Rise of dinosaurs in Late Triassic more gradual than once thought

Berkeley -- Fossils discovered in the oft-painted arroyos of northern New Mexico show for the first time that dinosaurs and their non-dinosaur ancestors lived side by side for tens of millions of years, disproving the notion that dinosaurs rapidly replaced their supposedly outmoded predecessors.

The fossils were excavated from the Hayden Quarry at Ghost Ranch, an area made famous through the paintings of Georgia O'Keefe, by a team of paleontologists from the University of California, Berkeley, the American Museum of Natural History and The Field Museum. The finds, including fossil bones of a new dinosaur predecessor the researchers have named Dromomeron romeri, are described in a cover story in the July 20 issue of Science.

"Up to now, paleontologists have thought that dinosaur precursors disappeared long before the dinosaurs appeared, that their ancestors probably were out-competed and replaced by dinosaurs and didn't survive," said co-author Kevin Padian, professor of integrative biology at UC Berkeley and a curator in the campus's Museum of Paleontology. "Now, the evidence shows that they may have coexisted for 15 or 20 million years or more."

According to primary authors Randall Irmis and Sterling Nesbitt, graduate students, respectively, at UC Berkeley and at New York's American Museum, the new bones provide anatomical information that tells paleontologists about the evolution of dinosaur precursors, their transition into true dinosaurs and how dinosaurs diversified.

"Finding dinosaur precursors, or basal dinosauromorphs, together with dinosaurs tells us something about the pace of changeover," Irmis said. "If there was any competition between the precursors and dinosaurs, then it was a very prolonged competition."

An alternative hypothesis held that the sudden extinction of many animals in the Late Triassic period allowed dinosaurs to diversify and eventually populate the globe. Based on the new findings, ho

Contact: Robert Sanders
University of California - Berkeley

Page: 1 2 3 4

Related biology news :

1. Despite their heft, many dinosaurs had surprisingly tiny genomes
2. Large dinosaurs were extremely hot in their day, UF study finds
3. Sensational find: The mini-dinosaurs from the Harz Mountains
4. Oceans may soon be more corrosive than when the dinosaurs died
5. Unexpected finding: Some dinosaurs grew slower in hard times
6. Latest study: Scientists say no evidence exists that therapod dinosaurs evolved into birds
7. Did feathered dinosaurs exist?
8. Study: Predatory dinosaurs had bird-like pulmonary system
9. Burnt coal from the age of dinosaurs sheds light on todays global warming
10. Killer dinosaurs turned vegetarian
11. Strains of laboratory mice more varied than previously thought

Post Your Comments:

(Date:11/18/2015)... , Nov. 18, 2015  As new scientific discoveries ... doctors and other healthcare providers face challenges in better ... and patients. In addition, as more children continue to ... patient,s adulthood and old age. John M. ... Children,s Hospital of Philadelphia (CHOP) . --> ...
(Date:11/17/2015)... November 17, 2015 Paris ... --> Paris from 17 th ... the biometrics innovation leader, has invented the first combined scanner ... the same scanning surface. Until now two different scanners were ... scanner can capture both on the same surface. This ...
(Date:11/17/2015)... 17, 2015  Vigilant Solutions announces today that Mr. ... of Directors. --> --> ... from the partnership at TPG Capital, one of the ... $140 Billion in revenue.  He founded and led TPG,s ... TPG companies, from 1997 to 2013.  In his first ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... CITY , Nov. 24, 2015 /PRNewswire/ - Aeterna ... request of IIROC on behalf of the Toronto Stock ... news release there are no corporate developments that would ... --> --> About ... www.aezsinc.com . --> Aeterna Zentaris is ...
(Date:11/24/2015)... , November 24, 2015 ... market research report "Oligonucleotide Synthesis Market by Product & ... Gene Synthesis, Diagnostic, DNA, RNAi), End-User (Research, Pharmaceutical & ... by MarketsandMarkets, the market is expected to reach USD ... 2015, at a CAGR of 10.1% during the forecast ...
(Date:11/24/2015)... , ... November 24, 2015 , ... The Academy of ... Interest Group (SIG), MultiGP, also known as Multirotor Grand Prix, to represent the First–Person ... few years. Many AMA members have embraced this type of racing and several new ...
(Date:11/24/2015)... New York , November 24, 2015 ... to a recent market research report released by Transparency ... projected to expand at a CAGR of 17.5% during ... "Non-invasive Prenatal Testing Market - Global Industry Analysis, Size, ... estimates the global non-invasive prenatal testing market to reach ...
Breaking Biology Technology:
Cached News: