I went on the guided hike the naturalists do on Wednesdays. They take up to 16 people on a two hour hike through a wash called the B wash. The B stands for bees, bats, burrows (holes) and wild burros (donkeys). In the center of the picture just above and a little left of the dark hole is a smaller hole. If you look at the smaller hole closely it looks like a mouth with long teeth hanging down inside it. It is actually a beehive and the "teeth" are the honey combs.
Of course the beehive is owned by killer bees. There are no native bees left in Arizona. They have all been hybridized with the African strain. They make great honey and the bee keepers have all learned how to deal with these more aggressive bees. If you are out in the wild and come upon a hive get away from it quickly. The only time they will attack is to defend their hive and you have to get fairly close to it for them to get aggresive. There were several hives in this cliff wall and they were far enough up from the bottom of the wash that we didn't have to worry. Although there were a few bees flying around us and we were told not to swat at them. It could rile them up.
We saw bat caves and burro trails and lots of burrows. Most desert critters take shelter in some kind of hole in the dirt. We also got to see antlions. They are very small insects that actually dig sand traps. They wait at the bottom of their trap for their prey - ants.