they survive by adaptation
yes they come from the desert
No. Gerbils are omnivorous, meaning they eat both animal (well, insects) and plants, like humans. However, they are only opportunistic omnivorous, and can survive decently on a strictly vegetarian diet, but it is beneficial to give your gerbils a mealworm every now and then.
Depends about the dog and gerbil. You should bring your gerbil to a vet (if they do gerbils).
Gerbils are desert rodents, which means they are used to heat. So probably not very well.
Gerbils have evolved special kidneys and some other adaptations to survive with very little, if any, water.
Other gerbils.
Gerbils are an animal and can not be "invented".
Male gerbils can be neutered, but it is not recomended. Female gerbils should not be spayed. In general male gerbils should not be neutered unless there is a good reason for it.
no gerbils are not originally from the UK but instead from the deserts of Asia. But you can still buy gerbils in the UK
Yes, mice are smaller than gerbils, but I think gerbils are the right size.
They do have seizures (this is common in young gerbils)
No, they are not related. Gerbils are rodents, Rabbits are not.