Researchers Have Discovered a New Giant 18-Million-Year-Old Crocodile Species That Inexplicably Disappeared

Large Crocodile Mouth Open

There are currently 18 living species of crocodiles. Large crocodiles can grow over 17 feet long.

Researchers find crocodile species that likely preyed on early humans.

Millions of years ago, giant dwarf crocodiles inhabited Africa that loved to eat our human ancestors.

Two new species of crocodiles have been discovered, according to a recent study headed by the University of Iowa. These crocodiles formerly inhabited east Africa between 18 million and 15 million years ago before inexplicably becoming extinct. Their findings were recently published in the journal The Anatomical Record. The species, known as giant dwarf crocodiles, is similar to the dwarf crocodiles that may today be found in central and western Africa.

But unlike their contemporary relatives, the huge dwarf crocodiles were much larger—hence the name. Rarely can dwarf crocodiles grow longer than 4 or 5 feet, but their prehistoric ancestors could reach lengths of up to 12 feet, making them among the most dangerous dangers to any animals they came across.

Researchers led by the University of Iowa have discovered two new species of crocodiles that roamed parts of Africa between 18 million and 15 million years ago and preyed on human ancestors. The Kinyang giant dwarf crocodiles (in gold) were up to four times the length of their modern relatives, dwarf crocodiles (shown in green). The new species discovery comes after an analysis of the skull of a Kinyang specimen. Credit:
Christopher Brochu, University of Iowa

“These were the biggest predators our ancestors faced,” says Christopher Brochu, professor in the Department of Earth and Environmental Sciences at Iowa and the study’s corresponding author. “They were opportunistic predators, just as crocodiles are today. It would have been downright perilous for ancient humans to head down to the river for a drink.”

Kinyang mabokoensis and Kinyang tchernovi are the names of the new species. They possessed big, conical teeth and short, deep snouts. Instead of opening straight upward like contemporary crocodiles, their noses opened somewhat up and to the front. Instead of being in the water, they waited for prey in the forest for the majority of the time.

“They had what looked like this big grin that made them look really happy, but they would bite your face off if you gave them the chance,” Brochu says.

Kinyang lived in the East Africa Rift Valley, in parts of present-day Kenya, in the early to middle Miocene period—a time when the region was largely blanketed by forests. However, both species seemed to go extinct starting about 15 million years ago with the end of the Miocene Climatic Optimum.

Why did they disappear? Brochu believes that less rain fell in the area as a result of climate change. As a result of the decrease in rainfall, forests gradually disappeared and were replaced by grasslands and mixed savanna woodlands. Kinyang was impacted by the shift in the environment because, according to the researchers, it likely favored woodland areas for breeding and hunting.

“Modern dwarf crocodiles are found exclusively in forested wetlands,” says Brochu, who has studied ancient and modern crocodiles for more than three decades. “Loss of habitat may have prompted a major change in the crocodiles found in the area.

“These same environmental changes have been linked to the rise of the larger bipedal primates that gave rise to modern humans,” Brochu adds.

Brochu acknowledges what caused the Kinyang to die out requires further testing, as the researchers are unable to determine precisely when the animals became extinct. Also, there is a gap in the fossil record between Kinyang and other crocodile lineages that came onto the scene beginning about 7 million years ago. The new arrivals included relatives of the Nile crocodile currently found in Kenya.

Brochu examined the specimens during several visits since 2007 to the National Museums of Kenya, in Nairobi.

The study was funded by the U.S. National Science Foundation, the National Geographic Society, the Leakey Foundation, the Wenner Gren Foundation for Anthropological Research, the Fulbright Collaborative Research Program, the Boise Fund of Oxford University, the IUCN Crocodile Specialist Group, the University of Iowa, the Karl und Marie Schack-Stiftung Fund and Vereinigung von Freunden und Förderern der Goethe-Universität Frankfurt, and the Ministerio de Universidades de España.

Reference: “Giant dwarf crocodiles from the Miocene of Kenya and crocodylid faunal dynamics in the late Cenozoic of East Africa” by Christopher A. Brochu, Ane de Celis, Amanda J. Adams, Stephanie K. Drumheller, Jennifer H. Nestler, Brenda R. Benefit, Aryeh Grossman, Francis Kirera, Thomas Lehmann, Cynthia Liutkus-Pierce, Fredrick K. Manthi, Monte L. McCrossin, Kieran P. McNulty and Rose Nyaboke Juma, 8 June 2022, The Anatomical Record.
DOI: 10.1002/ar.25005


View Comments

  • It is just like voay pterosaur duckbill dinosaur crest skull crocodile not like today dwarf crocodile they lack fuse nose.fuse nose are rare for crocodile and it’s ancestor American gator Chinese gator it is fuse the caiman gator it is not fuse .I wonder if it has dome skull like mammal dwarf crocodile dwarf caiman .out any crocodile I want to know more about them probaly have a lot dinosaur feature like dwarf caiman because they are land base crocodile .That fossil nose is more like early land mesoeucrocodylia they have fully mammal land nose like theropod dinosaur.

  • I’m confused. I didn’t know there was an Africa that liked to eat our ancestors. Did the ground open up and swallow them? I know there was a lot of tectonics going on in the distant past, but not as much in the era discussed here.

  • The title is wrong. The article goes on to explain a very feasible hypothesis for why these species did not survive. When grabbing headlines Trump's good science writing leads to why people question Science in the first place. Come on Scitechdaily. Do better

    • Why did you feel a need to denigrate Trump when he is not mentioned in the article and had nothing to do with the research? Are you acknowledging that you suffer from Trump Derangement Syndrome? Get a life!

      • I hope this is sarcasm. If it isn't, I'm pretty sure the inclusion of Trump was either a voice to text or autocorrect error. I really hope you aren't a combination of being that pedantic and oblivious.

  • They may have eaten the occasional ape - there were a LOT more of them in the Miocene, but there sure weren't any hominins that far back. The article is very misleading on that.

    • Yes, the article is misleading. Whatever bipedal pre-hominins were around at the time – and, 15 million years ago, we can pretty well guarantee that none of them looked remotely human – these giant dwarf crocodiles were the "among most dangerous dangers" that they faced.
      This carelessly-written article infers that there were no other large predators in Africa at that time.

  • I find this article fascinating and informative. How many of these new/old crocs are in existence at present time,if known? And I would also state that mentioning Trump in regards to this article is irrelevant,and serves no purpose whatsoever! The topic is the new discovery not Trump!

  • Yes, Kendra seems to have succumbed to Trump Derangement Syndrome. It must be awful to walk around all day long with rumblings of Trump echoing in her tiny dinosaur brain.

  • Was the climate change 15 million years ago caused by the Flintstonemobile? Or is it a natural phenomena that’s gonna happen no matter what.

  • It appears that TDS is still afflicting leftist snowflakes in 2022. It's hilarious that Trump still lives in the heads of these pathetic individuals.

  • My My, People. Please be advised of the following: Kendra was NOT referring to Trump the former president thing. The context readily implies the term trump, which existed before the former president, is being used to explain how one thing supersedes another. It’s a term, people. Ironic that folks are saying she’s making this article about Trump, when it is actually them. Geez. So ready to jump to negativity with the get a life type of comments, and so unnecessary. Allow kindness to take the lead a little more, perhaps.

    • This is indeed the case, though Kendra incorrectly using a capital ‘T’ didn’t help matters.

University of Iowa

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