Overview
- A team led by Iwate University published the study in Current Biology on Aug. 19–20, 2026, reporting chemical and behavioral evidence that links specific urine molecules to individual identity.
- Behavior tests showed domestic cats sniff less of a repeated urine sample, show more flehmen toward unfamiliar urine, and can detect changes when only the identified fatty acids are swapped.
- Chemical analyses found 13 branched‑chain fatty acids whose combinations differ between cats but stay stable within the same individual and remain detectable in urine samples for at least 24 hours at room temperature.
- Tissue work localized the fatty acids to neutral lipids stored as lipid droplets in the renal cortex, leading the authors to propose that those droplets could buffer short‑term changes and preserve a consistent scent signature.
- Similar compounds and renal droplets were found across multiple wild felids, suggesting evolutionary spread, and the team says possible uses include noninvasive monitoring of big cats and new approaches to odor control, though those applications remain speculative and need more research.