Dinosaur Neck Decoded

By Ellen Kuwana
Neuroscience for Kids Staff Writer
December 4, 2004

Scientists who study dinosaur remains are called paleontologists (from "pali" meaning ancient, "onta" meaning existing things, and "logy" meaning the study of). They examine fossil remains to figure out how life existed in the past.

By comparing fossils to skeletons of modern-day animals, scientists can make educated guesses about the lives of dinosaurs. Careful study of the nasal area, for example, led a scientist in 2001 to declare that drawings of dinosaur noses (Diplodocus) placed the nostril in the wrong place.

This fall, another group of researchers published their theory about why one type of dinosaur skeleton found in southern China had a really loooooooong neck. Dinocephalosaurus orientalis (which translates as "terrible-headed lizard from the Orient") had a neck about twice as long as its torso. The neck of this dinosaur measured 1.7 meters (~5.6 feet); its torso was 1 meter (~3.3 feet). The neck was supported by 25 vertebrae with "neck ribs" running among them. This contributed to a more rigid neck, not a snake-like neck, as assumed previously. The scientist wanted to know why this creature, which lived 230 million years ago, had such a long neck compared to its body.

The dinosaur's short limbs and muscle attachments to the foot bones (similar to those of sea turtles) suggested to scientists that this animal lived in water. Why would a long neck be helpful in water? How would a big, heavy creature catch something to eat in water? The long neck would allow the dinosaur to spot and catch prey without moving its bulky body. Movement in the water creates pressure waves, which alert prey that a threat is lurking nearby.

And what of the neck ribs? The dinosaur researchers propose that these small bones helped the neck to change shape slightly. This change would widen the esophagus, the tube down which food travels from the mouth to the stomach. As the esophagus widened, a suction force would be created to suck prey in. At the same time, pressure waves that push prey away from the dino's mouth would be counteracted. Fish and some turtles use suction to help capture their meals, but this is the first time that such a feeding strategy has been proposed for a dinosaur.

Hear IT!
Paleontology Dinocephalosaurus Esophagus Vertebrae

Did You Know?

  • Giraffes have seven neck vertebrae -- the same as humans!
  • Tyrannosaurus rex weighed 5-7 tons; the African elephant weighs 5 tons.
  • A stegosaurus dinosaur weighed approximately 1,600 kg but had a brain that weighed only approximately 70 grams (0.07 kg). Therefore, the brain was only 0.004% of its total body weight. In contrast, an adult human weighs approximately 70 kg and has a brain that weighs approximately 1.4 kg. Therefore, the human brain is about 2% of the total body weight. This makes the brain to body ratio of the human 500 times greater than that of the stegosaurus.

References and Further Information:

  1. >Big Gulp? Neck ribs may have given aquatic beast unique feeding style. Science News, September 25, 2004.
  2. Did Triassic Monster Use Suction to Feed? BioEd Online, September 23, 2004.
  3. Ancient Sea Creatures Sucked in Prey, New Scientist, September 23, 2004.
  4. Li C., Rieppel O. & LaBarbera M., A triassic aquatic protorosaur with an extremely long neck, Science, 305:1931, 2004.

GO TO: Neuroscience In The News Explore the Nervous System Table of Contents

Send E-mail

Fill out survey

Get Newsletter

Search Pages

Take Notes