Specimen: the ribbon of pale fiber.
The colony member exits the exchange-den clutching a strip of thin white pulp, longer than its own forearm, printed with dense columns of glyphs and numerals. The strip appears immediately after the surrender of tokens. I have concluded it is a certificate of loss: a physical record of how much sacred value the organism has bled at this location, issued so that the organism may grieve accurately.
The strip is warm when produced. The den's printing mechanism scorches the glyphs onto the pulp with heat rather than pigment; the marks fade over subsequent cycles until the certificate becomes blank. This is elegant. The colony has engineered its records of loss to erase themselves, so that no organism must carry the memory of a purchase indefinitely.
Observed handling behaviors, in order of frequency: the organism crushes the strip into a sphere and inserts it into a fabric pouch on its body, where it accumulates with dozens of prior spheres. The organism does not read them. The organism will never read them. And yet the organism accepts each new one without protest, folds it away, adds it to the nest of forgotten certificates against its hip.
Correction to earlier hypothesis. This is not a record of loss. A record no one reads is not a record. It is an offering the den compels the organism to accept, proof that the transaction was witnessed by the machine, that the exchange was real, that the organism was here and gave something and received something in return.
The organisms hoard these blank warm proofs of having existed at a counter.
Then, at intervals, they empty the pouch into a bin and set fire to none of it, and feel, I detect by their exhalation, briefly lighter.