>>1586149>Except in environments rich in aromatic hydrocarbons (for example the human gut), the shikimic acid pathway is entirely redundant.
Studies have indicated that a good proportion (e.g. 30%) of host-associated bacteria exhibit genome reduction including incomplete shikimic acid pathway. This suggests that they sequester essential aromatic compounds from the host (e.g. gut) but (1) an incomplete pathway is not "entirely redundant", and (2) the majority of taxa in our gut appear to have a complete shikimic acid pathway. Hence shikimic acid pathway inhibition from ingested glyphosate residue will have a differential effect on our gut microbiome and therefore a "real effect" on functional diversity.
We are learning how profound the microbiome is with respect to animal health. Causing large-scale metabolic disequilibrium and shifting communities to favour taxa that are glyphosate-resistant or better adapted to "shared metabolism" with the host is obviously going to have an effect. You're dense if you think otherwise, and increasing studies are supporting this, eg:
Kittle, R. P., McDermid, K. J., Muehlstein, L., & Balazs, G. H. (2018). Effects of glyphosate herbicide on the gastrointestinal microflora of Hawaiian green turtles (Chelonia mydas) Linnaeus. Marine pollution bulletin, 127, 170-174.
Blot, N., Veillat, L., Rouzé, R., & Delatte, H. (2019). Glyphosate, but not its metabolite AMPA, alters the honeybee gut microbiota. PloS one, 14(4), e0215466.
Aitbali, Y., Ba-M'hamed, S., Elhidar, N., Nafis, A., Soraa, N., & Bennis, M. (2018). Glyphosate based-herbicide exposure affects gut microbiota, anxiety and depression-like behaviors in mice. Neurotoxicology and teratology, 67, 44-49.
Samsel, A., & Seneff, S. (2013). Glyphosate’s suppression of cytochrome P450 enzymes and amino acid biosynthesis by the gut microbiome: pathways to modern diseases. Entropy, 15(4), 1416-1463.