Lizards
Thousands of species, from an inch long to ten feet. Many can drop the tail and leave it twitching, then grow a replacement that never quite matches.
Overview
Lizard spans everything from a gecko the length of a thumbnail to a monitor longer than a person, and the useful questions are the same in every case: how big does it get, does it need UVB, what does it eat, and does it want to be handled.
Most of what goes wrong in lizard keeping is answered by two of those. An animal bought at hatchling size in a tank sized for a hatchling, and an animal kept without the light it needs to use its calcium.
Temperament
By species, and the range is total. Bearded dragons are genuinely tolerant of people, chameleons are stressed by being looked at, and large monitors are intelligent animals that require experience rather than enthusiasm.
Almost universally, males of the same species should not share an enclosure. Almost as universally, a lizard that has somewhere to hide is a calmer lizard than one that does not, even if it means seeing less of it.
Care and grooming
Insects, greens or whole prey depending on the species, and the supplementation regime matters as much as the food. Insects alone carry the wrong calcium to phosphorus ratio, so they are gut loaded and dusted.
Nutritional secondary hyperparathyroidism is the most common bone disease in reptile practice, and it comes from a poor calcium to phosphorus ratio, a lack of vitamin D3, missing UVB, or an enclosure that is not warm enough. It is a husbandry disease, which is to say it is preventable and it is nobody else's fault.
Living and exercise
By species, always with a warm end and a cool one, because a lizard has no internal thermostat and regulates by moving between temperatures. An enclosure at one temperature takes that control away.
UVB is required for most day active species. Reptiles and amphibians commonly carry Salmonella in their digestive tracts, healthy looking animals included, so hands are washed with soap and running water after handling one or anything from its enclosure.
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