The gut microbiome, because it is transferred between generations and between individuals in social contact, can record population interactions in ways that complement the genetic record of the humans themselves.

The broader gut microbiome analysis also revealed a community distinct from modern Western gut microbiomes in ways consistent with the different diet of the Copper Age — more diverse, with different dominant species, reflecting the different foods and agricultural practices of the period.

Ötzi’s gut is, in this sense, another kind of time capsule: not just of his own biology, but of the microbial ecology of the human gut before the modern dietary and hygienic transformations that have so dramatically changed the microbiome of Western populations.

The Botanical Evidence