Long-Term Experimental Evolution in Escherichia Coli. VI. Environmental Constraints on Adaptation and Divergence
AUTOR(ES)
Travisano, M.
RESUMO
The effect of environment on adaptation and divergence was examined in two sets of populations of Escherichia coli selected for 1000 generations in either maltose- or glucose-limited media. Twelve replicate populations selected in maltose-limited medium improved in fitness in the selected environment, by an average of 22.5%. Statistically significant among-population genetic variation for fitness was observed during the course of the propagation, but this variation was small relative to the fitness improvement. Mean fitness in a novel nutrient environment, glucose-limited medium, improved to the same extent as in the selected environment, with no statistically significant among-population genetic variation. In contrast, 12 replicate populations previously selected for 1000 generations in glucose-limited medium showed no improvement, as a group, in fitness in maltose-limited medium and substantial genetic variation. This asymmetric pattern of correlated responses suggests that small changes in the environment can have profound effects on adaptation and divergence.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1207989Documentos Relacionados
- Long-Term Experimental Evolution in Escherichia Coli. IV. Targets of Selection and the Specificity of Adaptation
- Long-term experimental evolution in Escherichia coli. X. Quantifying the fundamental and realized niche
- Long-term experimental evolution in Escherichia coli. XI. Rejection of non-transitive interactions as cause of declining rate of adaptation
- Long-term Hazards from Environmental Chemicals
- Long-term potentiation and long-term depression: a clinical perspective