Genson! Kodai Seibutsu-shi Pakky

Author: Retsu

Run: 2011–2012

Chapters: 23

Genres: Comedy, School

"Existing! Ancient Biological History Packy" (Genzon Kodai Seibutsushi Packy) is a Japanese manga work by Retsu. It was serialized in Shueisha's Weekly Shonen Jump from issue 49 in 2011 to issue 23 in 2012. A gag manga featuring Packy, a Pachycephalosaurus, as the main character. The number of episodes is counted as "Era XX". A special one-shot was published in the March 2012 issue of Saikyo Jump, and a short story was published in the Spring 2012 issue of Shonen Jump NEXT!.