Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New fossil sheds light on old mystery

24.09.2004


Scientists from IVPP, Field Museum and University of Chicago describe a new Chinese reptile from the Triassic and propose a unique feeding method



The well-preserved fossil of a newly discovered reptile species may explain the function of the extremely long neck for which some protorosaurs are known – a feature that has puzzled scientists for decades. The Protorosauria is an order of diverse predatory reptiles that lived as far back as 280 million years ago. Scientists have never been able to figure out the function of the extremely long neck that characterizes some species of this group, including Tanystropheus longobardicus, which was discovered in the 1850s.

About twice as long as its trunk, Tanystropheus’ neck has 12 vertebrae along which extend elongated cervical ribs. Years ago, scientists concluded that the long, stiff neck was more or less a consequence of growth patterns rather than a specific functional adaptation. The new species of protorosaur, however, provides additional clues and suggests that the long neck in these animals may have been part of a unique and very effective method for capturing prey in water.


Dinocephalosaurus orientalis, which means "terrible-headed lizard from the Orient," was recently discovered in southern China. It has a neck made up of 25 vertebrae, again with elongated cervical ribs extending along them. In an embargoed article to be published in Science on September 24, 2004, the authors describe how the neck may have been used to capture prey.

"This is important research because we have finally explained the functional purpose of this strange, long neck," said Olivier Rieppel, PhD, a co-author of the Science paper and chair of geology and curator of fossil amphibians and reptiles at Chicago’s Field Museum. "It allowed an almost perfect strike at prey, which usually consisted of elusive fish and squid."

Prey in water is slippery, and any movement toward it not only alerts the prey of an attack but also creates a pressure wave that could push the prey away. Fish and some turtles combat these factors with suction feeding, i.e., pulling the prey into their months by rapidly expanding the mouth cavity.

Crocodiles and alligators use a different approach. They catch prey with their flat head and pincer jaws, which allow them (when feeding in water) to strike laterally, cutting through the water while minimizing the force that pushes the prey away.

Dinocephalosaurus apparently took yet another approach. When it thrust its head forward to capture prey, the ribs along its neck would splay outward. This would increase the diameter of the esophagus, creating a suction force that would swallow the pressure wave created by the lunging head, along with the prey.

"The unusual neck morphology of Dinocephalosaurus would have allowed it to suction feed, a feeding mode previously unknown for fossil aquatic reptiles," said Michael LaBarbera, PhD, professor of organismal biology and anatomy at the University of Chicago. "But suction feeding in Dinocephalosaurus was different from suction feeding in any other animal. Rather than expand the volume of its mouth to suck in prey, Dinocephalosaurus expanded the volume of its throat, in many ways a more effective approach."

In addition, the long neck allowed Dinocephalosaurus to draw near its prey stealthily so it would have less of a chance of being detected. "To a fish in murky water, Dinocephalosaurus’ head would have initially looked like another animal its own size, but by the time the fish was able to see Dinocephalosaurus’ body, it would already have been lunch," Dr. LaBarbera said.

"Dinocephalosaurus sheds new light on the evolution of protorosaurs and the functional morphology of these long-necked marine reptiles," said Chun Li, lead author and assistant research fellow at the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences in Beijing.

"When Tanystropheus, the first long-necked protorosaur to be found, was discovered in Europe in the 1850s it raised so many questions that it was called a ’biomechanical nightmare,’ " Chun added. "And it generated fiery discussion among scientists as recently as the 1980s." Dinocephalosaurus is 230 million years old and dates from the Triassic. It has 25 cervical vertebrae to Tanystropheus’ 12, which might have made its neck a little more flexible. "These two species are not very closely related, which demonstrates that this strange, long neck evolved twice within the group of protorosaurs," Dr. Rieppel said.

Dinocephalosaurus’ neck measures 1.7 meters, while its trunk is less than 1 meter long. Some of its cervical ribs, which are connected to neck vertebrae, span several intervertebral joints. The ribs increase in length from the front of the neck to the back of the neck, bridging more joints near the base of the neck than near the head. Unlike most protorosaurs, Dinocephalosaurus was fully aquatic, although it might have laid its eggs on land.

Greg Borzo | EurekAlert!
Further information:
http://www.fieldmuseum.org
http://www.uchospitals.edu

More articles from Life Sciences:

nachricht Transport of molecular motors into cilia
28.03.2017 | Aarhus University

nachricht Asian dust providing key nutrients for California's giant sequoias
28.03.2017 | University of California - Riverside

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Transport of molecular motors into cilia

28.03.2017 | Life Sciences

A novel hybrid UAV that may change the way people operate drones

28.03.2017 | Information Technology

NASA spacecraft investigate clues in radiation belts

28.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>