This is CBS Eye on the World.

Here's John Batchelor.

This is CBSI on the world.

I'm John Batchel.

Continuing a conversation with the Egyptologist Toby Wilkinson.

The new book, The Last Dynasty, Ancient Egypt from Alexander the Great to Cleopatra.

This is too early in the world of affairs for Egyptologists and too ancient for the world of Roman historians.

And the professor has done us the favor of putting this piece together,

because this will emerge, of course, in Shakespeare in the 16th century,

and we're still keen on those dramas, 16th and 15th century and 15th century.

All of that will emerge as romance, and there's a great deal of romance ahead.

But now we begin the drama of the decline of the Ptolemae's.

Professor, four, five, and six are the decline themselves. Each of them were powerful, but

they were being hard pressed to maintain order because the family had pieces that turned on itself.

And one of the ways they tried to deal with is the Ptolemy's and their brothers and half-brothers and wives is that they would marry their sisters or marry their cousins or marry the daughter of a brother.

All of that is unacceptable behavior if I understand the Greeks.

However, the Egyptians regarded it as normal. Is that correct?

Well, the Egyptians certainly regarded it as normal. Is that correct? Well, the Egyptians certainly regarded as something that they were familiar with royal families doing.

So back in the pharonic period, pharaohs did marry their own daughters and their own sisters.

I mean, it wasn't commonplace, but it was accepted that kings behaved a bit

differently. So it was an acceptable thing for a royal family to do. It was completely taboo in the Greek

world. And this is interesting because here we have the Ptolemy's, although they're speaking Greek,

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