BONE is the ecosystem's governance token, with a total supply of 250,000,000. BONE was designed to allow the Shib Army to have its voice heard by voting on proposals via the Doggy DAO.

Furthermore, BONE is the foundation upon which we built our ecosystem's proprietary Layer 2 network, Shibarium. With BONE as the gas token, Shibarium will enable the community to use decentralized apps on our very own network that is significantly faster and less expensive than the Ethereum blockchain.

https://blog.shibaswap.com/introduction-to-shibarium/