@JYoungin20years said:
@tenaka2: hahaha. theres zero evidebce for evolution. .NONE
http://myxo.css.msu.edu/ecoli/
There are some easy to read papers if you search around a little.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2430337/
This one's dandy. And I'll give you a brief summary, so you can be lazy.
The particular strain of E. coli could not use, an oxic, glucose-limited medium containing citrate, as a carbon source. Every day 1% of all 12 populations of E. coli was frozen and every 75days (~500 generations) a large sample were frozen, to preserve micro evolutionary states. Though remaining viable to unfreeze. All populations evolved larger cell volumes and lower maximum population densities.
The population Ara-3, after ~31 500 generations with every possible point mutation occurring multiple times, was the first strain of citrate using E. coli to evolve. The genomes of twenty-nine clones isolated from various time points in the Ara-3 pupulation, were sequenced to reconstruct the phylogenetic history of the population. They found that the population had diversified into three clades by 20 000 generations. Of that, the Citrate(Cit+) using variants were found in "Clade 3".
It was found that the Cit+ varients all had a duplication mutation of 2933 base pairs, involved for the citrate transporter protein used in anerobic(w/o oxygen) growth on citrate on the normally dormant citT gene. Creating a new regulatory module placing the citT gene under the control of a promoter for an adjacent gene called 'mk'.
The researchers conclude that the evolution of the Cit+ trait suggests that new traits evolve through three stages: potentiation, in which mutations accumulate over a lineage's history that make a trait accessible' actualization, in which one or more mutation render a new trait manifest; and refinement, in which the trait is improved by further mutations.
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