a 16:0–18:1 Diether PG diet results in the synthesis of Cardiolipin with fully ether-linked hydrocarbon chains, increasing head group, but not acyl chain complexity. b A diet of both Diether PC and PG restores the headgroup, but not acyl chain, complexity of the POPC diet. c When switched from one diet to another, in this case from the D.PC diet to the POPC diet, there is an adaptation period before acyl chain scavenging occurs. d A diet derived from a total lipid extract of cells grown on the POPC diet (a “transplant” diet) restores the full complexity of the POPC. Growth on this transplanted diet was performed after the first passage (p = 1) to the new diet, before cells begin to scavenge acyl chains from exogenous phospholipids. e Reintroducing acyl chain complexity is more effective than headgroup complexity for rescuing growth (relative to cells adapted to a POPC diet), but, even when full complexity is restored, acyl chain scavenging capacity still improves growth. Error bars are mean +/− SD. * equals p-value < 0.1; ** equals p-value < 0.05; *** equals p-value < 0.01. N, number of replicates, for all growth rates was 5 or greater and can be found in Supplementary Table S2.