Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Dinosaur extinction occurred at peak of diversity

18.11.2004


Research refutes long-held belief that diversity was declining



When dinosaurs became extinct from the effects of a massive asteroid hitting Earth 65 million years ago, there were more varieties of the reptiles living than ever before, according to a new analysis of global fossil records by a team of researchers led by a University of Rhode Island paleontologist. "Our analysis finally lays to rest the old, utterly unsupported idea that dinosaurs were declining in diversity during the last 10 million years of their time on Earth," said David Fastovsky, URI professor of geosciences.

Fastovsky’s analysis, published in the October issue of Geology, found that early dinosaurs from the late Triassic period comprised only 40 known genera, but diversity dramatically increased throughout the time dinosaurs were on Earth, skyrocketing in the Cretaceous period -- 99 to 65 million years ago -- when at least 245 dinosaur genera lived. "Dinosaur diversity was increasing logarithmically throughout their 160 million years on Earth," said Fastovsky, who is conducting research at the National Autonomous University of Mexico through July 2005 as a Fulbright Scholar. "Their increasing diversity seems to have been fueled by the evolution of new innovations that allowed them to explore new habitat."


According to Fastovsky and his co-authors, early dinosaurs tended to be unspecialized, but during the late Cretaceous period they became much more specialized in their feeding and behavior patterns, driving their evolution into more and more genera. The diversity of plant-eating dinosaurs in the Cretaceous was found to be especially high. "The ability to colonize heretofore unavailable ecospace by the invention of new feeding mechanisms and behaviors may have been a key driving force in the striking and continuous Jurassic-Cretaceous dinosaur diversification," the researchers wrote in Geology.

Earlier studies, based almost entirely on North American dinosaur records, suggested a drop in dinosaur diversity in the 10 million years leading up to their extinction. Fastovsky’s conclusions are drawn from his analysis of a new database of global dinosaur records, which shows that much of the diversity of dinosaur genera is found in fossils unearthed in Asia and South America.

Fastovsky also believes that searching for more dinosaur fossils -- though there are likely many more to be found -- will shed little new light on this subject. Instead, he said his analysis suggests that "a more useful approach to understanding the dynamics of their evolution would be to more precisely date the ones that we already know about."

Todd McLeish | EurekAlert!
Further information:
http://www.uri.edu

More articles from Earth Sciences:

nachricht Ice cave in Transylvania yields window into region's past
28.04.2017 | National Science Foundation

nachricht Citizen science campaign to aid disaster response
28.04.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>