There will be two primary areas of study: exploring the ecological and sociological implications of the pack animals’ return to the state.

Rasseem, Smithy, Mara, and the rest of the convoy marched behind us with all the pack animals.

Pigs are pack animals — not so different from being in a touring rock band, the singer and guitarist Marisa Dabice, 36, noted playfully.

Burros are not native to the West’s deserts — they are descendants of the pack animals that miners and prospectors used more than a century ago.

They are also an iconic symbol of the American Southwest, dating to their days as pack animals for people flocking to California during the Gold Rush.