First Face? Prehistoric Fish Was a Jaw-Dropper
The earliest known species with what we would recognize as a face was an armored, beady-eyed prehistoric fish, according to a new paper in the journal Nature.
The fish, entelognathus primordialis (meaning "primordial complete jaw"), is the oldest known animal to have face-forming jaw and cheek bones comparable to those of today's bony fishes and most terrestrial animals, including us.
"Entelognathus had a rather unprepossessing face," co-author Per Erik Ahlberg of Uppsala University told Discovery News. "The mouth was wide, the forehead low and flat, and the small, close-set and almost immobile eyes pointed forwards like a pair of car headlights."
Lead author Min Zhu, of the Chinese Academy of Sciences' Institute of Vertebrate Paleontology and Paleoanthropology, added that entelognathus was "a placoderm, an extinct grade of primitive armored fishes."
Zhu and colleagues found the 419-million-year-old fish at Xiaoxiang Reservoir in Quijing, Yunnann, China. He said that at first it didn't seem very interesting, covered with material from the site, but when they brought it back to the lab and cleaned it up, the fish's "superb preservation," armor and facial bones became evident.
Before fish had faces like those of modern species, they looked downright bizarre, suggests Matt Friedman, a lecturer in paleobiology at the University of Oxford. Friedman, along with Martin Brazeau, authored a commentary about the new fish for Nature.
Friedman told Discovery News that some fossil jawless fishes "had broad, shovel-shaped heads with their eyes placed on top, while others had narrow bodies and skulls with their eyes on either side of the head."
Both Friedman and study co-author Brian Choo said that a handful of jawless fishes -- the eel-like lampreys and hagfishes -- are still alive today.