Celebrate World Gorilla Day with cushy mulch! Keepers pack habitat floors with mulch in Regenstein Center for African Apes to provide cushion and comfort for the gorillas and chimpanzees. As they age, these great apes experience arthritis, much in the same way as humans. Mulch and other squishy natural materials cushion the apes’ joints while they walk, run, and play. Select a share of spongy mulch for the gorillas today!