Rats make burrows because in the wild they burrow into the ground for homes. Rodents like to feel safe in their houses and they like to hide underground so that birds and other predators can't see them when they are sleeping.
The hamster is building a nest. They take pride in building their own homes and sometimes they sleep their since it's warmer.
You can help your hamster by giving it some hamster nest cotton from the pet supply store, or you can give it some unscented regular toilet paper. The hamster will use these to make the house comfier.
No. Neither rats or hedgehogs burrow.
A burrow
no,rats need bedding that they can burrow into
It makes a burrow
This is called bruxing, and it has a similar meaning to a cat purring.
It means very drunk. I think it came from a medieval torture method,where a rat was placed on the victim's stomach and a bucket placed on top of it. The bucket was then heated and the rat would burrow into the victim's stomach trying to escape. It would eventually come out of the victim's backside.The victim would be dead (from bleeding) by this stage. So being truly "rat-arsed" is not a good thing.
A platypus makes just one burrow for shelter, although the burrow may have mire than one entrance. During breeding season, a female platypus will dig a chamber at the end of the burrow, where she lays her eggs.
grass and soft mud
If they are regular, raspy noises, sort of like snoring, it may mean that your rat has a respiratory infection. You should get a vet to check it out, and prescribe antibiotics if necessary. Respiratory infections are dangerous for rats.
In the wild, it's a burrow. I'd imagine the term "cage" is just fine for domesticated rats though.
you have to put a heating pad under it
it means you have rat(s).