Topic: Biology

Scientists discovered a massive crocodile that lived around the same time as Lucy, an early human ancestor. The crocodile was about 12-15 feet long and weighed between 600-1,300 pounds.

More than 3 million years ago, the famous early human ancestor Lucy shared her landscape with a formidable predator. A massive crocodile with a distinctive hump on its snout likely posed one of the greatest dangers to these ancient hominins. Now, scientists have identified this reptile as a previously unknown species called Crocodylus lucivenator, meaning 'Lucy's hunter.'

The crocodile lived between 3.4 million and 3 million years ago in what is now Ethiopia, during the same period and in the same region inhabited by Lucy and her species, Australopithecus afarensis. The find also helped demonstrate that walking upright on two legs, known as bipedalism, evolved before larger brain size.

The newly identified crocodile was an impressive animal, measuring roughly 12 to 15 feet long and weighing between 600 and 1,300 pounds. It was the only crocodile known from the Hadar landscape, an environment that included shrublands, wetlands, rivers, and tree-lined waterways.

Researchers believe it was an ambush predator that spent much of its time concealed in the water, waiting for animals to approach for a drink. 'It was the largest predator in that ecosystem, more so than lions and hyenas, and the biggest threat to our ancestors who lived there during that time,' says Christopher Brochu, professor in the Department of Earth and Environmental Sciences at Iowa.

A Strange and Distinctive Crocodile

Brochu has spent 35 years studying ancient crocodilians. He first examined Crocodylus lucivenator specimens during a visit to a museum in Addis Ababa, Ethiopia, in 2016. 'I was just blown away because it had this really weird combination of character states,' Brochu recalls.

One of the crocodile's most unusual features was a prominent hump located in the middle of its snout. Similar structures are found in American crocodiles but not in Africa's Nile crocodiles. Researchers believe the hump may have played a role in courtship displays.

Fossils Reveal Ancient Behavior

To identify the new species, researchers analyzed 121 cataloged fossil remains, including skulls, teeth, and jaw fragments from dozens of individuals. The fossils were recovered from the Hadar Formation in Ethiopia's Afar region.

Why It Matters

This discovery helps us understand how early human ancestors lived alongside other predators and prey. It also shows that even ancient animals had unique features that helped them survive.

Key Facts

• The crocodile, Crocodylus lucivenator, was a massive predator that lived around the same time as Lucy, an early human ancestor.
• It measured roughly 12 to 15 feet long and weighed between 600 and 1,300 pounds.
• The crocodile had a distinctive hump on its snout, which may have played a role in courtship displays.
• Researchers analyzed 121 cataloged fossil remains to identify the new species.
• The discovery helps us understand how early human ancestors lived alongside other predators and prey.

Key Terms

Crocodylus lucivenator

A previously unknown species of crocodile that lived around the same time as Lucy

Implications

This discovery helps us understand how early human ancestors lived alongside other predators and prey. It also shows that even ancient animals had unique features that helped them survive.