There are a few reasons why guinea pigs flatten.
When they’re scared they may flatten themselves in an attempt to make themselves appear smaller and less threatening to whatever is scaring them.
Additionally guinea pigs will sometimes flatten themselves out when they’re trying to sleep as this makes them less likely to be disturbed by predators or other animals.
Finally guinea pigs may also flatten themselves as a sign of submission when they’re around other guinea pigs that they don’t know well.
Is It Normal For Guinea Pigs To Flatten?
Yes it is normal for guinea pigs to flatten themselves out when they feel comfortable and safe.
When they are first introduced to a new environment they may be more cautious and stand up on their hind legs to get a better view.
But once they feel comfortable they will often lie down on their sides or backs to relax.