These lizards can sometimes exceed two meters in total length. They are top predators, eating many other species of vertebrates, including smaller individuals of their own species as well as other species of monitor lizards. Monitor lizards are large and impressive. They are often the centerpiece of reptile house exhibits. Monitors are not particularly tractable research subjects, but these magnificent lizards have received an extraordinary amount of attention from devoted students.
Many monitor lizards are top predators.
Monitor lizards live in a wide variety of habitats, ranging from mangrove swamps to dense forests to savannas to arid deserts. A Pleistocene fossil monitor from Australia is estimated to have reached 5 m in total length and to have weighed over 600 kg. Although monitors are morphologically conservative, they vary in mass by five orders of magnitude. There is proportionately almost as much difference in mass among species of monitor lizards as there is between a mouse and an elephant. Sands constitute a natural event recorder, leaving a record of what creatures have moved past.