Image: Sauropod
GNS Science  /  AFP/Getty Images
Tooth analysis suggests that sauropods migrated widely to satisfy their gargantuan appetites.
By
updated 10/26/2011 2:30:36 PM ET 2011-10-26T18:30:36

What did giant plant-munching dinosaurs do when they couldn't find enough to eat in the parched American West? They hit the road.

An analysis of fossilized teeth adds further evidence that the long-necked dinosaurs called sauropods — the largest land creatures — went on road trips to fill their gargantuan appetites.

Scientists have long theorized that sauropods foraged for precious resources during droughts because of their preserved tracks and long limbs that were "ideal moving machines" and allowed them to cover long distances, said paleobiologist Matthew Bonnan of Western Illinois University.

  1. Science news from NBCNews.com
    1. NOAA
      Cosmic rays may spark Earth's lightning

      All lightning on Earth may have its roots in space, new research suggests.

    2. How our brains can track a 100 mph pitch
    3. Moth found to have ultrasonic hearing
    4. Quantum network could secure Internet

The latest study is the best evidence yet that at least one kind of sauropod "took to the hills in search of food when times got tough in the lowlands," said paleontologist Kristi Curry Rogers at Macalester College in Minnesota.

The new work, published online Wednesday by the journal Nature, was led by geologist Henry Fricke of Colorado College.

The researchers analyzed 32 sauropod teeth collected in Wyoming and Utah. The teeth came from massive plant-eaters that roamed a semi-arid basin in the American West during the late Jurassic period about 150 million years ago.

Scientists can get a glimpse into the source of the dinosaurs' drinking water by comparing the oxygen preserved in the tooth enamel to that found in ancient sediment.

Image: Dinosaur teeth
Henry Fricke  /  Colorado College via AP
A sampling of dinosaur teeth from the Dinosaur National Monument in Utah. Scientists analyzing 32 teeth of plant-eating dinosaurs found that they migrated from the lowlands to highlands in search of food and water during the late Jurassic period.

A chemical analysis showed differences in the teeth and the basin where the dinosaurs were buried, meaning they must have wandered hundreds of miles from the flood plains to the highlands for food and water.

Fricke said the movement appeared to be tied to changing seasons. Sauropods left the basin in the summer for higher elevations — a trek that took about five months — and returned in the winter.

In lush times, sauropods would have feasted on a diversity of plants including ferns, horsetails, conifers and moss, said John Foster, a curator at the Museum of Western Colorado, who had no part in the research.

Copyright 2011 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Data: The rise and fall of Earth's species

Explainer: The world's seven deadliest dinosaurs

  • Copyright 1985 Mark Hallett, "Awakening of Hunger"

    Yeah, it's cliche to say Tyrannosaurus rex was deadly. But the tyrant king was likely true to the billing. Its bone-crushing jaws could splinter prey like toothpicks, after all. And the beast was big, up to 40 feet long, 20 feet tall, and may have topped the scales at nearly 16,000 pounds.

    The king walked on two legs over a vast territory in western North America at the end of the Cretaceous, about 65 million years ago. Scientists wonder whether T. rex was more a lumbering scavenger or a quick and agile predator, but dead or alive, its meals were big, meaty and bloody.

    T. rex wasn't the only deadly dino, however. The globe was filled vicious killers. Click the arrows above to see more.

    — John Roach, msnbc.com contributor

  • Family diner

    Demetrios M. Vital

    Family meals for Majungasaurus crenatissimus were often bloody affairs of the grimmest sort: Kin were the main course. The evidence of its cannibalistic ways comes from telltale tooth marks on Majungasaurus bones that match up perfectly with the size and spacing of teeth in its jaws.

    The 20-foot-long dinosaur stalked the plains of Madagascar about 70 million years ago. At that time, the crime-scene investigators said, pickings were often slim. Their data indicate Majungasaurus fed on dried out "dino jerky" from its plant-eating compatriots as well as members of its own species. Cannibalism was likely just as common among dinosaurs as it is among living animals, but the evidence is rare.

  • Brow beater

    Todd Marshall

    Eocarcharia dinops' brow was swollen into a massive band of bone. The menacing head piece may have been used as a battering ram against rivals and to attract potential mates. Its blade-shape teeth were reserved for disabling live prey and severing their body parts.

    The 110-million-year-old beast and its snout-nosed, gut-and-carcass-scavenging relative Kryptops palaios were discovered in Africa's Sahara Desert. The approximately 7-foot-tall and 25-foot-long duo likely teamed up with a third carnivore and feasted on the long-necked plant-eater Nigersaurus.

  • Vicious rocker

    Parsons

    The toothy Masiakasaurus knopfleri likely speared prey with its forward projecting front teeth and then sliced and tore the captives into chewy chunks with its bladelike rears. This type of tooth arrangement is otherwise unknown in predatory dinosaurs.

    Scientists believe the German Shepherd sized beast feasted on fish, lizards, and other critters on the southern supercontinent Gondwana in the Late Cretaceous period, about 65 to 70 million years ago.

    The first part of this dinosaur's name means "vicious lizard" and the second part is derived from the Dire Straits singer and guitarist Mark Knopfler, whose music inspired the discoverers as they toiled on the African island nation of Madagascar.

  • Biggest carnivore?

    Prof. Rodolfo Coria / Ap

    At about 40 feet long and weighing an estimated 6 tons, Mapusaurus roseae was one of the biggest meat-eating dinosaurs to ever stalk the Earth. Bones of several individuals were discovered in one place, suggesting the giants may have hunted in packs that could have toppled perhaps the largest dinosaur that ever lived — a 100-foot-long plant eater called Argentinosaurus.

    Mapusaurus lived about 100 million years ago and was bigger than well known Tyrannosaurus rex and possibly larger than its older cousin, Gigantosaurus. Its teeth were narrow and blade like, made for slicing its prey. The bones were discovered in the Patagonia region of Argentina.

  • Going green

    MWS

    Falcarius utahensis is the living image of a vicious meat eater trying to go vegetarian. Scientists aren't sure if the bird-like relative of Velociraptor had fully kicked its taste for flesh, but its meat-cutting teeth had shrunk to leaf-cutting size and its gut had expanded sufficiently to ferment plants.

    Falcarius walked on two legs and stood about 4.5 feet tall. Head to tail, it was about 13 feet long and wielded sharp, curved, four-inch long claws — perhaps to grab a bite when it fell off the wagon? The dinosaur lived during the Early Cretaceous, about 125 million years ago, in what is today Utah.

  • Plant ripper

    utah.edu

    No plants were safe from Gryposaurus monumentensis, a big boned, duck-billed dinosaur that could have eaten any vegetation it stumbled across. Its massive skull packed more than 300 teeth for slicing up fibrous greens. Hundreds more replacement teeth rested in its jawbone for the call-up to action.

    The dinosaur lived in the Late Cretaceous, about 75 million years ago on the western side of a giant, shallow ocean that split North America at that time. The plant-munching beast may have reached 30 feet long as an adult and had a 3-foot-long head.

Discuss:

Discussion comments

,

Most active discussions

  1. votes comments
  2. votes comments
  3. votes comments
  4. votes comments