Their wild habitat in Mongolia is mainly semi-deserts and sandy steppes cover in grasses, herbs, and shrubs. Although Mongolian Gerbils are naturally diurnal, pet rodents are more likely to be crepuscular - more active at dusk and dawn.
They would naturally live in a burrow system in the wild and a captive Mongolian Gerbils environment must allow them a minimum of 6 inches of a decent substrate in order to construct their tunnel networks. Hamster cages and modular systems are completely unsuitable.
Mongolian gerbils should not be kept alone, although adult gerbils can only be introduced safely to each other via the split-cage method. They are extremely territorial and would fight an intruder to the death. Female gerbils can be more likely to declan in later life than males although this may in part be due to poor breeding. If in doubt, girls are best kept in pairs whereas male gerbils can be stable in groups up to four providing you have enough space for a large tank.
Mongolian Gerbils live on average 3 - 5 years and come in a wide variety of colours and are a popular pet given their hardy nature and ease of taming. They have quite simple care requirements with the exception of the split-caging issues.
Gerbils are easy to tame if they have come from an ethical breeder or Rescue. Pet shop gerbils may initially be quite difficult due to the lack of socialising and poor conditions. See the section on handling for more information.