r and K Selection in Experimental Populations of Escherichia coli

  title={r and K Selection in Experimental Populations of Escherichia coli},
  author={Leo S. Luckinbill},
  pages={1201 - 1203}
Populations were adapted in vitro under density-dependent and density-independent population controls. Comparison of strains fails to demonstrate any trade-off in adaptation under these population controls. 
An Experimental Analysis of a Life History Theory
E. coli appears to have hedged its environmental bets by the capacity for either rapid growth and exploitation, or persistence in the face of depleted resources, as the situation demands. Expand
Evolution of carrying capacity in evolution experiments focusing on a single locus on the Escherichia coli chromosome
This work constructed random mutant populations of Escherichia coli in which members differed only in part of the genomic copy of the glutamine synthetase gene and performed daily serial transfer culture where the populations were in K-selected environments. Expand
Evolutionary Changes of Ecological Traits of Bacterial Populations through Predator-Mediated Competition 1. Experimental Analysis
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Evolution of a bacteria/plasmid association
The fitness of each combination of host and plasmid, with and without the culture history, was determined by competing it against a baseline strain, and results indicate adaptation by the host genome, but no plasmids adaptation. Expand
Comparison of the Density-Dependent Population Process between Laboratory and Wild Strains of Callosobruchus Chinensis (L.)
The reproduction curves were determined for 6 strains of the azuki bean weevil, Callosobruchus chinensis. Various numbers of adult pairs from stocks were introduced into petri dishes with a constantExpand
Long-Term Experimental Evolution in Escherichia coli. II. Changes in Life-History Traits During Adaptation to a Seasonal Environment
The independently derived genotypes are somewhat more variable in these life-history traits than in their relative fitnesses, which indicates that they acquired different genetic adaptations to the seasonal environment. Expand
r- and K-selection in experimental populations of vesicular stomatitis virus.
  • A. V. Bordería, S. Elena
  • Biology, Medicine
  • Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases
  • 2002
The adaptation of vesicular stomatitis RNA virus to different population densities and the existence of a trade-off between r- and K-selection are explored and the results support the exist of the expected trade-offs between these two types of selections. Expand
Changes in Dispersiveness of Bacterial Populations in Long-Term Serial Transfer Cultures
Results suggest that competition in bacterial populations may be alleviated by the enhanced dispersiveness of highly competitive cells from densely populated areas. Expand
In mixed culture, serial transfer at 3—d intervals led to coexistence of the two species, and resulted in the r values of both species undergoing slight reductions or remaining unchanged in comparison to the parental strain. Expand
The unconstrained evolution of fast and efficient antibiotic-resistant bacterial genomes
It is unsurprising for r-adaptation in the presence of a ribosome-inhibiting antibiotic, doxycycline, to also increase population size, and two costs are found: an elongated lag phase and the loss of stress protection genes. Expand


Nuclear segregation and the growth of clones of spontaneous mutants of bacteria.
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r- and K-Selection in Typha
Properties of population samples of three species of Typha conformed to the theory that r-selected genotypes have a greater developmental speed and higher fecundity and there is a selective trade-off between mechanisms contributing to colonization potential and those contributing to competitive potential. Expand
Reproductive strategies of dewberries
In a stable, predictable habitat when popula- tion density is low and clonal expansion is possible, vegetative reproduction should be favored, but in a temporally unstable habitat, this reproductive density response will not exist. Expand
r and K Selection or b and d Selection?
It is hypothesized that maximal tolerable niche overlap should vary inversely with the level of competition, and a test is suggested. Expand
Environmental Certainty, Trophic Level, and Resource Availability in Life History Evolution
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Parasitism and Distributional Gaps between Allopatric Species
The models adequately describe nature, but it is argued that the authors now know too little about nature to conclude that they do not, and the central question in the evolution of reproductive mode remains: is juvenile production or juvenile survival to maturity the driving force. Expand
The Detection of Regulation in Animal Populations
If the detection of regulation in a population is attempted by taking a linear regression of log population density against log previous population density, the slope, b, of the line thus obtained isExpand
Ecology and Physiological Aspects of Reproductive Strategies in Two Lizards
Two lizard species, the northern prairie lizard from Reno County, Kansas and the northern sagebrush lizard from Washington County, Utah, were used to test four hypotheses and one assumption related to the theory of r— and K—selection. Expand
Regulation is defined as the return of a population to equilibrium density. An operational definition of regulation is convergence to a single density by subpopulations which have been manipulatedExpand