Perhaps, but again you are trying to use YOUR understanding of the matter and try to apply that to ancient people.
Ancient people who were not retards. Honestly how long do you think it would take to explain to someone that not everything that lives in the sea was a fish? Especially if you're God?
"Hey, Lebish, been meaning to tell you something. Not everything that lives in the sea is a "fish". That word pretty much just means those fleshy creatures with the white meat and the bones in 'em."
"Whatever you say, God."
In the Vietnamese language, there is only 1 word for "green" and "blue". Wait a second, were the Vietnamese in ancient times all colorblind?
Well, we don't have a word for the color of oranges, we have to refer to the fruit to describe it.
Were they all retarded enough to not notice the difference between something that is green and something that is blue?
What is the difference, exactly? Is it possible that people in English-speaking cultures are percieving a difference that isn't necessarily there simply because we have words for the difference?
You don't have to have a concept of the wavelength of light to understand that not everything in the sea is built the same way, and that fish are built differently than things that are not fish. You might quibble with the definition of the word "fish", at that point; but if you're speaking to the God of the Universe don't you think you'd take his word on what words mean?