Secondly, a suitable method to test for adaptation, in theory and practice, might be to measure WEC in a cross-factorial design with artificial infection e.g. [ 7].
To test for adaptation, the growth rate of an evolved sub-lineage was divided by the growth rate of the fastest parental progenitor.
The asexual fitness of lineages was then measured to test for adaptation to the selective environment and trade-offs in the alternate environment.
Approximately 200 adult worms from an individual transgenic line were split into two populations; one group was exposed to S-basal buffer alone (to test for chemotaxis), while the other was pre-exposed to the AWC-sensed odor, butanone, in S-basal buffer for 80 min under otherwise identical conditions (to test for adaptation).
RifR, RifR-evolved and RifS-evolved genotypes lacking either StrR mutations or the plasmid were each assayed in three different blocks: once after the evolution experiment to test for adaptation [ 24], once alongside genotypes with K43N or K88R, and once alongside genotypes carrying the plasmid.
We tested for adaptation to LB by a paired t-test using the average fitness of each genotype before and after experimental evolution.
Finally, we used the inferred demographic model to perform an initial test for local adaptation and identified several genes, including the flowering time gene FCA and a disease resistance locus, as candidates for local adaptation events.
Finally, since the functional expression of AHP accumulation in motoneurons is spike frequency adaptation (SFA) [4], [24], we also tested for adaptation during each cycle of the scratch epochs.
Tests for adaptation (>1) or trade-offs (<1) were one-tailed, whereas tests for correlated responses in the permissive environment were two-tailed.
Within-parasite line tests for adaptation revealed no significant adaptation while within-host line tests revealed that 4 out of 10 combinations showed significant adaptation or maladaptation (Table 2).
