LIFE-HISTORY EVOLUTION AND DENSITY-DEPENDENT GROWTH IN EXPERIMENTAL POPULATIONS OF YEAST
Article first published online: 25 JUL 2012
© 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.
Volume 66, Issue 12, pages 3789–3802, December 2012
How to Cite
Jasmin, J.-N. and Zeyl, C. (2012), LIFE-HISTORY EVOLUTION AND DENSITY-DEPENDENT GROWTH IN EXPERIMENTAL POPULATIONS OF YEAST. Evolution, 66: 3789–3802. doi: 10.1111/j.1558-5646.2012.01711.x
- Issue published online: 3 DEC 2012
- Article first published online: 25 JUL 2012
- Accepted manuscript online: 11 JUN 2012 01:50PM EST
- Received February 19, 2012 Accepted May 29, 2012 Data Archived: Dryad doi:10.5061/dryad.4142d
- Correlated evolution;
- long-term selection;
- microbial experimental evolution;
- multivariate evolution;
- negative epistasis;
We studied the evolution of the correlation between growth rate r and yield K in experimental lineages of the yeast Saccharomyces cerevisiae. First, we isolated a single clone every approximately 250 generations from each of eight populations selected in a glucose-limited medium for 5000 generations at approximately 6.6 population doublings per day (20 clones per line × 8 lines) and measured its growth rate and yield in a new, galactose-limited medium (with ∼1.3 doubling per day). For most lines, r on galactose increased throughout the 5000 generations of selection on glucose whereas K on galactose declined. Next, we selected these 160 glucose-adapted clones in the galactose environment for approximately 120 generations and measured changes in r and K in galactose. In general, growth rate increased and yield declined, and clones that initially grew slowly on galactose improved more than did faster clones. We found a negative correlation between r and K among clones both within each line and across all clones. We provide evidence that this relationship is not heritable and is a negative environmental correlation rather than a genetic trade-off.