card
268

Seismosaurus

OLogy Series
extinct animal
card
268

Seismosaurus

OLogy Series
extinct animal

Of all the dinosaurs to roam the Earth, the largest ones belonged to a group called sauropods- huge plant-eating dinosaurs with long necks and small heads. And of all the sauropods, the real giants were the diplodocids. One of the longest dinosaurs ever discovered was a diplodocid found in northern New Mexico. This giant, called Seismosaurus, grew to be over 120 feet long-almost half the length of a football field!

Clues to the Poopetrator
How do scientists know what-and how much- Seismosaurus ate? Some of the most important clues are the giant poops it left behind. Over time, animal poop, or dung, can fossilize. These remains are called coprolites (in Greek, kopros means "dung" and lithikos means "stone"). Coprolites are solid rock, but they contain important evidence that other
fossils do not. If a coprolite contains partially digested plant material, such as leaves, seeds, or bark, chances are it was made by an herbivore. And if a coprolite has fossilized bits of
bones, teeth, or muscle, the animal was probably a carnivore. These remains also provide information about the ecology of the animal's habitat. For example, if the coprolite contains the remains of a swamp-dwelling animal or plant, then the animal that produced the coprolite probably lived near a swamp.

The name Seismosaurus means:

dinosaur of great size

long-necked creature

earth-shaking lizard

Are you right?

Correct!

Of course, Seismosaurus isn’t a lizard at all-but it probably did shake the Earth! Walking on all four feet, its footstep must have echoed across the Jurassic landscape.

Scientists estimate that Seismosaurus weighed about 30 tons-about as much as:

8 Asian horses

8 African elephants

8 blue whales

Are you right?

Correct!

Seismosaurus weighed about as much as 8 African elephants. That may be huge, but it's not the largest animal that ever lived on Earth. That title belongs to the blue whale, which can weigh over 100 tons!

Sterling Nesbitt, Paleontologist

It's amazing how much you can tell from only a partial skeleton of a dinosaur. Seismosaurus is described based on the pelvis and parts of the tail!

Seismosaurus ate rocks as well as plants.

Fact
or
Fiction
?

Fact

Smooth, round stones have been found in its stomach cavity. It may have swallowed rocks to help digest its food, like chickens do today. It did ate hundreds of pounds of plants a day!

Seismosaurus was often prey for large meat-eating dinosaurs.

Fact
or
Fiction
?

Fiction

Seismosaurus was so huge, it was almost invulnerable-even to large carnivores.

Seismosaurus ("Earth-shaking lizard")
Locality found: New Mexico
Age: Late Jurassic, 145 mya
Size: over 120 feet long and 30 tons
Diet: plants
Characteristics: huge body, with a long neck, long tail, and four short legs; one of the longest dinosaurs ever found

Image credits: Sean Murtha; Sterling Nesbitt: courtesy of AMNH.