Nesomyids are small to medium rodents, and the largest is the size of a rat. They may look like mice, rats, voles, or hamsters, depending on the species and subfamily. They can either eat plant and meat totally, or insects totally. Their habits are also different, with some species climbing trees, and others digging holes in the ground to hide. They can give birth to the most four babies after being in the mother's womb for about six weeks.