Evolutionists assume that the sea invertebrates that appear in the Cambrian stratum somehow evolved into fish in tens of million years. However, just as Cambrian invertebrates have no ancestors, there are no transitional links indicating that an evolution occurred between these invertebrates and fish. It should be noted that invertebrates and fish have enormous structural differences. Invertebrates have their hard tissues outside their bodies, whereas fish are vertebrates that have theirs on the inside. Such an enormous “evolution” would have taken billions of steps to be completed and there should be billions of transitional forms displaying them.