According to the text. Why did the protagonist believe that axolotls were the strangest animals on Boulevard de Port Royal?

From the text:

Above all else, their eyes obsessed me. In the standing tanks on either side of them, different fishes showed me the simple stupidity of their handsome eyes so similar to our own. The eyes of the axolotls spoke to me of the presence of a different life, of another way of seeing. Glueing my face to the glass (the guard would cough fussily once in a while), I tried to see better those diminutive golden points, that entrance to the infinitely slow and remote world of these rosy creatures. It was useless to tap with one finger on the glass directly in front of their faces; they never gave the least reaction. The golden eyes continued burning with their soft, terrible light; they continued looking at me from an unfathomable depth which made me dizzy.