Basically, you Sunny and knowcheeze are materialists. Materialism is only one explanation of existing things. There are others. And Sunny, you are asking a question that you already gave an answer to in a previous post.
Is oxygen non existent?
Believe it or not, lobster and crabs are crustaceans and are a part of the arthropod family, which include caterpillars, cockroaches, and spiders!