| North American porcupines, as well as a range of other Hystricomorph rodents, engage in urine showering as part of courtship and other behaviors. |
| Three jaw muscle patterns, sciuromorph, myomorph, and hystricomorph are often used to designate major taxonomic divisions of the rodents. |
| Nutria are large hystricomorph South American rodents adapted to semi-aquatic environments. |
| Nevertheless, hystricomorph rodents are an exception among mammals, possessing an insulin molecule with many amino acid substitutions. |
