James St. John / Wikimedia Commons
A mysterious and feared marine animal is slowly being demystified. Here’s what we know about the Dunkleosteus terrelli.
Some 360 million years ago, the shallow sea above present-day Cleveland was home to a fearsome predator: the Dunkleosteus terrelli.
This fish, known as the Cleveland Sea Monster, was 4.2 meters long and dominated the Upper Devonian seas with razor-sharp bony blades instead of teeth, which made it one of the largest and most ferocious arthrodires — an extinct group of shark-like fish, covered in bony armor on the head and torso, recalls .
“O The last major work to examine in detail the anatomy of the Dunkleosteus jaw was published in 1932.when the anatomy of arthrodires was still poorly understood,” said Russell Engelmana graduate student in biology at Case Western Reserve and lead author of the published this week in The Anatomical Record.
“Most of the work at that time was just focused on figuring out how the bones fit back together,” he comments.
Scientists have managed to discover three new aspects about these animals: they have jaw muscles similar to those of sharksone skull with a large amount of cartilage and they are an atypical case in evolution: despite being the classic example of arthrodires, Dunkleosteus was unusual among his relatives.
The specializations of the bone plates of Dunkleosteus and its relatives reflect a increasing adaptation to hunting of other large fish
“These findings highlight that arthrodires cannot be considered primitive, homogeneous animals,” Engelman said, “but rather a highly diverse group of fish that thrived and played many different ecological roles throughout their history.”
