the blockchain can exist without bitcoin.
400 altcoins prove this.
but bitcoin/altcoins cannot exist without a blockchain
what about another blockchain wannabe sites?
if you mean ripple, if you mean stella, nxt, etc.. most of these are actually SQL databases just pretending to be blockchains..
but they are a whole different issue and much more closer to what fiat is, than a blockchain
but either way the point is that a blockchain such as litecoin does not have a single bitcoin attached to it.
neither do the other altcoins that have a blockchain.
thus, as i said.. a blockchain does not need bitcoin because it can use any token/coin.
but bitcoin wont exist without a blockchain