Here's why:
* Different Needs: Chinchillas and guinea pigs have vastly different needs regarding diet, temperature, and housing. Chinchillas need a dust bath, which guinea pigs can't use.
* Aggression: Guinea pigs are generally docile but can become territorial. Chinchillas, while generally friendly, are small and delicate, and a guinea pig could easily injure them.
* Disease: While both animals are susceptible to different diseases, there's a risk of cross-contamination.
Instead of housing them together, it's best to provide separate, suitable cages for each animal. This will ensure their health and well-being.