Since the 4,300-year-old tomb was discovered outside Cairo in 1964, Egyptologists have known the names of the two men buried there -Niankhkhnum and Khnumhotep- and their occupation, manicurists to the king. But why were they embracing?

Over the years, the tomb's wall art has been subjected to learned analysis, inspiring considerable speculation. One interpretation is that the two men are brothers, probably identical twins, and this may be the earliest known depiction of twins. Another is that the men had a homosexual relationship, a more recent view that has gained support among gay advocates.

Now, an Egyptologist at New York University has stepped into the debate with a third interpretation. He has marshaled circumstantial evidence that the two menmay have been conjoined twins, popularly known as Siamese twins.