$24\mathrm{.}31$ Evolution in bacteria. Can bacteria evolve a preference for the pH of their environment? An evolutionary biologist took lines of Escherichia coli bacteria grown and kept at a neutral pH of $7\mathrm{.}2$ and grew them for $2000$ generations $($about $300$ days$)$ at a stressful acidic pH of $5\mathrm{.}5.$ The original bacteria $($kept frozen all that time$)$ and the $$acid$-$evolved$$ bacteria were then grown together in various test environments, and a relative fitness score was computed. A score of $1$ would indicate that both bacteria types were equally fit. A score higher than $1$ would indicate that the acid$-$evolved line was more fit than the ancestral line in that environment $($that is$,$ that the acid$-$evolved bacteria grew the most$).$ Here are the relative fitness scores obtained for test environments of pH $5\mathrm{.}5($acid$),7\mathrm{.}2($neutral$),$ or $8\mathrm{.}0($basic$).$ There are six replicates using different ancestor bacterial lines for each test environment:$15$ Test in acid pH $1\mathrm{.}241\mathrm{.}221\mathrm{.}231\mathrm{.}241\mathrm{.}181\mathrm{.}09$ Test in neutral pH $0\mathrm{.}990\mathrm{.}990\mathrm{.}980\mathrm{.}940\mathrm{.}950\mathrm{.}95$ Test in basic pH $0\mathrm{.}560\mathrm{.}830\mathrm{.}820\mathrm{.}720\mathrm{.}860\mathrm{.}84$ Do the data provide evidence that E$.$ coli can evolve adaptations to the pH of its environment over the course of $2000$ generations? Follow the four$-$step process in answering this question. $($Although the standard deviations do not quite satisfy our rule of thumb, that rule is conservative and small sample sizes can more easily lead to widely different variances. The analysis might be performed again without the low outlier to confirm the initial interpretation.$)$