Randolph E. Schmid, Associated Press Yahoo News 3 Nov 09;
WASHINGTON – The nightly attacks by two man-eating lions terrified railway workers and brought construction to a halt in one of east Africa's most notorious onslaughts more than a hundred years ago. But the death toll, scientists now say, wasn't as high as previously thought.
Over nine months the two voracious hunters claimed 35 lives — no small figure, but much less than some accounts of as many as 135 victims.
It was 1898, when laborers from India and local natives building the Uganda Railroad across Kenya became the prey for the pair, a case that has been the subject of numerous accounts and at least three movies.
The death toll had been estimated at 28 railway workers and "scores of unfortunate African natives," with the total ranging as high as 135. Delay of the railroad was even subject to debate in Britain's House of Commons.
Scientists hoping to figure out the actual number of people eaten decided to study the remains of the two male lions, now on display at the Field Museum of Natural History in Chicago, testing the types of carbon and nitrogen in their teeth and hair.
Those chemical ratios were compared with the carbon and nitrogen found in modern lions in the region, in lions' normal prey animals and in humans.
Bones and teeth store carbon and nitrogen isotopes over long periods, while the ratios in hair change more rapidly, allowing the scientists to determine the long-term diet and how it changed in the lions' last months.
Humans made up at least half of the diet of one of the lions in the last months of his life, consuming at least 24 people, they concluded. The other lion had eaten 11 people, they found.
In other words, even a century later, you are what you eat.
Researchers led by anthropologist Nathaniel J. Dominy and Justin D. Yeakel of the University of California, Santa Cruz, report in Tuesday's edition of Proceedings of the National Academy of Sciences.
They noted that estimates of the death toll reported at the time ranged from 28 reported by the Ugandan Railway Company, to 135, claimed by Lt. Col. John H. Patterson, a British officer who killed the lions in December, 1898.
The researchers did note that their study covers only the number of people eaten, while the number killed may have been higher. They said the death toll may have been as high as 75.
The killings occurred at a time when drought and disease sharply reduced the number of grazing animals that are the normal food for the lions, the report added, while at the same time construction of the railway brought an increased number of people into the area.
In addition, the researchers said the two lions seem to have cooperated in their hunting efforts. That's not unusual when they are after large prey like buffalo and zebra, but isn't necessary when after something smaller, like people.
However, one of the lions had severe dental problems and a jaw injury, probably limiting his ability to hunt, they reported. So the two may have worked together, with one eating more people and the other concentrating more heavily on other prey, but also eating humans.
"These findings underscore the complexity of what lions are capable of doing, and the complex interplay of costs and benefits that determine the size of their coalitions," Dominy said in a statement.
The research was funded by the Earthwatch Institute, the David and Lucille Packard Foundation and the UC-Santa Cruz Committee on Research.
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Man-eating lions of Tsavo less voracious than thought: study
Yahoo News 2 Nov 09;
CHICAGO (AFP) – The two man-eating lions of Tsavo which terrorized a railroad camp in Kenya and have inspired three Hollywood films may not have been as deadly as legend would have it, a study published Monday has found.
A British colonel hired to hunt the beasts claimed the lions killed 135 people in attacks which eventually became nightly occurrences and shut down work on the 1898 railway expansion.
That number was disputed by the Ugandan Railway Company, which estimated that just 28 people were killed. But Lieutenant Colonel John Patterson's vivid accounts of the nine months he pursued the lions lent credence to his claims.
By analyzing hair and bone samples from the pair of lions -- which Patterson sold to Chicago's Field Museum in 1924 after using their hides as rugs -- researchers were able to estimate that the railway company's account was closer to the truth.
"This has been a historical puzzle for years, and the discrepancy is now finally being addressed," said Nathaniel Dominy, an anthropology professor at the University of California, Santa Cruz.
"We can imagine that the railroad company might have had reasons to want to minimize the number of victims, and Patterson might have had reasons to inflate the number. So who do you trust? We're removing all those factors and getting down to data."
Researchers determined that one lion likely ate 11 humans and the other consumed 24 people during their final nine months.
They reached that conclusion by using isotope analysis to determine how much humans contributed to the diets of the two lions and then estimated how many people the lions would need to eat to survive.
Dominy said the analysis shows an "outside chance" that as many as 75 people were killed in total and noted that others may have been killed but not eaten. He said Patterson's claims of 135 deaths were likely exaggerated to help enhance his reputation.
The results suggest that during the final months of what Patterson described as a "reign of terror" fully half of one lion's diet consisted of humans, with the balance made up of mid-sized grazing animals such as impala and gazelles.
The other lion's diet was more heavily weighted on herbivores, which could mean the lions worked together to scatter both humans and wild game but did not fully share their kills.
Cooperative hunting is beneficial when stalking large prey like buffalo, but humans are small and slow enough that lions typically don't need to work together to make a kill, Dominy said.
Severe dental problems and a jaw injury suffered by one of the lions probably greatly inhibited its ability to hunt.
The lions may also have been drawn to the railroad workers and the animals in their camps for food after their conventional prey were depleted by drought and disease, he said.
The study was published in the Proceedings of the National Academy of Sciences.
