Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Relatives of Living Ducks and Chickens Existed Alongside Dinosaurs More Than 65 Million Years Ago

21.01.2005


A reconstruction by well-known dinosaur artist Michael Skrepnick shows Vegavis in the immediate foreground with a duckbill dinosaur (hadrosaur) in the background. Copyright Michael Skrepnick 2005.


One half of the Vegavis iaai specimen (left) and the volumetric rendering from the computed tomography (CT) data (right).


Newly published North Carolina State University research into the evolution of birds shows the first definitive fossil proof linking close relatives of living birds to a time when dinosaurs roamed the earth.

Research by paleontologist Dr. Julia A. Clarke, an assistant professor in the marine, earth and atmospheric sciences department at NC State, and colleagues provides unprecedented fossil proof that some close cousins to living bird species coexisted with dinosaurs more than 65 million years ago. Information from a new avian species called Vegavis iaai indicates that these birds lived in the Cretaceous period and must have survived the Cretaceous/Tertiary (K/T) mass extinction event that included the disappearance of all other dinosaurs.

Analysis of fresh evidence from computed tomography (CT) scans of the fossil – which uncovered new bones deep within the rock matrix – and recovery of latex peels made of the specimen just after its discovery in Antarctica in 1992 revealed its importance to avian evolution and that it represented a new species. This partial skeleton is the most complete specimen from the Cretaceous to be found to have its evolutionary relationship to a living bird group. These new data show Vegavis is within the group Anseriformes, which includes ducks and geese.



The research is published in the Jan. 20 edition of the scientific journal Nature.

The question of whether relatives of living birds existed alongside non-bird dinosaurs has evoked intense recent controversy in scientific circles. Some scholars, arguing from some “molecular clock” models and new DNA sequence data as well as the distribution of living bird groups, have concluded that relatives of living birds must have existed alongside non-avian dinosaurs and survived the mass extinction of dinosaurs at the K/T boundary, about 65 million years ago. Until the discovery of Vegavis, fossil data to support this hypothesis was weak at best.

Other scientists have claimed this limited previous data was unreliable and that the fossil record showed no evidence of living bird lineages in the Cretaceous. In a “big bang” theory of bird evolution, these scientists have proposed that relatives of today’s birds came on the scene only after non-avian dinosaurs became extinct at the K/T boundary.

“We have more data than ever to propose at least the beginnings of the radiation of all living birds in the Cretaceous,” Clarke says. “We now know that duck and chicken relatives coexisted with non-avian dinosaurs. This does not mean that today’s chicken and duck species lived with non-avian dinosaurs, but that the evolutionary lineages leading to today’s duck and chicken species did.”

The fossil’s fragility – the specimen was damaged as it was being prepared for study – led to difficulties in conducting a full examination in 1992. Earlier this year, Clarke received a grant from the National Science Foundation to give the fossil – named for the location it was discovered (Vega Island in western Antarctica) and for the name of the party that made the discovery (the Instituto Antártico Argentino, or IAA) – a second look with a team of colleagues from Argentina and the United States.

Clarke and her fellow scientists conducted new analyses on the fragile partial skeleton. CT scans were performed on the fossil for the first time; these X-rays uncovered new bones in the rock matrix, including a number of vertebrae, pelvic bones, and arm and leg bones. The researchers also found the original latex peels – applied to the fossil before any other preparation had been done – that provided a mirror image of the bones originally exposed on the rock surface.

The newly discovered bones and latex peels allowed the scientists to compare features of Vegavis to other birds and determine its evolutionary relationships. Clarke and her colleagues used some of the largest data sets available and all placed Vegavis within the radiation of living birds – as most closely related to ducks and geese. Histological analysis of the bone tissues present in a cross section of a Vegavis arm bone not only indicates that Vegavis was an adult at the time of death but also supports inference of its evolutionary relationships from the independent phylogenetic results.

The data place Vegavis within Aves, which includes common ancestors of all living birds we have today and all its descendents – that is, the radiation of all living birds – and specifically within one group of Aves called Anseriformes, the waterfowl, which includes ducks, geese and allies. Within this group Vegavis is positioned close to the lineage leading to true ducks and geese, called Anatidae.

Clarke will now continue her search for more clues to the evolution of birds. “Looking to the Cretaceous for more parts of extant avian radiation is essential,” she says.

Funding for the research came from an NSF Office of Polar Programs Small Grant for Experimental Research.

Dr. Julia Clarke | EurekAlert!
Further information:
http://www.ncsu.edu

More articles from Earth Sciences:

nachricht Fossil coral reefs show sea level rose in bursts during last warming
19.10.2017 | Rice University

nachricht NASA finds newly formed tropical storm lan over open waters
17.10.2017 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Electrode materials from the microwave oven

19.10.2017 | Materials Sciences

New material for digital memories of the future

19.10.2017 | Materials Sciences

Physics boosts artificial intelligence methods

19.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>