Subscribe free to our newsletters via your
. GPS News .




EARLY EARTH
Fossil skull sheds new light on transition from water to land
by Staff Writers
Bristol, UK (SPX) Mar 12, 2015


The original fossil skull of Acanthostega gunnari. Image courtesy Dr Laura Porro.

The first 3D reconstruction of the skull of a 360 million-year-old near-ancestor of land vertebrates has been created by scientists from the Universities of Bristol and Cambridge, UK. The 3D skull, which differs from earlier 2D reconstructions, suggests such creatures, which lived their lives primarily in shallow water environments, were more like modern crocodiles than previously thought.

The researchers applied high-resolution X-ray computed tomography (CT) scanning to several specimens of Acanthostega gunnari, one of the 'four-footed' vertebrates known as tetrapods which invaded the land during one of the great evolutionary transitions in Earth's history, 380-360 million years ago. Tetrapods evolved from lobe-finned fishes and display a number of adaptations to help them survive on land.

An iconic fossil species, Acanthostega gunnari is crucial for understanding the anatomy and ecology of the earliest tetrapods. However, after hundreds of millions of years in the ground fossils are often damaged and deformed. No single specimen of Acanthostega preserves a skull that is complete and three-dimensional which has limited scientists' understanding of how this key animal fed and breathed - until now.

Using special software, the Bristol and Cambridge researchers 'digitally prepared' a number of Acanthostega specimens from East Greenland, stripping away layers of rock to reveal the underlying bones.

They uncovered a number of bones deep within the skull, including some that had never before been seen or described, resulting in a detailed anatomical description of the Acanthostega skull.

Once all of the bones and teeth were digitally separated from each other, cracks were repaired and missing elements duplicated. Bones could then be manipulated individually in 3D space. Using information from other specimens, the bones were fitted together like puzzle pieces to produce the first 3D reconstruction of the skull of Acanthostega, with surprising results.

Lead author, Dr Laura Porro, formerly of Bristol's School of Earth Sciences and now at the Royal Veterinary College, said: "Because early tetrapods skulls are often 'pancaked' during the fossilization process, these animals are usually reconstructed having very flat heads. Our new reconstruction suggests the skull of Acanthostega was taller and somewhat narrower than previously interpreted, more similar to the skull of a modern crocodile."

The researchers also found clues to how Acanthostega fed. The size and distribution of its teeth and the shape of contacts between individual bones of the skull (called sutures) suggest Acanthostega may have initially seized prey at the front of its jaws using its large front teeth and hook-shaped lower jaw.

Co-author, Professor Emily Rayfield, also from Bristol's School of Earth Sciences, said: "These new analyses provide fresh clues about the evolution of the jaws and feeding system as the earliest animals with limbs and digits began to conquer the land."

The researchers plan to apply these methods to other flattened fossils of the earliest tetrapods to better understand how these early animals modified their bones and teeth to meet the challenges of living on land.

Digital models of the original fossils and the 3D reconstruction are also useful in scientific research and education. They can be accessed by researchers around the world, without risking damage to fragile original fossils and without scientists having to travel thousands of miles to see original specimens. Furthermore, digital models and 3D printouts can be easily and safely handled by students taking courses and by the public during outreach events.

The study was published in PLOS ONE. Paper: 'Descriptive anatomy and three-dimensional reconstruction of the skull of the early tetrapod Acanthostega gunnari Jarvik, 1952' by Laura B. Porro, Emily J. Rayfield and Jennifer A. Clack in PLOS ONE.


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only


.


Related Links
University of Bristol
Explore The Early Earth at TerraDaily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





EARLY EARTH
Young stegosaurus weighed 3,527 pounds
London (UPI) Mar 4, 2015
Scientists have estimated the weight of young stegosaurus specimen recently acquired by the London's Natural History Museum. Still only a juvenile when it died, the plated dino weighed an incredible 3,527 pounds. The stegosaurus specimen, nicknamed Sophie, boasts 80 percent of its bones - the most complete and well-preserved skeleton of its kind. "Because this incredible specime ... read more


EARLY EARTH
Dartmouth-led team identifies circadian clock gene that strengthens crop plant

Chinese cyber-dissident takes farmers' land fight online

Early herders' grassy route through Africa

Protecting crops from radiation-contaminated soil

EARLY EARTH
Quantum sensor's advantages survive entanglement breakdown

The taming of magnetic vortices

Important step towards quantum computing: Metals at atomic scale

QR codes with advanced imaging and photon encryption protect computer chips

EARLY EARTH
No known link between towelette found in Australia and MH370

MH370 report sparks fresh criticism of Malaysia govt, airline

Airlines need to improve despite 'safest' year: IATA chief

New vision system on way for military helicopter pilots

EARLY EARTH
Making our highways safer and more efficient

Understanding electric car 'range anxiety' could be key to wider acceptance

Car industry welcomes Google, Apple but battles loom

Uber discloses data breach, theft of license numbers

EARLY EARTH
China February trade surplus hits record $60.6 bn: govt

WTO to help settle Canadian trade rows with China, Taiwan

Scientists question rush to build Nicaragua canal

Amazon sets up shop in China on Alibaba platform

EARLY EARTH
The green lungs of our planet are changing

Amazon deforestation 'threshold' causes species loss to accelerate

Landless Brazilians in GM eucalyptus protest

Direct evidence that drought-weakened Amazonian forests 'inhale less carbon'

EARLY EARTH
Scientists report breakthrough in detecting methane

High-Tech UCF Sensor Payload Headed for Stratosphere

Space technology investigates large-scale changes to Africa's climate

A change in thought on Earth's core formation

EARLY EARTH
Magnetic vortices in nanodisks reveal information

Researchers turn unzipped nanotubes into possible alternative for platinum

Black phosphorus a new wonder material for optical communication

New nanowire structure absorbs light efficiently




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.