The subfamily of Cholla cactus that can be seen in Joshua Tree National Monument's desert is also called "jumping cactus". I got a first-hand explanation for this nickname: absorbed in the making of a closeup picture, I did not notice how close my hand was to the plant, until it lightly brushed some spines: the joints detached instantly and became lodged in my skin, under wool gloves, with more spines seeming to jump at my hand when I moved it back. I had to use my knife's plier to get rid of the barbs...
They are also called "Teddy Bear" cholla cactus, for the evocative shape of their silhouette.
