Chicago Field Museum

Analysis of the teeth of the man-eating lions of Tsavo suggests it wasn't dire circumstances but dental disease that drove the legendary lions to eat an estimated 35 people in Kenya in the late 1800s, a new study reports.

Why it matters: The findings reveal the many factors that can influence lion behavior and could inform conservation efforts. As human populations increase and prey decreases, man-eating could become a viable option for lions, the researchers wrote.

Lions rarely eat humans. The theory had long been that when they do, it's because of a shortage of prey — caused, in the case of the Tsavo lions, by a drought. The new findings suggest humans can be an easy alternative to supplement a lion's diet whether there are prey shortages or a lion is injured.

Methodology: Researchers from Chicago's Field Museum, where the two lions are part of the collection, and Vanderbilt University analyzed the surface of the lion's teeth with 3D imaging for wear associated with their diet. They compared them to zoo lions, wild lions, cheetahs (which do not eat bones) and hyenas (which scavenge and eat entire carcasses). If the lions were desperate and scavenging for food, they expected to see evidence of bone-crunching on their teeth, similar to hyenas.

What they found: The Tsavo lion that ate the most people had a severe dental disease that would have made it difficult to hunt prey like zebra and buffalo. The microscopic patterns on the teeth of the man-eating lions were smooth and most similar to zoo lions, which are fed soft foods like beef, and cheetahs, indicating the Tsavo lions were not fully consuming carcasses.

Parting perspective:

"We don't like to think of ourselves on the menu but we are," -- Laura DeSantis, Vanderbilt University.

Go deeper

Updated 26 mins ago - Politics & Policy

Coronavirus dashboard

Illustration: Aïda Amer/Axios

  1. Global: Total confirmed cases as of 3 p.m. ET: 33,217,895 — Total deaths: 999,273 — Total recoveries: 22,975,269Map.
  2. U.S.: Total confirmed cases as of 3 p.m. ET: 7,128,774 — Total deaths: 204,881 — Total recoveries: 2,766,280 — Total tests: 101,298,794Map.
  3. States: Cuomo extends New York moratorium on evictions until 2021.
  4. Business: Companies are still holding back earnings guidance.
  5. Health: The childless vaccine — Why kids get less severe coronavirus infections.
  6. World: India the second country after U.S. to hit 6 million cases.
27 mins ago - Podcasts

Digging into Trump's taxes

President Trump paid no federal income tax in 10 of the past 15 years, and just $750 in 2016 and 2017, according to a new report from the New York Times. He also is reported to have hundreds of millions of dollars in outstanding debts, most of which would come due during a second term.

Axios Re:Cap focuses on what is and isn't surprising about the revelations, plus how real estate developers are taxed, with Francine McKenna, an independent financial journalist and certified public accountant.

Pennsylvania GOP asks Supreme Court to halt mail-in ballot extension

Applications for mail-in ballots in Reading, Pennsylvania. Photo: Ben Hasty/MediaNews Group/Reading Eagle via Getty Images

Republicans in Pennsylvania on Monday asked the U.S. Supreme Court to halt a major state court ruling that extended the deadlines for mail-in ballots to several days after the election, The Morning Call reports.

Why it matters: It's the first election-related test for the Supreme Court since the death of Justice Ruth Bader Ginsburg, and could decide the fate of thousands of ballots in a crucial swing state that President Trump won in 2016. What the court decides could signal how it would deal with similar election-related litigation in other states.