Rock Organism

"Insurance for in case the existence of life itself failed... If the first path of carbon-based life came to a dead-end, it was a fallback. A second path."

Rock Organisms (岩生物) are a silicon-based species of life, featured in the eighth part of the JoJo's Bizarre Adventure series, JoJolion.

They can be further classified into different subspecies, including Rock Humans (岩人間), Rock Animals (岩動物), and Rock Insects (岩昆虫).

Summary
Life cells that bonded from silicon were born at the same time as carbon-based cells. While these cells were few in number, the bodies that are formed by these cells are known as Rock Organisms. It is unknown why life diverged into those two paths. However, it could be that Rock Organisms were created as a fallback in case carbon-based life reached a dead end.

They eat plants, fruits, nuts, meat, fish, and all other forms of life. They enjoy honey, and all are allergic to mangoes. When a Rock Organism dies, it leaves no corpse, as it crumbles away into rocks.

Abilities
Rock Skin: Each Rock Organism has the ability to shift their outer appearance into a rock-like state and vice versa at will. In their rock form, they are able to camouflage into their surroundings, and improve their durability to some extent. When they do, most of their actions as a living being come to a halt and they can endure high temperatures or a lack of hydration.

Stands: 95% of Rock Humans possess Stands. The reason for the high proportion of Stand users in their population is likely due to them living in "special places" including the Devil's Palm and near the Wall Eyes in Morioh, which are locations known for being able to grant Stand abilities. Rock Animals and Rock Insects have unique abilities but they do not appear to be Stands.

Intangibility: Most Rock Animals and Rock Insects seem to be capable of intangibility to some degree. Iwasuke can phase through walls, Doremifasolati Do can phase through the ground, and Dododo De Dadada can phase through the ground as well as other objects.

Rock Humans
Rock Humans are the primary antagonistic force of JoJolion. Visually, they appear no differently than humans and can also procreate much like them. However, their behaviors after childbirth are a lot different and they have long hibernation habits. Rock Humans are fundamentally independent and some act as parasites within human society.

Rock Animals
Little is known of Rock Animals, but they are comfortable being pets and subservient to their owners. Iwasuke is listed as a further classification of a Rock Animal, stated to be a Rock Dog (岩犬).

Rock Insects
Rock Insects are insects found in nature, undiscovered by humans. Some of them can be carnivorous.