How a lightning strike leaves a branching mark
A lightning strike does not need to burn a fern-shaped pattern into the skin to leave one behind. As electrical current spreads over the body, it can affect tiny blood vessels close to the surface. The resulting temporary discoloration follows a branching path, making the mark look like a miniature tree or fern. These patterns are called Lichtenberg figures.
The name is also used for branching electrical patterns formed in insulating materials, but a mark on skin is a bodily response—not a design etched into it. The precise process that produces the skin pattern is not fully understood; the visible branches are associated with changes in superficial blood vessels.
Why the pattern fades
Because the mark is not a permanent scar carved into the skin, it can fade as the affected vessels recover and the discoloration clears. Its delicate, branching shape records where the strike’s effects reached near the surface—an unusual map of an electrical injury that may be temporary, even when the strike itself is dangerous.
