Individuation – the genesis of individual entities – is generally presumed to begin with the ontology of already constituted individuals. Rather than describing the appearance of individual beings from something pre-individual, the analysis of the appearance of concrete entities usually concerns itself with the appearance of composites, in which ontological privilege is given to the already constituted individuals. Is this the case with Umwelt theory as well? A straightforward conception of umwelts would treat them as a composites of organism and environment, and the emphasis is then on their mutual co-constitution through functional cycles. This already presumes the pre-constitution of both environments and organisms. But then what is the origin and genesis of organisms and environments which are now, as if after the fact, to be indivisibly united once again? With the help of a certain resonance between the concepts of transaction, individuation and schismogenesis, the presentation proposes that rather than organisms and environments, it is the umwelt which is ontologically primary, and that it is the internal division, separation and individuation within umwelts which gives rise to the appearance of organisms together with their environments.Uexküll himself provides an example: As his thought developed, he became to use Umwelt exclusively for the entire meshwork of functional cycles that make up both the organism’s world and the organism itself. Rather than beginning with two pre-givens which then become conjoined, it is from the myriad perception-action cycles that the entirety of the Umwelt grows.