Like, I know that desert dwellers do it to protect their bodies from the sun, but isn’t that also an issue in the tropics?
There’s definitely a functional reason based on physics for this. I find I’m hotter working out without a shirt on, that I am if I have a loose shirt or singlet on.
I don’t actually know but maybe it has to do with high humidity favoring less clothing so your sweat helps cool you more effectively? Or perhaps the higher ease in finding shade in the tropics.
In the tropics your problem is heat and rain. Any material in the tropics will be taking in water, and when it rains it rains so hard your eyes will hurt from all the rain rubbing against them. Thin clothes dry fast, and no clothes is twice as good. If the sun is too hot just take a siesta.
In the desert, wind is your enemy because it sprays loose matter everywhere. Hence tents and flowing clothes for protection.
If you’re farming in the tropics you want long sleeve thin clothing to limit Sun damage. Broad hats are also ideal.
I’m no scientist but as someone from a tropical country, it has to do with humidity and covering yourself would make yourself sweat more. Also look up wet-bulb temperatures
As someone who lives in the tropics, humidity.
The air is humid here and sweat does not seem to evaporate quickly, the dew point here is also high. Covering yourself up like those in the Desert can be a bad idea when you are sweating, you would want to evaporate all that sweat as the evaporation seems to take all that heat energy out of the body.