Modifying fish to make them more attractive as pets is an increasingly divisive issue. Historically, artificially dyeing fish was fairly common, with glassfish for example being injected with fluorescent dyes.
"Lacertilla", from Ernst Haeckel's Artforms of Nature, 1904
Fossil range: Jurassic - Recent
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Order: Squamata
Suborder: Lacertilia, Günther, 1867
Lizards are reptiles of the order Squamata, which they share with the snakes (Ophidians). They are usually four-legged, with external ear openings and movable eyelids. Species range in adult length from a few centimeters (some Caribbean geckos) to nearly three meters (Komodo dragons).

Dogs as pets