WASHINGTON -- An Ohio researcher is proposing a nose job for the dinosaur. He believes the fleshy nostrils of the huge animals were at the front of their long snouts, not back nearer the eyes as experts have assumed for more than a century.
"The nose is a remarkable multipurpose organ," said Lawrence M. Witmer, a dinosaur researcher at the College of Osteopathic Medicine at Ohio University. "It is involved in a whole range of physiological functions.... It just makes more sense" for it to be at the tip of the snout, just above the mouth.
Witmer, author of a study appearing Friday in the journal Science, said that since the 1800s dinosaur scientists have assumed that the noses of the extinct animals were up just below the eyes. This was where the nasal passage dips into the skull, and most experts assumed the outside opening to this breathing airway would be nearby.
Since the tissue and cartilage of a nose are too soft to fossilize and never have been part of recovered dinosaur remains studied by scientists, said Witmer, researchers made an educated guess about where the dino nose belonged.
After some of the first dinosaur fossils were found in the late 19th century, he said, "experts thought they were so large that these animals couldn't have supported themselves on land and had to be aquatic so the water would support their bulk."
Since they lived in water, the reasoning went, and since the nasal opening in the skull was near the top of the head, then the nose must have been there, too.
"It seemed reasonable that it (the nose) would serve as a kind of snorkel," Witmer said.
Later, scientists realized the huge dinosaurs were perfectly capable of living on land, he said. "But we never thought about the nose again," Witmer said. "We left it on top of the head and never moved it."
Witmer is now proposing that the dino nose in pictures and models be moved to where he thinks nature actually put it, on the end of the snout.
The researcher said he studied the noses of all of the major modern animals groups, including close relatives of the dinosaur such as the crocodile, and found that nearly always the nose is on the very front of the face. People and animals, he said, led with the nose, the better to smell the air for food, friend and foe.
Witmer also closely examined the bony skulls of many dinosaur specimens. On the long snouts, he found channels and tunnels that suggested the presence of delicate nasal passages filled with nerves and blood vessels and covered with cartilage and flesh.
"Muscles will produce scars and blood vessels, and nerves will make grooves," he said. The only reasonable explanation, said Witmer, is that dinosaurs had fine, long noses that extended in a fleshy tunnel from the nasal passageway into the skull down to the nostrils just above the mouth.
That is the most common type of nose in modern animals, said Witmer, and it seems most likely that dinosaurs would have the same arrangement.
If he is right, Witmer said, the airway for many of the larger dinosaurs was six to eight inches longer than previously believed. This could be important to the animal because a long nose does important things, he said.
"When we think of a nose we think of this thing that our glasses perch on," he said.
But noses aren't made only to support specs or to smell the roses, he said.
The moist airway of a nose filters and conditions air as an animal breathes. Warm air is cooled and cold air heated by the nose. Witmer said a nose can even condense some moisture from the air, helping an animal preserve fluids, which is important in arid regions. The longer the nose, the more effective it performs these functions, he said.
"This is a solid piece of work," Paul Sereno, a University of Chicago dinosaur expert, said of the Witmer study.
Sereno said when he and others reconstruct dinosaurs from bony fossils, there is always a problem of where to put fleshy openings, such as the nose. Putting the nose farther front, he said, makes sense.
"With the nose at the front, you would not only enhance the sense of smell, but you would also put air flow over this fleshy surface, and that would have some benefits," such as warming and humidifying the air, Sereno said.
