The Bolivian Tree Lizard is a parasitic reptile that lays its eggs in other birds' nests, then eats the original eggs. The mother bird will continue to nurse the eggs thinking they are hers. After the eggs hatch, the young lizards eat the mother bird, too. Bart hatched a pair (whom he originally thought were the babies of a mother bird he accidentally shot) which he named Chirpy Boy and Bart Junior. When he brought them to the attention of the community a group of people in a bird-watching club (including his principal, Principal Skinner), they decided that the lizards needed to be killed to protect the native wildlife. However, with the help of his mother, Bart manages to flee with the lizards onto the roof; where both of them escape by gliding to the ground and running away. Bolivian Tree Lizards once took care of Springfield's pigeon problem, but they then possibly became extinct in Springfield because snakes were introduced into the wildlife to reduce their numbers (followed by a line-up of several other species to try and wipe the prior ones out).
Behind the Laughter
There is no such thing as the Bolivian Tree Lizard. This fictional species is a mix-match of real reptiles, combining the looks of a tree iguana, gliding membranes like those of South-East Asian dracos, the egg and bird-eating habits of snakes and how the dinosaur Oviraptor philoceratops was thought to have stolen other dinosaur eggs. The conduct of replacing birds' eggs with their own is probably inspired by the Cuckoo, one of the birds that Skinner - erroneously - claims to have been exterminated by them.
- Episode – "Bart the Mother"
- Episode – "Pay Pal" “Seen in the middle of “Pet The Lizards”
- Episode – "A Father's Watch" (couch gag)