Navigation Links
Tell-tale toes point to oldest-known fossil bird tracks from Australia
Date:10/28/2013

Two fossilized footprints found at Dinosaur Cove in Victoria, Australia, were likely made by birds during the Early Cretaceous, making them the oldest known bird tracks in Australia.

The journal Palaeontology is publishing an analysis of the footprints led by Anthony Martin, a paleontologist at Emory University in Atlanta who specializes in trace fossils, which include tracks, burrows and nests. The study was co-authored by Patricia Vickers-Rich and Michael Hall of Monash University in Victoria and Thomas Rich of the Museum Victoria in Melbourne.

Much of the rocky coastal strata of Dinosaur Cove in southern Victoria were formed in river valleys in a polar climate during the Early Cretaceous. A great rift valley formed as the ancient supercontinent Gondwana broke up and Australia separated from Antarctica.

"These tracks are evidence that we had sizeable, flying birds living alongside other kinds of dinosaurs on these polar, river floodplains, about 105 million years ago," Martin says.

The thin-toed tracks in fluvial sandstone were likely made by two individual birds that were about the size of a great egret or a small heron, Martin says. Rear-pointing toes helped distinguish the tracks as avian, as opposed to a third nearby fossil track that was discovered at the same time, made by a non-avian theropod.

A long drag mark on one of the two bird tracks particularly interested Martin.

"I immediately knew what it was a flight landing track because I've seen many similar tracks made by egrets and herons on the sandy beaches of Georgia," Martin says.

Martin often leads student field trips to Georgia's coast and barrier islands, where he studies modern-day tracks and other life traces, to help him better identify fossil traces.

The ancient landing track from Australia "has a beautiful skid mark from the back toe dragging in the sand, likely caused as the bird was flapping its wings and coming in for a soft landing," Martin says. Fossils of landing tracks are rare, he adds, and could add to our understanding of the evolution of flight.

Today's birds are actually modern-day dinosaurs, and share many characteristics with non-avian dinosaurs that went extinct, such as nesting and burrowing. (Martin previously discovered the trace fossils of non-avian dinosaur burrows, including at a site along the coast of Victoria.)

The theropod carnivore Tyrannosaurus rex had a vestigial rear toe, evidence that T. rex shared a common ancestor with birds. "In some dinosaur lineages, that rear toe got longer instead of shorter and made a great adaptation for perching up in trees," Martin says. "Tracks and other trace fossils offer clues to how non-avian dinosaurs and birds evolved and started occupying different ecological niches."

Dinosaur Cove has yielded a rich trove of non-avian dinosaur bones from dozens of species, but only one skeletal piece of a bird a fossilized wishbone has been found in the Cretaceous rocks of Victoria.

Martin spotted the first known dinosaur trackway of Victoria in 2010 and a few other tracks have been discovered since then. Volunteers working in Dinosaur Cove found these latest tracks on a slab of rock, and Martin later analyzed them.

The tracks were made on the moist sand of a river bank, perhaps following a polar winter, after spring and summer flood waters had subsided, Martin says. "The biggest question for me," he adds, "is whether the birds that made these tracks lived at the site during the polar winter, or migrated there during the spring and summer."

One of the best records of the dinosaur-bird connection has come from discoveries in Liaoning province of Northeastern China, including fossils of non-avian dinosaurs with feathers. Samples of amber have also been found in Liaoning, containing preserved feathers from both birds and non-avian dinosaurs going back to the Cretaceous.

"In contrast, the picture of early bird evolution in the Southern Hemisphere is mostly incomplete," Martin says, "but with these tracks, it just got a little better."


'/>"/>

Contact: Beverly Clark
beverly.clark@emory.edu
404-712-8780
Emory Health Sciences
Source:Eurekalert  

Related biology news :

1. Penn research points to new way of preserving fertility for boys undergoing cancer treatment
2. Newly discovered foot points to a new kid on the hominin block
3. Researchers pinpoint genetic pathway of rare facial malformation in children
4. Culturally sensitive research in United Arab Emirates pinpoints indoor air quality risks
5. Discovered a new checkpoint of cell cycle control through joint action of 2 proteins
6. Its in the genes: Research pinpoints how plants know when to flower
7. Computer model pinpoints prime materials for efficient carbon capture
8. 3-V Biosciences Appoints Douglas I. Buckley, PhD, as Vice President of Biology
9. Shrinking leaves point to climate change
10. Conatus Pharmaceuticals Appoints Mark F. Morris as Head of Biostatistics
11. Study points to causes of high dolphin deaths in Gulf of Mexico
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Tell-tale toes point to oldest-known fossil bird tracks from Australia
(Date:4/11/2017)... April 11, 2017 NXT-ID, Inc. (NASDAQ: ... company, announces the appointment of independent Directors Mr. Robin ... its Board of Directors, furthering the company,s corporate governance and ... Gino Pereira ... look forward to their guidance and benefiting from their considerable ...
(Date:4/4/2017)... --  EyeLock LLC , a leader of iris-based identity ... and Trademark Office (USPTO) has issued U.S. Patent No. ... iris image with a face image acquired in sequence ... th issued patent. "The issuance ... multi-modal biometric capabilities that have recently come to market ...
(Date:3/29/2017)... , March 29, 2017  higi, the health IT ... North America , today announced a ... the acquisition of EveryMove. The new investment and acquisition ... of tools to transform population health activities through the ... data. higi collects and secures data today ...
Breaking Biology News(10 mins):
(Date:10/9/2017)... ... 09, 2017 , ... The Giving Tree Wellness Center announces ... needs of consumers who are incorporating medical marijuana into their wellness and health ... As operators of two successful Valley dispensaries, The Giving Tree’s two founders, Lilach ...
(Date:10/7/2017)... (PRWEB) , ... October 06, ... ... years’ experience providing advanced instruments and applications consulting for microscopy and surface ... expertise in application consulting, Nanoscience Analytical offers a broad range of contract ...
(Date:10/7/2017)... 6, 2017  The 2017 Nobel Prize in ... Jacques Dubochet, Joachim Frank and ... cryo-electron microscopy (cryo-EM) have helped to broaden ... biology community. The winners worked with systems manufactured ... produce highly resolved, three-dimensional images of protein structures ...
(Date:10/6/2017)... ... 06, 2017 , ... On Tuesday, October 24th, ABC² (Accelerate ... first-ever adaptive clinical trial for glioblastoma (GBM). The featured speaker will be Dr. ... open to the public, but registration is required. , WHAT: ABC² Brain ...
Breaking Biology Technology: