DNA analysis of 1898’s lions reveals surprising diet, including human, giraffe, zebra

In the year 1898, two big male lions created chaos in Kenya. These lions caused terror among a group of bridge builders camped along the Tsavo River in Kenya.

These were no ordinary lions. Known as the Tsavo Man-Eaters, they stalked the camp at night, dragging their victims away into the darkness. They claimed the lives of 28 people.

Lt. Col. John Henry Patterson, the project’s civil engineer, was determined to stop the deadly attacks. After a relentless hunt, he managed to kill both lions.

Patterson gave the lions’ remains to the Field Museum in Chicago in 1925.

Fast forward to the present day. Scientists at the museum along with the University of Illinois Urbana-Champaign started a study to unravel the mystery of these infamous man-eaters.

Using advanced techniques like microscopy and genomics, they analyzed prey hairs carefully extracted from the lions’ teeth. These hairs held the key to understanding the lions’ diet and behavior.

The researchers discovered a surprising range of prey, including giraffe, human, oryx, waterbuck, wildebeest, and zebra. The lions even consumed two giraffes.

“While conducting ancient DNA research on other animals at FMNH, our team conceptualized the idea of applying ancient DNA methodologies to these hair samples to further investigate prey species,” Alida de Flamingh, who led the hairs’ genomic analysis, told Interesting Engineering (IE) .

DNA analysis

The team started by examining the signs of DNA degradation over time.

After confirming their authenticity, they turned their attention to mitochondrial DNA (mtDNA). MtDNA is inherited maternally and can be used to trace lineage.

It’s advantageous for hair analysis due to mtDNA’s preservation. Moreover, the mitochondrial genome’s smaller size makes it easier to reconstruct potential prey species.

A database containing mtDNA profiles of potential prey species was created. It was used to compare and identify the mtDNA profiles extracted from the hairs of the lions.

The researchers also developed techniques to extract and analyze mtDNA from the hair fragments.

The analysis of the hair DNA revealed that the lions had consumed giraffes, humans, oryx, waterbuck, wildebeest, and zebra, as well as other lions.

“One surprising finding was the identification of hair from wildebeest. This is interesting because it raises questions about the historical distribution of wildebeest in the 1890s when the Tsavo lions lived,” de Flamingh told IE.

“It suggests that the Tsavo lions may have either traveled farther than previously believed, or that wildebeest were present in the Tsavo region during that time. The closest grazing area for wildebeest was over 50 miles from where the lions were killed in 1898 at the Tsavo-Athi confluence,” the author explained.

The lions were siblings

The lions were found to be siblings, as they had the “same maternally inherited mitochondrial genome.” They were probably born in Kenya or Tanzania.

Moreover, the researchers were surprised to find little evidence of buffalo in the lions’ diet, despite buffalo being their preferred prey today.

“Now that we have a molecular methodology that allows for the identification of prey species from very small (smaller than a picky fingernail) pieces of fragmented ancient hair, we are excited to expand this methodology to further analyze the different layers of compacted hair from tooth cavities,” de Flamingh said.

The layers in the tooth cavity represent the prey eaten throughout the lion’s life, with lower layers indicating earlier prey and upper layers representing more recent prey.

“This type of analysis can give insights into human-lion conflict which is still impacting many communities in the region and broadly in Africa. For example, if lions begin by hunting wildlife but then start attacking domestic animals, and eventually turn to preying on humans, we can develop strategies and recommendations to reduce these risks,” de Flamingh explained.

The new study significantly broadens the range of data that can be obtained from skulls and hairs collected from historical periods.

The findings were published in the journal Current Biology .