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OLD PARADIGM. “Standard Evolutionary Theory explains such parallels as convergent evolution: similar environmental conditions select for random genetic variation with equivalent results. This account requires extraordinary coincidence to explain the multiple parallel forms that evolved independently in each lake.” http://www.nature.com/news/does-evolutionary-theory-need-a-rethink-1.16080 View in LinkedIn

OLD CLONAL VIEW. “As prokaryotes, Bacteria and Archaea propagate themselves primarily by binary fission. Cell fusion and recombination are not necessary steps in their reproduction, unlike in the reproduction of complex eukaryotes. As a result, early models for understanding adaptation, evolution, and speciation in these organisms often focused on clonality and periodic selection.” https://lnkd.in/djKBnru View in LinkedIn

SWAPPING GENES. “Accumulating prokaryotic gene and genome sequences reveal that the exchange of genetic information through both homology-dependent recombination and horizontal (lateral) gene transfer (HGT) is far more important, in quantity and quality, than hitherto imagined.” https://lnkd.in/djKBnru View in LinkedIn

SPECIES BARRIERS. The next sections feature an extraordinary paper written in 2000 about the leaky species barrier, if any, in prokaryotes, a precursor to a lengthy and important paper on biological dark matter. Both papers are paradigm shifts with old thinking, heretical tomes. Both papers are unashamedly abstracted. View in LinkedIn

NON-RANDOM VARIATION. “The above insights derive from different fields, but fit together with surprising coherence. They show that variation is not random, that there is more to inheritance than genes, and that there are multiple routes to the fit between organisms and environments.” An important paper. https://lnkd.in/gninbRv View in LinkedIn

“STANDARD EVOLUTIONARY THEORY has long regarded inheritance mechanisms outside genes as special cases; human culture being the prime example. The Extended Evolutionary Synthesis explicitly recognizes that parent–offspring similarities result in part from parents reconstructing their own developmental environments for their offspring. ‘Extra-genetic inheritance’ includes the transmission of epigenetic marks (chemical changes that alter DNA expression but not the underlying sequence) that influence fertility, longevity and disease resistance across taxa.” http://www.nature.com/news/does-evolutionary-theory-need-a-rethink-1.16080 View in LinkedIn

NOISE VERSUS SIGNAL. “In essence, Standard Evolutionary Theory treats the environment as a ‘background condition’, which may trigger or modify selection, but is not itself part of the evolutionary process. It does not differentiate between how termites become adapted to mounds that they construct and, say, how organisms adapt to volcanic eruptions. We view these cases as fundamentally different.” http://www.nature.com/news/does-evolutionary-theory-need-a-rethink-1.16080 View in LinkedIn

FRAGMENT FROM NATURE continues the meditation on nature’s connectivity from a remarkable essay by Bill Graham, a former marine biologist. As a scientist, he has not only made his own observations and gathered those of others together, but has formulated some general principles about interconnectivity. I hope that you enjoy this as much as I have. View in LinkedIn

BACTERIAL RECOMBINATION EVENTS. “Because of recombination, “phylogenies of different genes from individuals of the same species should be significantly different, whereas the phylogeny of genes from individuals of different species should not be significantly different”. That is, frequent recombination should result in conflicting molecular phylogenies for genes in conspecific organisms.” https://lnkd.in/djKBnru View in LinkedIn