Did you know that cat litter was not invented until 1947? Up until then people kept cats outdoors, and cats eliminated in natural sand, dirt, and leaves. Ed Lowe, the inventor of kitty litter, shared some Fuller's Earth (clay) product with his neighbor and then soon after sold it in 5 pound bags to pet stores in Michigan. He went on to create Tidy Cat cat box filler in 1964, was the top producer of cat box filler by 1990, and sold his business for millions.
While it's been over 10,000 years since the house cat began living amongst humans, it's amazing to think what a short period of time cats have actually been confined to indoor living with us. This indoor confinement is the cause of many behavioral challenges, and because this has been so recent, little scientific data is available. Behavioral Specialists study the natural actions of cats and try to incorporate those into the confined spaces so the cat feels more at ease.