Finding. On a rich diet, it barely matters whether fruit flies meet bacteria as larvae or as brand-new adults. A few dozen to a couple hundred genes move, mostly immune genes turning on. Give microbes to adult axenic flies and almost all of that difference goes away. About ten genes do not, and that stubborn list includes mitochondrial genes, Adh, and a putative secreted neuropeptide. Timing leaves a thin metabolic scar.
Why this paper matters
Microbiome papers love critical windows. This one, on rich food, mostly falsifies a large window and then keeps a small one. Mitochondria are on the small list. That is enough to file, not enough to theorize a developmental mito-program.
What they actually measured
Two colonization times, whole-fly RNA-seq, axenic controls, adult add-back persistence.
How to read the score
Mid fifties to 60. Score 58.
What to do with it
If you study early-life microbes, repeat this on a poor diet and name the mitochondrial leftovers. Do not claim a large developmental rewiring from this brief. The directional implication is that rich-diet Drosophila buffer colonization timing except for a short metabolic/mitochondrial gene list.