Our current domestic cat is domesticated by wild cats.
In order to survive, wild cats often ambush their prey. If the prey smells the cat’s excrement, it will escape, and the smell of the excrement will attract powerful natural enemies such as tigers and leopards. So wild cats always like to excrete near their nests, bury their urine and urine, and reduce their traces.
Although domesticated by humans, domestic cats still have some habits that preserve their ancestral instincts. They will find a hidden place, and usually a fixed place to defecate, defecate pulled out, they will use sand carefully buried.