What Mesoamerican people founded the Yucuita site?
Yucuita:  It was founded by the Mixtec civilization in the pre-Classic Period as a small village dedicated to agriculture and obsidian. Mixtec: The Mixtec , , or Mixtecos, are indigenous Mesoamerican peoples of Mexico inhabiting the region known as La Mixteca of Oaxaca and Puebla as well as the state of Guerrero's Región Montañas, and Región Costa Chica, which covers parts of the Mexican states of Oaxaca, Guerrero and Puebla.
Mixtec