 |
"Long
before it's in the papers"
June 03, 2013
RETURN TO THE WORLD SCIENCE HOME PAGE
When humans were smaller, and crocs much bigger
May 9, 2012
Courtesy of the The University of Iowa
and World
Science staff
Although dinosaurs never
coexisted with humans, maybe they didn’t need
to. Research suggests another reptilian monster was on hand to scare the living daylights out of early humans or their kin: a crocodile whose shoulders easily came up to the height of an average man’s elbows at the time. A diagram showing the
relative sizes of ancient and modern crocodiles (large and small,
respectively) and ancient and modern humans (small and large,
respectively.) The black line marks a length of a meter
(3 feet 3 inches). (Illustration by Chris Brochu)
Dubbed Crocodylus thorbjarnarsoni, the beast is “the largest known true crocodile” in
our planet’s history, said University of Iowa geoscientist Christopher Brochu, whose research on it is published in the May 3 issue of the
Journal of Vertebrate Paleontology. “It may have exceeded 27 feet [8.2 meters] in length. By comparison, the largest recorded Nile crocodile was less than 21 feet, and most are much smaller.”
“We don’t actually have fossil human remains with croc bites,”
he said. “But the crocs were bigger than today’s crocodiles, and we were smaller, so there probably wasn’t much biting involved”—the process was
probably mainly a matter of swallowing.
Brochu’s paper describes the animal as a newly identified species, though the existence of the creature itself isn’t news. Fossils have been available at National Museum of Kenya in Nairobi, but were thought to be unusually large members of the modern Nile crocodile species, he explained. “We really don’t know where the Nile crocodile came from,” he said, “but it only appears after some of these prehistoric giants died out.”
The beast lived between two million and four million years ago in Kenya, added Brochu, who identified it as a new species based on the National Museum fossils. Some of these were found at sites known for major fossil discoveries of human ancestors, he added, so “it lived alongside our ancestors, and it probably ate them.” Early man had no plumbing and would have had to seek out water the same place other animals did—at rivers and lakes, right where crocs lie in wait.
He added 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 (1.2 meters) tall. Prehistoric humans or relatives living at the time included the ape-like
Australopithecus africanus and the more human-like Homo habilis, which appears later, starting about 2.5 million years ago in the fossil record.
It took four men—modern ones—just to lift a fossil skull of C. thorbjarnarsoni, Brochu said. He named the species is honor of his colleague John
Thorbjarnarson, a major crocodile authority who died of malaria 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 said.
This isn’t the first finding from Brochu involving ancient crocodiles. In 2010, he published a paper on a man-eating horned crocodile from Tanzania named
Crocodylus anthropophagus, a relative of the animal
featured in his new work.
* * *
Send us a comment
on this story, or send
it to a friend
|
||||
|
|
Although dinosaurs never co-existed with humans, maybe they didn’t need to, new research suggests. Another immense reptile was on hand to scare the living daylights out of early humans or their kin: a crocodile whose shoulders easily came up to the height of an average man’s elbows at the time. Dubbed Crocodylus thorbjarnarsoni, the beast is “the largest known true crocodile” in the planetsaid University of Iowa geoscientist Christopher Brochu, whose research on it is published in the May 3 issue of the Journal of Vertebrate Paleontology. “It may have exceeded 27 feet [8.2 meters] in length. By comparison, the largest recorded Nile crocodile was less than 21 feet, and most are much smaller.” “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,” he added. With this monster, named Crocodylus thorbjarnarsoni, the process was probably more a matter of swallowing than biting, he said. Brochu’s paper describes the animal as a newly identified species, though the existence of the creature itself isn’t news. Fossils have been available at National Museum of Kenya in Nairobi, but were thought to be unusually large members of the modern Nile crocodile species, he explained. “We really don’t know where the Nile crocodile came from,” he said, “but it only appears after some of these prehistoric giants died out.” The beast lived between two and four million years ago in Kenya, added Brochu, who identified it as a new species based on the National Museum fossils. Some of these were found at sites known for major fossil discoveries of human ancestors, he added, so “it lived alongside our ancestors, and it probably ate them.” Early man had no plumbing and would have had to seek out water the same place other animals did—at rivers and lakes, right where crocs lie in wait. He added 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 (1.2 meters) tall. Prehistoric humans or relatives living at the time included the ape-like Australopithecus africanus and the more human-like Homo habilis, which appears later, starting about 2.5 million years ago in the fossil record. It took four men—modern ones—just to lift a fossil skull of Crocodylus thorbjarnarsoni, Brochu said. He named the species is honor of his colleague John Thorbjarnarson, a major crocodile authority who died of malaria 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 said. This isn’t the first finding from Brochu involving eastern African fossils. In 2010, he published a paper on his finding a man-eating horned crocodile from Tanzania named Crocodylus anthropophagus—a relative of the croc featured in his new work.