法老墓内壁上的褐色污点是真菌丛，这说明当时下葬仓促。

The tomb of King Tutenkhamen—better known as King Tut—has raised many questions over the years. What killed the young king? And—what’s the weird stuff on the walls?

Since the tomb was opened in 1922, tourists have peered at the elaborately painted walls. And some strange brown stains. Are the brown spots caused by contamination from visitors? Are they threatening the paintings? Or the health of the tourists?

The Egyptian Supreme Council of Antiquities asked the Getty Conservation Institute. They in turn posed the question to Harvard microbiologist Ralph Mitchell. His lab cultured material from the spots and sequenced its DNA. It turns out that the brown marks contain melanins—by-products of fungus metabolism. But the fungus is no longer alive. And photos show that the spots haven’t grown in the past almost 90 years.

Mitchell thinks this evidence indicates that King Tut was buried in a hurry. Because the paint on the walls was probably still wet. And that moisture, along with the body and the food buried there, would have fed the wall fungus, until the tomb ultimately dried out. But why the hasty funeral? Just another bit of intrigue surrounding the boy king.

—Cynthia Graber