1) Their ears start to curl within 48 hours after birth.
2) Their mutant gene is represented by Cu.
3) The character Ray Smuckles, from the webcomic Achewood, has confessed to being an American Curl.
4) They are healthy and robust.
5) Their ears nevertheless need regular cleansing to avoid infections and requires mild managing to prevent damage.
6) Various breeding’s in between them and other breeds exposed a dominant inheritance of their gene.
7) The breed came from California, as the outcome of a spontaneous anomaly.
8) Due to its big hereditary swimming pool with non-pedigree cats, they usually are a healthy breed.