King Tut's Curse!

We've all heard the story of the mummy's curse, and we've all heard the popular explanation — but you may not know the numbers behind the story. Today we're going to point our skeptical eye at King Tut's curse, and find out exactly how the story goes, explore the scientific-sounding explanation proposed by the media, and finally, we're going to look at what really happened.

In 1922 Howard Carter was exploring the Valley of the Kings in Egypt, with his friend and financial backer George Herbert, the 5th Earl of Carnarvon. After a 15 year search, they opened the fabulous tomb of King Tutankhamun, the most spectacular tomb found to date, and now known as KV62. Carter poked a hole through the seal and peered inside, and when Lord Carnarvon asked if he could see anything, Carter famously replied "Yes, wonderful things."

But things got less wonderful rather quickly, so the story goes. Front and center in the antechamber was a clay tablet, deciphered by one of Carter's colleagues, that read:

Death will slay with his wings whoever disturbs the peace of the pharaoh.

None of them seemed too concerned about Death's wings, because the archaeologists immediately proceeded to apply their early 20th century archaeological ignorance to King Tut and his goodies. Items were collected and broken, and even King Tut's mummy itself was said to have been chopped into pieces and set out in the sun where it quickly deteriorated. According to legend, Lord Carnarvon soon died from a mosquito bite; and simultaneously, his three-legged dog howled and dropped dead, and all the lights in the city of Cairo suddenly went out.

And then others of Carter's party began to die of mysterious causes. In fact, more than two dozen men were said to have fallen to the curse. Carter himself, it appears, had to suffer the fate of watching all his friends and associates drop off like flies all around him. Even his beloved pet canary was killed by a cobra in a freak incident. The newspapers trumpeted the terrors of the mummy's curse to all the world. Carter bore these miseries until he finally died himself, sixteen years after unleashing the curse.

Now the critical mind can easily find many causes for skepticism with this story:

• First, the accounts of the curse all come from 1920's-era newspapers, well known for sensationalism and expansion of facts to make great headlines. Reliable records of what happened to Carter's people after they left the dig are hard to come by. References to the simultaneous death of dogs, the canary, and the lights going out in Cairo are found only in these unreliable newspaper reports and so can be considered anecdotal at best.
   
• Second, Lord Carnarvon was known to be in pretty frail health at the time, and infection was a common cause of death. He had aggravated the mosquito bite on his cheek while shaving, and developed erysipelas resulting in septicemia and pneumonia. There was no curse needed to explain the dangers of these conditions.
   
• Third, the explanation that the curse's effect on Carter himself was to leave him alive and well while others died is clearly a post-hoc rationalization. Sure, I suppose it's possible that Carter's long healthy life could be evidence of a curse, but the lack of an effective curse is probably a better explanation for it.
   
• Fourth, and this goes back again to the pulp-fiction nature of the newspapers of the era, is the inconsistencies among various versions of the tale, notably the alleged stone tablet bearing the curse. It should be noted that there is no record of any written curse, either in Carter's own documents or in any modern collections; at least not associated with Tutankhamun's tomb specifically. Another post-hoc rationalization exists to explain the absence of a written record: It was expunged to avoid frightening the locals. Again, a better explanation is that such a written curse did not exist.
  

One of the first people to present a serious scientific explanation for the deaths associated with King Tut's curse was Dr. Caroline Stenger-Phillip, who proposed in 1986 that ancient mold in the tomb could have caused potentially fatal allergic reactions. Since fruits and vegetables and other organic items were buried in tombs, and since the tombs were completely hermetically sealed, it is plausible that mold spores could have existed and remained viable through the millennia.

This proposal has become known as "tomb toxins", and has been broadened to include other compounds, such as two molds that are found on ancient mummies, Aspergillus niger and Aspergillus flavus, and that can be potentially harmful to people with weakened immune systems. Bacteria are also found in tombs, including Pseudomonas and Staphylococcus. And don't forget the chemicals used in embalming the mummies: ammonia, formaldehyde, and hydrogen sulfide. Tomb toxins do sound like a plausible explanation for the mummy's curse. Most of us have heard this explanation at one time or another and thought "Ah, that explains it quite neatly."

But unfortunately, tomb toxins do not explain the deaths from Carter's group very well at all. Even in the unlikely event that members of Carter's party received lethal doses of any or all of the above, such death would have followed quite quickly; it wouldn't have been delayed by the months or years reported among the victims of King Tut's curse. Even Lord Carnarvon's death, the one most closely associated with the curse, occurred six months after he entered the tomb.

Another problem with the tomb toxin explanation is that it sounds good to a layperson, but it is, in fact, armchair science. It's a reasonably plausible idea, but one that has never actually happened in the real world. National Geographic is among those who have delved into this subject in detail, and found that working Egyptologists are not concerned about the possibility of tomb toxins. They've never heard of any colleagues suffering from it; thousands of tourists go in and out of the tombs every day with no ill effects, and even when Egyptologists do wear masks during excavations it's because of dust, not tomb toxins. F. DeWolfe Miller, professor of epidemiology at the University of Hawaii said "Given the sanitary conditions of the time in general, and those within Egypt in particular, Lord Carnarvon would likely have been safer inside the tomb than outside."

So we have two things at this point in our investigation: First, really weak and primarily anecdotal evidence that anything unusual happened; and second, a hypothesized cause that turns out to be quite a poor fit for the observed data. King Tut's curse is beginning to look about as withered up as he looks himself.

In 2002, the British Medical Journal published a study by Dr. Mark Nelson from Monash University in Australia. He decided to take a statistical look at the people who were actually there, and see if their dates of death actually were accelerated as a result of exposure to any possible curse. He performed a retrospective cohort study, which is a specific type of analysis based on medical records of certain groups of people. Nelson considered only the Westerners in Carter's party, since there was a difference in life expectancy between Westerners and Egyptians. He defined "exposure to the curse" as participation in any of four specific events where sacred seals were breached in the tomb, the sarcophagus, and the mummy itself. And then the number crunching began.

To better understand these results, it's necessary to comprehend what's meant by a "p-value". It's a term used by statisticians, and it refers to the probability that your test results could be due to normal random variations. A p-value of 0, the lowest possible, means there's a 0% chance that your test results are due to normal random variances, so low p-values generally mean that your results are significant. A p-value of 1, the highest possible, means that your results are 100% consistent with what we'd expect to see from normal random variations, therefore your results are quite probably insignificant.

Of 44 Westerners present, 25 were exposed to the curse. Those 25 lived to an average age of 70, while those not exposed lived to 75. The p-value of this difference was .87, so there's an 87% chance that this difference was merely due to chance. Average survival after the date of exposure was 20.8 years for the exposed group, and 28.9 years for the unexposed group. While this sounds like a large difference, the p-value was .95, meaning there's a 95% chance that you'd have such a difference anyway due to random variation. Nelson's conclusion: "There was no significant association between exposure to the mummy's curse and survival and thus no evidence to support the existence of a mummy's curse."

So, we end up with one piece of hard, testable evidence: Statistically speaking, nothing unusual happened in the Valley of the Kings; but pop culture gained one more rich layer of adventure fiction.

By Brian Dunning
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