is more common than genome complexification, at least with respect to the time allotted to these two evolutionary regimes." https://lnkd.in/egqWFZp View in LinkedIn

ABUNDANT STREAMLINING. "Bona fide adaptive genome streamlining appears to be a reality of evolution as well. Features of such streamlining are detectable in the genomes of the highly successful free-living organisms...(including) the most abundant cellular life forms on earth. Genome evolution of these highly successful life forms involves a drop in the overall complexity but an increase in information density." https://lnkd.in/egqWFZp View in LinkedIn

TWO REDUCTION ROUTES. "Both neutral and adaptive routes lead to genome reduction. Genome reduction in different life forms seems to have occurred via two distinct routes: (i) the neutral gene loss ratchet and (ii) adaptive genome streamlining." https://lnkd.in/egqWFZp View in LinkedIn