HOME >> BIOLOGY >> NEWS
Despite their heft, many dinosaurs had surprisingly tiny genomes

CAMBRIDGE, Mass. -- They might be giants, but many dinosaurs apparently had genomes no larger than that of a modern hummingbird.

So say scientists who've linked bone cell and genome size among living species and then used that new understanding to gauge the genome sizes of 31 species of extinct dinosaurs and birds, whose bone cells can be measured from the fossil record.

The researchers, at Harvard University and the University of Reading, were led by Chris Organ and Scott V. Edwards, both at Harvard. They report their findings this week in the journal Nature.

"We see distinct differences between two major lineages of dinosaurs," says Organ, a postdoctoral fellow in organismic and evolutionary biology supported by the National Institutes of Health. "The theropods -- carnivores such as Tyrannosaurus rex and Velociraptor -- had very small genomes, in the range of modern birds. Ornithischians -- which include Stegosaurus and Triceratops -- had more moderately sized genomes, akin to those of living lizards and crocodilians. We aren't sure about the genomes of the long-necked sauropods yet."

Organ and Edwards say the clear-cut dichotomy in dinosaur genomes is likely due to different amounts of repetitive and non-coding DNA in the two groups' genetic material, a factor largely responsible for variation in genome size across animal species. They estimate that active repetitive DNA might have comprised an average 12 percent of the ornithischian genome but just 8.4 percent of theropod genetic constitution.

The work indicates that the small genomes typically associated with birds -- whose genetic composition is noticeably sparer than that of other vertebrates -- evolved in dinosaurs some 230 to 250 million years ago, rather than with the emergence of modern living birds just 110 million years ago. Organ and Edwards suggest after this shrinking, theropod genomes then stabilized in size for hundreds of millions of years, a pr
'"/>

Contact: Steve Bradt
steve_bradt@harvard.edu
617-496-8070
Harvard University
7-Mar-2007


Page: 1 2

Related biology news :

1. Despite acidity, orange juice could still be a source of foodborne disease
2. Despite causes of lupus proving complex, critical checkpoint suggesting new therapy is revealed
3. ESF EURYI award winner aims to stop cancer cells reading their own DNA
4. How cells change the pace of their steps
5. Unlocking proteins from their cellular shell
6. Cells take risks with their identities
7. Birds take cues from their competitors
8. St. Jude study shows genes play an unexpected role in their own activation
9. Pre-cancerous blood diseases can be products of their environment
10. Plants recognize their siblings, biologists discover
11. Daddies girls choose men just like their fathers

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:7/31/2020)... ... July 30, 2020 , ... BioFactura, Inc. today ... by the Joint Science & Technology Office—Chemical and Biological Defense (JSTO-CBD) of the ... and scale-up a highly efficient mammalian cell culture-based bioprocess suitable to meet surge ...
(Date:7/18/2020)... (PRWEB) , ... July 16, 2020 , ... ... that demonstrates the effectiveness of the Invictus Medical Neoasis™ active noise control device ... The study reported that the Neoasis™ device attenuated the alarm sounds from patient ...
(Date:7/10/2020)... CHICAGO (PRWEB) , ... July 09, 2020 , ... Today ... Umami Advantage, which will share insight on the “fifth taste” phenomenon that is revolutionizing ... snacks. The Umami Advantage will be live on Monday, July 13, 2020 at11:00 AM ...
Breaking Biology News(10 mins):
(Date:8/3/2020)... ... 2020 , ... Introducing Ardent Animal Health – MediVet Biologics rebrands company and ... Known as MediVet Biologics since its formation in 2016, the company is relaunching itself ... will build on its base of innovative therapies for osteoarthritis and cancer. ...
(Date:7/31/2020)... , ... July 29, 2020 , ... ... can combine up to three different materials for use with CRM, neurostimulation, vascular, ... to three materials to meet specific design requirements, performance, and cost criteria; especially ...
(Date:7/31/2020)... (PRWEB) , ... July 30, ... ... of cloud-based software for the life sciences industry, today announced the release ... platform designed specifically for Medical Science Liaisons (MSLs) and other field medical ...
(Date:7/18/2020)... ... July 16, 2020 , ... ... the early detection and prevention of high-burden diseases, and Centric Consulting, a business ... healthcare organizations to utilize existing data in order to identify and prioritize patients ...
Breaking Biology Technology:
Cached News: