Gene swapping in early life forms (bacteria) created networks rather than genetic trees. The “tree of life” pattern was created only later, when Eukaryotes established the pattern of sexual reproduction. Then the concept of a species became meaningful, as groups became genetically isolated.

The Amerindian social system of overlapping tribe and clan structures is also a network, though of a different kind. Clans are internally linear by matrilinear descent, but extra-clan marriages crosslink clans among residence-based tribes. Thus every tribe contains people from all clans, but clans maintain cooperative relationships across tribes.

A person’s identity is double: it consists of blood links in clans (actually through mitochondrial DNA, though this was not known) and mate-links (or what I like to call “love-links”) in tribes. This dilutes the concept of a “nation”, just as J;>acterial genetic networks dilute the concept of a “species”. I would argue that this is beneficial, as cross-linking always is, in breaking up strict “we versus they” conflict boundaries.