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RAPID MICROBE EVOLUTION. "In a decade bacteria can produce 200,000 generations — about the number of generations of humans there have been since our lineage split from that of chimpanzees. So it’s hardly surprising that in less than a human lifespan we’ve seen the evolution of new diseases such as HIV and numerous antibiotic-resistant bacteria." https://www.newscientist.com/article/dn13640-evolution-myths-evolution-produces-perfectly-adapted-creatures/ View in LinkedIn

ANTIGENIC EVOLUTION. "Swine influenza A/H3N2 is known to evolve antigenically at a rate that is six times slower than that of the same virus circulating in humans, although these viruses' rates of genetic evolution are similar." https://lnkd.in/dDjCWve View in LinkedIn

HITCHHIKING. "Reassortment between segments occurs slowly enough, relative to the actions of positive selection, that genetic hitchhiking causes beneficial mutations in HA and NA to reduce diversity in linked neutral variation in other segments of the genome." https://lnkd.in/dDjCWve View in LinkedIn

BRANCH NONEPITOPE SELECTION. "Conversely, putative nonepitope sites of the HA protein evolve approximately twice as fast on side branches than on the trunk of the H3 phylogeny, indicating that mutations to these sites are selected against and viruses possessing such mutations are less likely to take over the influenza population." https://lnkd.in/dDjCWve View in LinkedIn

TRUNK EPITOPE SELECTION. "Phylogenetic analysis of H3N2 influenza has shown that putative epitope sites of the HA protein evolve approximately 3.5 times faster on the trunk of the phylogeny than on side branches. This suggests that viruses possessing mutations to these exposed sites benefit from positive selection and are more likely than viruses lacking such mutations to take over the influenza population." https://lnkd.in/dDjCWve View in LinkedIn

BRANCH SUBPOPULATION EXTINCTIONS. "Of central interest to the study of viral phylodynamics is the distinctive phylogenetic tree of epidemic influenza A/H3N2, which shows a single predominant trunk lineage that persists through time and side branches that persist for only 1–5 years before going extinct." https://lnkd.in/dDjCWve View in LinkedIn

MUTANT REFRESHERS. "After introduction into the human population, a lineage of influenza generally persists through antigenic drift, in which HA and NA continually accumulate mutations allowing viruses to infect hosts immune to earlier forms of the virus. These lineages of influenza show recurrent seasonal epidemics in temperate regions and less periodic transmission in the tropics." (HA and NA = key antigens). https://lnkd.in/dDjCWve View in LinkedIn

THE MODERN SYNTHESIS of evolutionary ideas in step with new research findings covers many revisions of past thinking. Interestingly, Mendelian inheritance is not one of these topics that have been revised, despite the fact we know of many examples of non-Mendelian inheritance, with reasonable hypotheses proposed to explain them. View in LinkedIn

FREQUENT NOVELTY. "The evolution of influenza, a segmented single-stranded RNA orthomyxovirus, is punctuated by frequent reassortment." http://www.pnas.org/content/110/46/18566.full View in LinkedIn

MOBILE GENETIC ELEMENTS, non-coding RNAs, viral origins of regulatory elements, epigenetics, Viruses, and new ways of thinking about evolution have occupied this blog for some weeks, as part of a new synthesis of molecular biology that is underway by great thinkers. Now it is time to turn to another cornerstone in modern biology that needs a review, namely Mendelian inheritance. A precondition of natural selection. View in LinkedIn