smells suddenly into the tank, because the tank is considered by the gerbils to be their territory. Gerbils are active and appreciate a running or exercise wheel. Repetitive corner digging can be minimized by providing tunnels while gerbils are in their young, formative months. As with most animals, they appreciate a secure, private area that is dark for sleeping. A common misunderstanding when purchasing a home for pet gerbils is they can live in housing designed for hamsters and mice. This is not correct, as they need to be able to dig tunnel systems. The common plastic items inside of hamster and mouse cages is inappropriate for gerbils due to their ability to gnaw through it very quickly. Plastic can cause serious health issues for all animals if ingested, therefore many owners refrain from having any plastic in the tank and rely entirely on wooden toys. Information from gerbil societies from throughout the globe is conflicting with regards to tank sizing. However, a common minimum given appears to be per gerbil. Reasons for popularity The several reasons for the popularity of gerbils as household pets include: The animals are typically not aggressive, and they rarely bite unprovoked or without stress. They are small and easy to handle, since they are sociable creatures that enjoy the company of humans and other gerbils. Gerbils also have adapted their kidneys to produce a minimum of waste to conserve body fluids, which makes them very clean with little odor. Gerbils have many different aesthetic coat patterns, such as pied slate, described below. Health concerns Teeth problems Misalignment of incisors due to injury or malnutrition may result in overgrowth, which can cause injury to the roof of the mouth. Symptoms include a dropped or loss of appetite, drooling, weight loss, or foul breath. The teeth must be clipped by a veterinarian regularly for as long as required. Trauma Common injuries are caused by gerbils being dropped or falling, often while inside of a hamster ball, which can cause broken limbs or a fractured spine (for which there is no cure). Neglect A common problem for all small rodents is neglect, which can cause the gerbils to not receive adequate food and water, causing serious health concerns, including dehydration, starvation, stomach ulcers, eating of bedding material, and cannibalism. Epilepsy Between 20 and 50% of pet gerbils have the seizure disorder epilepsy. The seizures are thought to