We have more impermanent art today. Daniel Dancer creates art that HAS to last only a short time -- it's fashioned out of people! Mr. Dancer has worked with schools, groups, and companies to create living art that seems to have as big an impact on the people who are in it as the people who see it.
The Sky Grizzly
Badger Two Medicine area, Blackfeet Reservation, Montana, 2004. 400 Blackfeet members participated.
750 students and staff of Jewell Elementary School.
In addition to the 750 people, 12 yards of shredded bark for the "moon" and a truck load of black and white clothes form the Canada Goose flying across the moon.
"Living art" photographs have been created since the invention of photography. For instance, here's a shot by Arthur Mole and John Thomas from 1918, using 18,000 soldiers:
The Human Statue of Liberty
Mole and Thomas
This site of older photos is worth a look.