The fun became extinct when a 5-year-old boy got his head stuck at the American Museum of Natural History Wednesday.

The boy, who was visiting the Upper West Side museum with a camp group, was briefly stuck behind an introductory panel in the Hall of Advanced Mammals, a museum spokeswoman said.

The exhibition hall features extinct animals like mammoths, mastodons, saber-toothed cats, and giant ground sloths, according to the museum.

Museum staff were able to free the boy by loosening the panel from the wall, the spokeswoman said.