Blockchain technology can be said to be a recent invention. It has come to bring trustless, traceable and immutable transactions. Smartcontracts cannot work without the features of the blockchain. You will be talking about something else other than Smart contracts if you lack a blockchain to carry them out.
Blockchain technology allows transactions to occur between two parties without the involvement of a third party. No cryptocurrency exists without a blockchain.
A blockchain has more than one layer. The first layer is the main or the base layer. The base layer takes the responsibility of protecting the blockchain. It ensures that transactions are immutable, cryptographically secure from a central governing body.
Layer 2 depends on the security of the first layer. As layer one depends on its immutability layer 2 depends on the security of the first layer.
This is how it works
Ethereum is a blockchain of its own. It uses Eth as its native coin therefore anyone building another coin or DApps on the App will use the coin to manoeuvre through the platform. Ethereum is immutable on its own and provides the security required for transactions that are being undertaken on the platform. It is the base layer. The second layer is where other coins and DApps are built.
On the other hand, the Shiba-Inu token exists on the Ethereum blockchain. It survives on the security and immutability of the base-layer which is Ethereum. If Ethereum is comprised in its immutability then Shiba-Inu will be at risk. It doesn’t run its own security.