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CASE STUDY. “If one chooses a group of closely related bacteria (e.g., the enterobacteria) and examines phylogenies of genes shared among them, many different genes may re-create the same phylogeny of species (even though recombination can destroy congruence of gene phylogenies within species).” https://lnkd.in/djKBnru View in LinkedIn

SELECTIVE ADVANTAGES. “Of course natural selection will act as the arbiter of success for all recombinant cells. That is, the evolutionary importance of recombinatorial events will depend on the probability that the products of gene exchange offer selective advantages.” https://lnkd.in/djKBnru View in LinkedIn

RADICAL WORKAROUNDS. “The evolution of a bacteriophage-type RNA polymerase functioning in mitochondria provides an example to show that drastic replacements in the transcription machinery can occur.” https://lnkd.in/djKBnru View in LinkedIn

RAPID CHANGE. “Yet these barriers, which change at a very rapid pace, are not correlated with the degree of overall sequence divergence; and they do not preclude DNA transfer but only limit the size of transferred fragments.” https://lnkd.in/djKBnru View in LinkedIn

UNLIKELY HORIZONTAL INHERITANCE. “Similarly, lineages that adapt to an ecological niche that decreases horizontal gene transfer will become isolated from their surrounding lineages and will be recovered as deeply branching clades in most molecular phylogenies.” https://lnkd.in/djKBnru View in LinkedIn

TWO PROKARYOTIC PROCESSES. “Evolution in these contexts illustrates how both mutational and recombinatorial processes can play important roles in adaptive evolution. Homologous recombination of large fragments of DNA may also be impeded by barriers imposed by restriction endonucleases.” https://lnkd.in/djKBnru View in LinkedIn

LIKELY HORIZONTAL INHERITANCE. “Here, recognized taxonomic categories would be created exclusively through likelihood of horizontal gene transfer.” https://lnkd.in/djKBnru View in LinkedIn

NONRANDOM GENE SHARING. “If partners were chosen nonrandomly, then patterns deduced from molecular phylogenies will reflect propensities for gene transfer rather than vertical inheritance. Ironically, such preferential gene exchange could create many of the very same patterns of similarity and difference we usually attribute to vertical inheritance.” https://lnkd.in/djKBnru View in LinkedIn

KNOWING HOW TO LOOK. “If we look closely, we can sometimes glimpse evolution unfolding in real time. And often we are surprised to find ourselves directing the show.” https://lnkd.in/ghWux7x View in LinkedIn

FRAGMENT FROM NATURE picks up on a recent report that Great Tits’ beaks had lengthened in response to British bird feeding habits. And in a very short time. This story in itself is charming. But while we generally think of evolution occurring on geological time scales, there are numerous cases of evolution occurring within just tens of generations, mostly associated with human impact on ecosystems. View in LinkedIn