1, you mean it didn't turn red at first, but it turned red at the beginning of dissection? (The eyes can see the process of change)
2. If you mean that the body is red from the beginning, then this phenomenon is normal, called lividity. The reason for the formation is that after death, blood will deposit downward due to gravity, so the corpse spot will only appear in the lower part of the body (the dead person's posture is different, and the place where the corpse spot appears is different).
3. It takes time to form corpse spots. Judging from the time of death, the lividity gradually formed in 0~ 12 hours, and the color was very light.
After 12~, the color of lividity deepened and finally became clear.
So the body has no color at first, and after a night, or a day, it will turn red.
If the above is not the kind of change you want to talk about, then ask.
Pure hands, please adopt. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .