Galra headcanons except I don't know the first thing about anatomy and biology.
They have thicker skin that is incredibly hard to break, adapted for resilience, so once it does break, it takes a while to heal. If you have a serious enough wound, especially during war, they will not take you in and will not treat you.
A different distribution of blood vessels throughout their body, a bit more sparse so that when the skin breaks they usually do not lose blood, making for a bit of an eerie sight: deep gashes with nothing coming out. They do have another, slightly different bodily fluid that flows out and over wounds for an alternate and thicker version of human scabs. As stated before, their thick skin takes a while to regenerate, so this is necessary to avoid infection.
Due to the thick skin (and different pain receptors) Galra are a lot more numb to pain, and can take more hits, cuts and jabs than a human. This makes children much less fragile, and rough play, much more casual.
In the past, Galra had much thicker and stronger teeth as they are a primarily carnivorous species. But, mirroring humans, those grew weaker and more brittle over time with all the inventions and tools that made their food easier to chew and took away the need to split bone and muscle. A Galra with damaged teeth is seen as a disgrace, so, especially with age and especially influential, people, get metal replacements. They don't have a solid opinion on those replacements. Smooth, clean teeth will always be a beauty standard.
Their eyes are naturally adapted to a lower level of light because they slept in three shifts, one in the morning, another just after noon and the last in the late evening. They did most of their business at night, but mostly utilized the hours of the day, too. Some chose to forego the last, evening shift of sleep and instead lengthen the previous. They claimed that the things you did accomplish in the day would be blurred with sleep, anyway. All of this changed with Zarkon and the war, schedules shifting to be less sporadic, and sleep only happening in the night. This is not natural for a Galra and does nothing good for their health or eyesight.
Because they did do things throughout the day, and because they had meetings and arrangements with other species, they had to face light. For these occasions, the Galra could rely upon a film of sorts stored beside the eye, which wrapped overtop and muted the level of brightness, similar to Human sunglasses. Over the span of Zarkon's rule, this film became one with the eye, due to the conditions the Galra faced. In the past, the film being raised was a gesture of disapproval, essentially saying 'I want to see less of this', but fell out of use for obvious reasons. Some older Galra still squint/close their eyes with the same meaning.
Showing displeasure, anger, disgust and similar emotions when you felt them was incredibly important to the Galra, expressing them proof that you were honest and true to yourself, not making anything seem more pleasant for other people, like some other species did. So was being to the point and not spinning a hundred thousand words around their true meanings. This made those aforementioned species perceive them as violent and uncivilized, making it easier for Zarkon to spread more fear, and for the young Galra themselves, to believe the war to be their true purpose in life.
Galra are naturally strong-willed and would not easily back down. This is because of how well their prey adapted for its own survival, and how their persistence became vital. This translated into day-to-day life, and their belief that one should put their all into any given action, for the chance it goes right. It was primarily based on hope, but has since been twisted around into another tool of war, birthing the motto: "Victory or Death".
Similar to teeth, claws used to be stronger. Galra of the past would carry around extremely personal, claw-curved blades to use in the place of their ancestor's natural weapons. Usually it was more than one, hidden across their person in case something happened to the other. They were also personalized by pattern, hilt, thickness and length. This fell out of fashion, as Zarkon's soldiers usually carry blasters and big swords, but the importance of this old practice was not lost on all modern Galra.













