Nav: Home

UI professor identifies largest known crocodile

May 09, 2012

A crocodile large enough to swallow humans once lived in East Africa, according to a University of Iowa researcher.

"It's the largest known true crocodile," says Christopher Brochu, associate professor of geoscience. "It may have exceeded 27 feet in length. By comparison, the largest recorded Nile crocodile was less than 21 feet, and most are much smaller."

Brochu's paper on the discovery of a new crocodile species was just published in the May 3 issue of the Journal of Vertebrate Paleontology. The new species lived between 2 and 4 million years ago in Kenya. It resembled its living cousin, the Nile crocodile, but was more massive.

He recognized the new species from fossils that he examined three years ago at the National Museum of Kenya in Nairobi. Some were found at sites known for important human fossil discoveries. "It lived alongside our ancestors, and it probably ate them," Brochu says. He explains that although the fossils contain no evidence of human/reptile encounters, crocodiles generally eat whatever they can swallow, and humans of that time period would have stood no more than four feet tall.

"We don't actually have fossil human remains with croc bites, but the crocs were bigger than today's crocodiles, and we were smaller, so there probably wasn't much biting involved," Brochu says.

He adds that there likely would have been ample opportunity for humans to encounter crocs. That's because early man, along with other animals, would have had to seek water at rivers and lakes where crocodiles lie in wait.

Regarding the name he gave to the new species, Brochu said there was never a doubt.

The crocodile Crocodylus thorbjarnarsoni is named after John Thorbjarnarson, famed crocodile expert and Brochu's colleague who died of malaria while in the field several years ago.

"He was a giant in the field, so it only made sense to name a giant after him," Brochu says. "I certainly miss him, and I needed to honor him in some way. I couldn't not do it."

Among the skills needed for one to discover a new species of crocodile is, apparently, a keen eye.

Not that the fossilized crocodile head is small--it took four men to lift it. But other experts had seen the fossil without realizing it was a new species. Brochu points out that the Nairobi collection is "beautiful" and contains many fossils that have been incompletely studied. "So many discoveries could yet be made," he says.

In fact, this isn't the first time Brochu has made a discovery involving fossils from eastern Africa. In 2010, he published a paper on his finding a man-eating horned crocodile from Tanzania named Crocodylus anthropophagus--a crocodile related to his most recent discovery.

Brochu says Crocodylus thorbjarnarsoni is not directly related to the present-day Nile crocodile. This suggests that the Nile crocodile is a fairly young species and not an ancient "living fossil," as many people believe. "We really don't know where the Nile crocodile came from," Brochu says, "but it only appears after some of these prehistoric giants died out."

-end-

The work was funded in part by the National Science Foundation and the UI Obermann Center for Advanced Studies.

University of Iowa
Charred flowers and the fossil record
One of the main types of fossil used to understand the first flowering plants (angiosperms) are charred flowers.
Scientists find world's oldest fossil mushroom
Roughly 115 million years ago, when the ancient supercontinent Gondwana was breaking apart, a mushroom fell into a river and began an improbable journey.
The oldest fossil giant penguin
Together with colleagues from New Zealand, Senckenberg scientist Dr. Gerald Mayr described a recently discovered fossil of a giant penguin with a body length of around 150 centimeters.
Rare fossil discovery raises questions
Adult and juvenile remains of a giant rodent species (Isostylomys laurdillardi) have been uncovered by researchers, in the Río de la Plata coastal region of southern Uruguay, raising questions about classification within dinomids.
Fossil discovery rewrites understanding of reproductive evolution
A remarkable 250-million-year-old 'terrible-headed lizard' fossil found in China shows an embryo inside the mother -- clear evidence for live birth.
A 'transitional fossil' debunked
Snakes are a very diverse group of present-day reptiles, with nearly 3,600 known species.
Tiny fossil horses put their back into it
A new study reveals that tiny fossil ancestors of modern horses may have moved quite differently to their living counterparts.
New technologies to eliminate fossil fuel use in the sugar industry
QUT researchers are developing and testing new technologies as part of a $5.7 million three-year project with the potential to eliminate the use of fossil fuels in the sugar industry.
Many species now going extinct may vanish without a fossil trace
Scientists struggle to compare the magnitude of Earth's ongoing sixth mass-extinction event with the five great die-offs of prehistory.
The 'ugliest fossil reptiles' who roamed China
Long before the dinosaurs, hefty herbivores called pareiasaurs ruled the Earth.

Best Science Podcasts 2017

We have hand picked the best science podcasts for 2017. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.

Now Playing: Radiolab

Truth Trolls
Today, a third story of folks relentlessly searching for the truth. But this time, the truth seekers are an unlikely bunch... internet trolls.


Now Playing: TED Radio Hour

Rethinking School
For most of modern history, humans have placed smaller humans in institutions called schools. But what parts of this model still work? And what must change? This hour, TED speakers rethink education.TED speakers include teacher Tyler DeWitt, social entrepreneur Sal Khan, international education expert Andreas Schleicher, and educator Linda Cliatt-Wayman.