Help understanding this relative clause with の


Here is a panel from chapter one of 2001 Ya Monogatari

[![](https://i.stack.imgur.com/xya79.jpg)](https://i.stack.imgur.com/xya79.jpg)

I have trouble understanding the second text box

> はるかな太古からのイメージ... それまでの彼には想像すら不可能だった生き物たちの...

What イメージ means? The last の modifies which part? Is it an inverted sentence?

> それまでの彼には想像すら不可能だった生き物たちのはるかな太古からのイメージ




There is no inversion. の in 生き物たちの is a noun-linking particle meaning `'s`,
but it connects to 無重力の影響 in the next frame. This イメージ is simply "image" or
"vision". Note that 影響 is a paraphrase of イメージ. So there is a long subject
"(イメージ, which is 生き物たちの無重力の影響,)が..."

The basic structure of this sentence is:

> イメージ――影響が、彼の頭脳に何か不思議な作用を生じさせたのだろうか？  
>  Did the vision, or influence, have some mysterious effect on his brain?

And the full translation:

> はるかな太古からのイメージ――それまでの彼には想像すらできなかった生き物たちの無重力の影響が、彼の頭脳に何か不思議な作用を生じさせたのだろうか？
>
> Did the vision from the ancient times—the weightless influence of creatures
> he could not even imagine before—have some mysterious effect on his brain?

