Gollum, who are you ?
« There are strange things living in the pools and lakes in the hearts of mountains : fish whose fathers swam in […] and never swam out again, while their eyes grew bigger ang bigger ang bigger from trying to see in the blackness »
J.R.R Tolkien, The Hobbit, Chapter V, Riddles in the dark
« It's the story of a hobbit gone wrong ». (Lehoucq R., Mangin L., Steyer J-B.,Tolkien et les sciences, éd. Belin).
Sméagol's transformation into Gollum, caused by the evil ring, is akin to a polymorphic mutation. Some of its physical characteristics allow him to be compared with cave-dwelling animals.
"Is this why Gollum prefers to travel at night? Are his large, bulging eyes sensitive to light? In any case, after centuries spent in the darkness of the Misty Mountains, the monster has developed other acuities: hearing and smell. This hypersensitivity combined with the evil power of the Ring and his sharp teeth ultimately make Gollum a dangerous predator. " (Op. cit, Gollum, la métamorphose du hobbit).
Like Gollum, who has been completely transformed by his life in a cave, cave dwellers have many special characteristics. Depigmentation or non-pigmentation is one of the most common characteristics of cave animals, as is the loss or reduction of eyesight.
The axolotl is black and normally lives in lakes, but leucitic (pigment-free) forms exist in caves and underground lakes.
Other animals have developed acoustic systems to move around in total darkness and are able to find a home on the walls of caves, such as bats.
As for the loris, a non-cavity animal, it finds its bearings in the dark thanks to its enormous bulging eyes... Which are reminiscent of those of Gollum!