I've been thinking about dwarfs and their depiction in classical fantasy for while now and concluded that I find it unrealistic and lazy. Some research showed me that the current fantasy dwarfs have their roots in the christian interpretation of norse legends about lesser earth spirits or ironically dark elves. Thus I decided to design my own dwarfs and stick to an earth spirits and subterranean creature theme without sacrificing many if the iconic dwarven features. My design is ready so far, yet it has some points which may or may not be issues. So I came here to hear some opinions on my dwarfs.
This will be the first question in a series of five, which I'll all like below once they are asked.
1 Bioluminescence for active vision
2 Mesothermic and regulateable metabolism
3 Finding caves
4 Evolutionary pressures
5 Beards must remain
As the first world was shattered into many spheres of existance a group of early hominids was displaced to a dark and hostile place where they could only survive underground. They adapted in many ways. Their noses and ears grew as the associated senses shaped. They grew smaller and more muscular to navigate the caves quicker. Their metabolism turned mesothermic and they gained control over it, allowing them to hibernate or lay low in times of famine ir to eat plenty to boost their strength and vitality. Unlike other subterranean creatures however they did not loose their eyesight. Instead their eyes grew bigger and incredibly light sensitive, so light-sensitive that they later developed nictitating membranes as a form of biological sunglasses to go to the upper-world. They illuminate their surroundings with their bioluminescent skin. This makes their skin blue and if they are exposed to sunlight it turns almost black, in the darjest caverns they have an very light blue taint. They do not glow very bright, in fact only their very sensetive vision allows them to use their light.
Does this kind if active sense of vision make sense for the dwarfs as subterranean critters and how exactly does it work? What is the optimal mechanism as there are two possibilities according to Wikipedia?
In some animals, the light is bacteriogenic, produced by symbiotic organisms such as Vibrio bacteria; in others, it is autogenic, produced by the animals themselves.
Is this the most practical approach to them having cave-nightvision or is there anything better I missed.