More Than One Rat? You should ALWAYS, ALWAYS, ALWAYS, adopt at least two rats (of the same sex.) In the wild, rats live communally. (This means that they live in social groups with one another.) Rats depend on one another for social interaction. A rat needs a rat friend to help groom each other. A rat needs a rat friend for those times when you can't play with them. Multiple rats provide security for one another, making it easier for you to bond with them, because they will be less afraid. A lone rat tends to be more nervous. A lone rat is more prone to illness due to stress. A lone rat can develop neurotic tendencies. Rats are no less social with you, their human parent, no matter how many you have. Given proper attention, they will all develop an equally strong bond with you. If you have a lone rat, you should be spending at least four hours a day with them to meet their social needs. A lone rat can become very depressed if you leave them for a period of time, such as when going on a vacation. They could stop eating and even become sick. If your rat has a rat friend, they would have each other for comfort, and could bear the stress of not seeing you for an extended period of time much more effectively. Two rats are no more trouble to take care of than one, and the cost is virtually the same. If you already have a lone rat, you can still introduce them to a new rat friend, if done properly. (See "Introducing New Rats to Your Colony" within this Guidebook to learn more.) What do we recommend for the first time rat guardian to adopt? Two rats, of the same sex, from the same place, from the same enclosure. (See "Introducing New Rats to Your Colony" within this Guidebook to learn why.)