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EVOLUTIONARY PROFILES. "All evolved higher maximum growth rates on glucose, shorter lag phases upon transfer into fresh medium, reduced peak population densities, and larger average cell sizes relative to their ancestor. Ten populations evolved increased DNA supercoiling, and those populations examined to date show parallel changes in global gene-expression profiles." http://www.pnas.org/content/105/23/7899.full View in LinkedIn

FITNESS. "Previous analyses of this experiment have shown numerous examples of parallel phenotypic and genetic evolution. All twelve populations underwent rapid improvement in fitness that decelerated over time." http://www.pnas.org/content/105/23/7899.full View in LinkedIn

NO CITRATE USERS. "In a long-term experiment, we propagated 12 populations of E. coli, all founded from the same ancestral strain, in a medium containing glucose, which is the limiting resource, and abundant citrate. For more than 30,000 generations, none of them evolved the capacity to use the citrate, although billions of mutations occurred in each population, such that any typical base pair mutation would have been tested many times in each one." http://www.pnas.org/content/105/23/7899.full View in LinkedIn

GENETIC COMPARTMENTALIZATION. "During evolution, the genomes of eukaryotic cells have undergone major restructuring to meet the new regulatory challenges associated with compartmentalization of the genetic material in the nucleus and the organelles acquired by endosymbiosis (mitochondria and plastids)." https://lnkd.in/d7Gtrg9 View in LinkedIn

GENETIC BACKGROUND. "The founding strain is strictly asexual, and thus populations have evolved by natural selection and genetic drift acting on variation generated solely by spontaneous mutations that occurred during the experiment." http://www.pnas.org/content/105/23/7899.full View in LinkedIn

THE BIGGEST GAP. "The gap between eukaryotes and prokaryotes is recognized as the most profound evolutionary discontinuity in the living world. This gap is reflected in the fossil record." https://lnkd.in/d-J5JBr View in LinkedIn

LONG LINEAGE. "Environmental conditions have been controlled, constant, and identical for all 12 lines. To date, each population has evolved for >44,000 generations, and samples have been frozen every 500 generations, providing a rich “fossil record”." http://www.pnas.org/content/105/23/7899.full View in LinkedIn

LARGE DOWNSTREAM IMPACTS. "Although each change on an evolutionary path has some causal relation to the circumstances in which it arose, outcomes must eventually depend on the details of long chains of antecedent states, small changes in which may have enormous long-term repercussions." http://www.pnas.org/content/105/23/7899.full View in LinkedIn

TEST POPULATION. "Twelve initially identical populations of Escherichia coli were founded in 1988 to investigate this issue. They have since evolved in a glucose-limited medium that also contains citrate, which E. coli cannot use as a carbon source under oxic conditions. No population evolved the capacity to exploit citrate for >30,000 generations, although each population tested billions of mutations." http://www.pnas.org/content/105/23/7899.full View in LinkedIn

ACCIDENTS OF HISTORY. "For example, multiple beneficial mutations will arise in some unpredictable order, and those that are substituted first may differ from others in their pleiotropic effects and epistatic interactions, thus constraining some evolutionary paths while potentiating other outcomes. These accidents of history may even determine the survival or extinction of entire lineages, given the capricious and sudden nature of some environmental changes." http://www.pnas.org/content/105/23/7899.full View in LinkedIn