That is the experts point, which I disagree with. Its circular logic. It assumes the only way flies get to a body is on their own.
If flies don't normally leave the nice green golf course where food is plentiful to go searching off in the desert where food is not plentiful maybe the body in the desert gets its fair share of flies from the animals.
If anything or anybody shits in the open in a desert, a fly lands within 10 min, if not 10 sec, let me tell you. Trash, including fast food and ice cream containers, littered this area.
Would somebody who lives in one of the three driest major cities in the USA, Las Vegas, Albuquerque, and El Paso, please step in and tell this poster the truth about flies!
San Diego is much damper and more temperate.