PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Fossil skull sheds new light on transition from water to land

2015-03-11
(Press-News.org) 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.

INFORMATION:

The study is published today 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.



ELSE PRESS RELEASES FROM THIS DATE:

Length matters

2015-03-11
Mutations in the methyl CpG binding protein 2 gene (MECP2) are the cause of the devastating childhood neurological disorder Rett Syndrome. Despite intense efforts spanning several decades the precise function of MECP2 has been difficult to pin down. Research primarily funded by the Rett Syndrome Research Trust (RSRT) and the National Institutes of Neurological Disease and Stroke (NINDS), and published today in the journal Nature reveals important information that could lead to new treatment approaches. The study, led by Michael Greenberg, Ph.D., Chairman of the Department ...

Therapeutic exercise lessens lung injury and muscle wasting in critically ill patients

2015-03-11
WINSTON-SALEM, N.C. - March 11, 2015 - Acute respiratory distress syndrome (ARDS) is a life-threatening lung condition that affects approximately 200,000 people a year in the United States and has a higher mortality rate than breast and prostate cancer combined. The condition most often occurs in people who are critically ill or who have significant injuries; those who do survive it often experience profound skeletal muscle weakness. Over the past 30 years, efforts to fight ARDS with various drug therapies aimed at the lungs have failed. However, doctors at Wake Forest ...

Is US immigration policy 'STEMming' innovation?

2015-03-11
(Santa Barbara, Calif.) - Foreign born graduate students in STEM (science, technology, engineering and math) disciplines who wish to pursue a career in industry or NGOs are much more likely to stay in the U.S. than those who wish to pursue a career in academia or government concludes a study by researchers at UC Santa Barbara's Center for Nanotechnology in Society. Published on March 11, 2015 in the open access journal PLOS ONE, the study provides new insight into why foreign-born graduate students in STEM fields choose to remain in the United States or return to their ...

Prescription for living longer: Spend less time alone

2015-03-11
Ask people what it takes to live a long life, and they'll say things like exercise, take Omega-3s, and see your doctor regularly. Now research from Brigham Young University shows that loneliness and social isolation are just as much a threat to longevity as obesity. "The effect of this is comparable to obesity, something that public health takes very seriously," said Julianne Holt-Lunstad, the lead study author. "We need to start taking our social relationships more seriously." Loneliness and social isolation can look very different. For example, someone may be surrounded ...

Rat brains point to lead's role in schizophrenia

2015-03-11
A study of the brains of rats exposed to lead has uncovered striking similarities with what is known about the brains of human schizophrenia patients, adding compelling evidence that lead is a factor in the onset of schizophrenia. Results of the study by scientists at Columbia University's Mailman School of Public Health appear in the journal Translational Psychiatry. The researchers found that lead had a detrimental effect on cells in three brain areas implicated in schizophrenia: the medial prefrontal cortex, the hippocampus, and the striatum of rats exposed to lead ...

Georgia State study: Ebola-infected sewage may require longer holding period

2015-03-11
Storing Ebola-infected sewage for a week at 86° Fahrenheit or higher should allow enough time for more than 99.99 percent of the virus to die, though lower ambient temperatures may require a longer holding period, according to a new study by researchers at Georgia State University's School of Public Health. The study co-authored by Lisa M. Casanova, assistant professor of environmental health, and Scott R. Weaver, research assistant professor in Epidemiology and Biostatistics, used bacteriophage Φ6, a type of virus, as a stand-in to study how long Ebola and similar ...

Analysis suggests a more virulent swine flu virus in the Indian subcontinent

2015-03-11
A flu outbreak in India that has claimed over 1200 lives may not be identical to the 2009 North American strain, as recently reported in India. A comparative analysis conducted by scientists at the Massachusetts Institute of Technology (MIT) shows that the flu virus in India seems to have acquired mutations that could spread more readily and therefore requires deeper studies. As flu season in India winds down, the researchers call on officials to increase surveillance of this and future flu outbreaks and rethink vaccination strategies to account for potential new viruses. ...

A sea change for ocean resource management

2015-03-11
SAN DIEGO, Calif. (March 11, 2015)-- Ocean ecosystems around the world are threatened by overfishing, extensive shipping routes, energy exploration, pollution and other consequences of ocean-based industry. Data exist that could help protect these vulnerable ecosystems, but current management strategies often can't react quickly enough to new information, said San Diego State University biologist Rebecca Lewison. She and colleagues from several other academic, governmental and non-governmental organizations endorse a new approach called "dynamic ocean management" in a ...

Study shows even injured kidneys can be used for transplants

2015-03-11
New Haven, Conn. -- Kidneys from deceased donors that have acute injuries are frequently discarded instead of being used for transplant. However, a Yale-led study finds that such kidneys may be more viable than previously thought, and should be considered to meet the growing demand for organ transplants. Donated kidneys with acute injury are often discarded for fear of poor outcomes such as delayed function and even premature kidney transplant failure. Given the growing need for transplant organs, the Yale-led team embarked on the largest multicenter observational study ...

Swine flu outbreak in India raises concern

2015-03-11
CAMBRIDGE, MA -- Since December, an outbreak of swine flu in India has killed more than 1,200 people, and a new MIT study suggests that the strain has acquired mutations that make it more dangerous than previously circulating strains of H1N1 influenza. The findings, which appear in the March 11 issue of Cell Host & Microbe, contradict previous reports from Indian health officials that the strain has not changed from the version of H1N1 that emerged in 2009 and has been circulating around the world ever since. With very little scientific data available about the new ...

LAST 30 PRESS RELEASES:

A third of licensed GPs in England not working in NHS general practice

ChatGPT “thought on the fly” when put through Ancient Greek maths puzzle

Engineers uncover why tiny particles form clusters in turbulent air

GLP-1RA drugs dramatically reduce death and cardiovascular risk in psoriasis patients

Psoriasis linked to increased risk of vision-threatening eye disease, study finds

Reprogramming obesity: New drug from Italian biotech aims to treat the underlying causes of obesity

Type 2 diabetes may accelerate development of multiple chronic diseases, particularly in the early stages, UK Biobank study suggests

Resistance training may improve nerve health, slow aging process, study shows

Common and inexpensive medicine halves the risk of recurrence in patients with colorectal cancer

SwRI-built instruments to monitor, provide advanced warning of space weather events

Breakthrough advances sodium-based battery design

New targeted radiation therapy shows near-complete response in rare sarcoma patients

Does physical frailty contribute to dementia?

Soccer headers and brain health: Study finds changes within folds of the brain

Decoding plants’ language of light

UNC Greensboro study finds ticks carrying Lyme disease moving into western NC

New implant restores blood pressure balance after spinal cord injury

New York City's medical specialist advantage may be an illusion, new NYU Tandon research shows

Could a local anesthetic that doesn’t impair motor function be within reach?

1 in 8 Italian cetacean strandings show evidence of fishery interactions, with bottlenose and striped dolphins most commonly affected, according to analysis across four decades of data and more than 5

In the wild, chimpanzees likely ingest the equivalent of several alcoholic drinks every day

Warming of 2°C intensifies Arctic carbon sink but weakens Alpine sink, study finds

Bronze and Iron Age cultures in the Middle East were committed to wine production

Indian adolescents are mostly starting their periods at an earlier age than 25 years ago

Temporary medical centers in Gaza known as "Medical Points" (MPs) treat an average of 117 people daily with only about 7 staff per MP

Rates of alcohol-induced deaths among the general population nearly doubled from 1999 to 2024

PLOS One study: In adolescent lab animals exposed to cocaine, High-Intensity Interval Training boosts aversion to the drug

Scientists identify four ways our bodies respond to COVID-19 vaccines

Stronger together: A new fusion protein boosts cancer immunotherapy

Hidden brain waves as triggers for post-seizure wandering

[Press-News.org] Fossil skull sheds new light on transition from water to land