 |
|
Massive dinosaur discovered in Antarctica sheds light on life, distribution of sauropodomorphs
December 11, 2007Only second Jurassic dinosaur ever found in Antarctica
CHICAGO-A new genus and species of dinosaur from the Early Jurassic has been discovered in Antarctica. The massive plant-eating primitive sauropodomorph is called Glacialisaurus hammeri and lived about 190 million years ago.
The recently published description of the new dinosaur is based on partial foot, leg and ankle bones found on Mt. Kirkpatrick near the Beardmore Glacier in Antarctica at an elevation of more than 13,000 feet.
"The fossils were painstakingly removed from the ice and rock using jackhammers, rock saws and chisels under extremely difficult conditions over the course of two field seasons," said Nathan Smith, a graduate student at The Field Museum. "They are important because they help to establish that primitive sauropodomorph dinosaurs were more broadly distributed than previously thought, and that they coexisted with their cousins, the true sauropods."
The findings were published online Dec. 5 in the Acta Palaeontologica Poloncica (see http://www.app.pan.pl/). Diego Pol, a paleontologist at the Museo Paleontológico Egidio Feruglio in Chubut, Argentina, is the other co-author of the research.
Sauropodomorph dinosaurs were the largest animals to ever walk the earth. They were long-necked herbivores and include Diplodocus and Apatosaurus. Their sister group is the theropods, which include Tyrannosaurus, Velociraptor, and modern birds.
Glacialisaurus hammeri was about 20-25 feet long and weighed about 4-6 tons . It was named after Dr. William Hammer, a professor at Augustana College who led the two field trips to Antarctica that uncovered the fossils. Glacialisaurus belongs to the sauropodomorph family Massopsondylidae, which may represent a secondary radiation of basal sauropodomorphs during the Early Jurassic.
Currently, the development and evolutionary relationships of the sauropodomorph dinosaurs are hotly debated by paleontologists. This discovery, however, helps to resolve some of this debate by establishing two things. First, it shows that sauropodomorphs were widely distributed in the Early Jurassic-not only in China, South Africa, South America and North America, but also in Antarctica.
"This was probably due to the fact that major connections between the continents still existed at that time, and because climates were more equitable across latitudes than they are today," Smith said.
Second, the discovery of Glacialisaurus hammeri shows that primitive sauropodomorphs probably coexisted with true sauropods for an extended period of time. The recent discovery of a possible sauropod at roughly the same location in Antarctica lends additional evidence to the theory that the earliest sauropods coexisted with their basal sauropodomorph cousins, including Glacialisaurus hammeri, during the Late Triassic and Early Jurassic, Smith and Pol conclude in their research findings.
Field Museum
"The fossils were painstakingly removed from the ice and rock using jackhammers, rock saws and chisels under extremely difficult conditions over the course of two field seasons," said Nathan Smith, a graduate student at The Field Museum. "They are important because they help to establish that primitive sauropodomorph dinosaurs were more broadly distributed than previously thought, and that they coexisted with their cousins, the true sauropods."
The findings were published online Dec. 5 in the Acta Palaeontologica Poloncica (see http://www.app.pan.pl/). Diego Pol, a paleontologist at the Museo Paleontológico Egidio Feruglio in Chubut, Argentina, is the other co-author of the research.
Sauropodomorph dinosaurs were the largest animals to ever walk the earth. They were long-necked herbivores and include Diplodocus and Apatosaurus. Their sister group is the theropods, which include Tyrannosaurus, Velociraptor, and modern birds.
Glacialisaurus hammeri was about 20-25 feet long and weighed about 4-6 tons . It was named after Dr. William Hammer, a professor at Augustana College who led the two field trips to Antarctica that uncovered the fossils. Glacialisaurus belongs to the sauropodomorph family Massopsondylidae, which may represent a secondary radiation of basal sauropodomorphs during the Early Jurassic.
Currently, the development and evolutionary relationships of the sauropodomorph dinosaurs are hotly debated by paleontologists. This discovery, however, helps to resolve some of this debate by establishing two things. First, it shows that sauropodomorphs were widely distributed in the Early Jurassic-not only in China, South Africa, South America and North America, but also in Antarctica.
"This was probably due to the fact that major connections between the continents still existed at that time, and because climates were more equitable across latitudes than they are today," Smith said.
Second, the discovery of Glacialisaurus hammeri shows that primitive sauropodomorphs probably coexisted with true sauropods for an extended period of time. The recent discovery of a possible sauropod at roughly the same location in Antarctica lends additional evidence to the theory that the earliest sauropods coexisted with their basal sauropodomorph cousins, including Glacialisaurus hammeri, during the Late Triassic and Early Jurassic, Smith and Pol conclude in their research findings.
Field Museum
Earliest embryos ever discovered provide clues to dinosaur evolution, parenting
The embryos of a long-necked, herbivorous dinosaur are the earliest ever recorded for any terrestrial vertebrate and point to how primitive dinosaurs evolved into the largest animals ever to walk on earth.
More Sauropodomorph Current Events and Sauropodomorph News Articles
 |
Thunder-Lizards: The Sauropodomorph Dinosaurs (Life of the Past) by Virginia Tidwell (Editor), Kenneth Carpenter (Editor) The large, quadrupedal herbivores known as sauropods were widespread around the planet from the Jurassic to the end of the Cretaceous. With the longest necks and tails of all of the dinosaurs, some sauropods were 40 meters in length and weighed upwards of 100,000 kilograms, more than 20 tons. The popular image of these lumbering giants, placidly consuming ferns has been greatly revised in recent years. New discoveries and new theories about behavior and physiology have continued to enrich the study of these remarkable beasts. This book presents 21 new studies of the sauropods. The book is organized into four parts. The first part looks at some sauropods old and new, the second at juvenile and adult specimens and ontogenetic variation within species. Part three concerns morphology and... |
 |
Ultimate Dinosaur Book by David Lambert (Author) Profiles of specimens from every dinosaur group, illustrated with pictures of models and anatomy, offer the paleontological insights into dinosaur posture and gait, musculature and internal organs, behavior, and the reasons for extinction. 40,000 first printing. |
 |
Special Papers in Palaeontology, Evolution and Palaeobiology of Early Sauropodomorph Dinosaurs (No. 77) by Paul M. Barrett (Editor), David J. Batten (Editor) Special Papers in Palaeontology, published by The Palaeontological Association, is a series of substantial separate works conforming to the style of the Palaeontology journal. Two issues are published each year and feature high standard illustrations. An analysis of Sauropoda which includes many of the most familiar dinosaurs, such as Apatosaurus (formerly ‘Brontosaurus’), Diplodocus and Brachiosaurus (the latter finding fame in the Jurassic Park movies) Advances our knowledge of sauropod phylogeny, biomechanics, physiology and ecology and offers insights into the limits of life at large body size An active and constructive debate in dinosaur studies that will serve as a benchmark for future work on prosauropods and basal sauropods Includes 107 text-figures and 24... |
|
Anchisaurus Polyzelus (Hitchcock): The Smallest Known Sauropod Dinosaur and the Evolution of Gigantism Among Sauropodomorph Dinosaurs (Postilla) by Adam M. Yates (Author) | |
|
Thunder-Lizards: The Sauropodomorph Dinosaurs by Virginia Tidwell; Kenneth Carpenter (Author) |
| © 2009 BrightSurf.com |