Gerbils are a great small animal pet. Their bodies will grow to about 3-6 inches long (plus another 3-6 inches in tail length) and they weigh only an ounce or two making them easy to handle.
Many small animals are mostly active at night, but gerbils are active during the day, which makes them more fun. Gerbils are very social, and love to be kept in pairs or small groups. Be forewarned that they reproduce rapidly, so groups of same-sex gerbils are wiser unless you want a lot of gerbils!
Hamsters come in two sizes, full-sized hamsters which grow to 4-6 inches long and dwarf hamsters which are 2-3 inches in size. Each size has several breeds, the main differences are in color and length of coat. Life expectancy is 2-3 years.
Besides size, the major difference between the two types of hamsters is that full-size hamsters must be kept alone in a cage, while dwarf hamsters do best with a couple of cage mates (of the same sex and breed). Dwarf hamsters are more active than full-sized breeds and actually require more space to be happy.
Despite their name, guinea pigs are not pigs and they aren't from Guinea. They are small rodents originally found in the Andes Mountains in South America. Keeping with the pig name, adult females are called sows, adult males are known as bores, but their offspring are known as pups. Guinea pigs are also known as cavies.
Guinea pigs are large rodents, growing up to 10-15 inches in length (with almost no tail) and weighing up to 3 pounds. They usually will live 4-5 years.
Rabbits are becoming more popular as house pets every year. One reason for this trend is that they can be litter trained like a cat.
An indoor house rabbit can live from 5-10 years and provide a lot of family pleasure. Rabbits are playful and love interacting with people. They can also do well with cats and dogs if introduced carefully. However, they may become violent if put in the same cage with another rabbit if the two haven't bonded.
Many people get queasy when they think of having a rat as a pet...but they may be one of the best small animals to keep as pets!
Rats are very clean animals, spending as much as a third of their waking time grooming themselves. They are also intelligent and can be trained to come to their name and do simple tricks.
Because they are intelligent and very sociable, it's a good idea to have more than one rat. In fact, it can make training your rat even easier than if you just have one, since your rats will be more confident and outgoing. Be sure both your rats are the same sex unless you plan on raising them.