Navigation Links
Finding an answer to Darwin's Dilemma

The sudden appearance of large animal fossils more than 500 million years ago ?a problem that perplexed even Charles Darwin and is commonly known as "Darwin’s Dilemma" ?may be due to a huge increase of oxygen in the world’s oceans, says Queen’s paleontologist Guy Narbonne, an expert in the early evolution of animals and their ecosystems.

In 2002, Dr. Narbonne and his research team found the world’s oldest complex life forms between layers of sandstone on the southeastern coast of Newfoundland. This pushed back the age of Earth’s earliest known complex life to more than 575 million years ago, soon after the melting of the massive "snowball" glaciers. New findings reported today shed light on why, after three billion years of mostly single-celled evolution, these large animals suddenly appeared in the fossil record.

In a paper published on-line in Science Express, Dr. Narbonne’s team argues that a huge increase in oxygen following the Gaskiers Glaciation 580 million years ago corresponds with the first appearance of large animal fossils on the Avalon Peninsula in Newfoundland.

Now for the first time, geochemical studies have determined the oxygen levels in the world’s oceans at the time these sediments accumulated in Avalon. "Our studies show that the oldest sediments on the Avalon Peninsula, which completely lack animal fossils, were deposited during a time when there was little or no free oxygen in the world’s oceans," says Dr. Narbonne. "Immediately after this ice age there is evidence for a huge increase in atmospheric oxygen to at least 15 per cent of modern levels, and these sediments also contain evidence of the oldest large animal fossils."

Also on the research team are Don Canfield (University of Southern Denmark) and Simon Poulton (Newcastle University, U.K.). Geochemical studies by Drs. Canfield and Poulton included measurements of iron speciation and sulphur isotopes to determine the oxygen levels in the world’s oce
'"/>

Source:Queen's University


Page: 1 2

Related biology news :

1. Finding Cures For Tropical Diseases: Is Open Source An Answer?
2. Fundamental Finding Yields Insight into Stem Cells, Cancer; Opens Door to Drug Discovery
3. Findings have implications for tracking disease, drugs at the molecular level
4. Finding hidden invaders in a Hawaiian rain forest
5. New Finding May Aid Adult Stem Cell Collection
6. Finding rewrites the evolutionary history of the origin of potatoes
7. Finding the minds eye
8. Findings advance use of adult stem cells for replacement bone
9. Finding a virus is not all bad news
10. Finding a better way to make biodiesel
11. Finding paves way for better treatment of autoimmune disease
Post Your Comments:
*Name:
*Comment:
*Email:
TAG: Finding answer Darwin Dilemma

(Date:8/25/2014)... COLUMBIA, Mo. A family of proteins that promotes ... block the release of HIV and other viruses, University ... surprising finding that provides new insights into our understanding ... Ebola and other viruses," said Shan-Lu Liu, M.D., Ph.D., ... of Molecular Microbiology and Immunology. , The study was ...
(Date:8/25/2014)... reproduces by manipulating the behavior of ants emits ... brain of its natural target host, but not ... shows., The findings, which suggest that the fungus ... the molecular mechanisms underlying this phenomenon, according to ... to secrete chemicals that affect their environment," noted ...
(Date:8/25/2014)... 25, 2014 Riddell, the leader in football ... Research Institute (TGen), a leader in cutting-edge genomic ... University and its Sun Devil football program will ... to advance athlete concussion detection and treatment. , ... project will combine molecular information and head impact ...
Breaking Biology News(10 mins):MU researchers discover protein's ability to inhibit HIV release 2MU researchers discover protein's ability to inhibit HIV release 3Zombie ant fungi 'know' brains of their hosts 2Zombie ant fungi 'know' brains of their hosts 3Riddell, TGen team with ASU football to further genetic research into concussion detection 2Riddell, TGen team with ASU football to further genetic research into concussion detection 3
... won the American Geophysical Unions 2008 journalism awards: ... Excellence in Science JournalismNews for her article on the biggest ... shelf suspected to be a victim of global warming. ... daily newspaper in Montreal, Quebec, Canada. ...
... According to a report released today by the Wildlife ... Cambodias famed Tonle Sap region have staged remarkable comebacks, ... park rangers to provide 24-hour protection to breeding colonies. ... and egg collectors to protect and monitor the colonies, ...
... at North Carolina State University have pinpointed a small group ... to produce a hormone that is key to their development. ... production in plants affects both a plants growth and its ... assistant professor of genetics, and a team of geneticists and ...
Cached Biology News:AGU Journalism Awards won by Margaret Munro and Dr. Richard Smith 2NC State researchers identify genes key to hormone production in plants 2
(Date:8/26/2014)... 26, 2014   Lycera Corp ., a ... medicines to treat autoimmune disease and cancer based ... the appointment of Harinder Singh , Ph.D., ... Dr. Singh will lead the board,s efforts to ... ongoing research programs and pipeline of therapies targeting ...
(Date:8/26/2014)... Genedata, a leading provider of ... science research, today announced the Genedata Screener® ... in Asia, Europe, and North America during September ... leading research organizations will gather for annual User ... and upcoming challenges in all areas of screening. ...
(Date:8/26/2014)... , Aug. 26, 2014  That,s Nice LLC, a ... today announced the formation of a new dedicated team ... The expanded team will combine current and new staff ... That,s Nice. Guy Tiene ... lead the team. Tiene was previously Director of Marketing ...
(Date:8/26/2014)... Formedix, the leading provider of clinical ... Transform for MARVIN: the latest addition to its ... line. It was developed in collaboration with Formedix ... the EDC and Clinical Data Management system. , ... allowing instantaneous visualization of MARVIN eCRFs as they ...
Breaking Biology Technology:Lycera Appoints Harinder Singh, Ph.D., as Chair of Scientific Advisory Board 2Lycera Appoints Harinder Singh, Ph.D., as Chair of Scientific Advisory Board 3Thought Leaders to Explore Innovations in SPR & Combination Screening at Genedata Screener User Group Meetings 2Thought Leaders to Explore Innovations in SPR & Combination Screening at Genedata Screener User Group Meetings 3That's Nice Announces Expanded Offering For Strategic Content And Public Relations 2That's Nice Announces Expanded Offering For Strategic Content And Public Relations 3Introducing Transform for MARVIN: Providing Further Flexibility for CROs and Sponsors in Partnership with XClinical 2
... in Physics from the Public University of Navarre and ... studied the behaviour and properties of nanometric-scale semiconductor crystals. ... Dr Echeverra to study the behaviour of semiconductor crystals ... hundred nanometres (a nanometre is a millionth part of ...
... 15 In a continual effort to alleviate the ... Nursing,s Future is hosting the Promise of Nursing ... scholarships to help ease the nursing shortage in Pennsylvania. ... in Philadelphia on Thursday, September 16, will support regional ...
... Sept. 14 Dendreon Corporation (Nasdaq: DNDN ) ... of North American commercial operations at Genentech, a wholly-owned member ... of Directors. "It,s been rewarding to serve ... in Dendreon,s history," said Mr. Clark. "Unfortunately, my job responsibilities ...
Cached Biology Technology:Ph.D. study of behavior of semiconductor crystals of size less than 100 nanometers 2Pennsylvania Partnerships Address Statewide Nursing Shortage 2Pennsylvania Partnerships Address Statewide Nursing Shortage 3Dendreon Announces Change in Board of Directors 2
... universal digital valve, just 8 mm in width. ... features in a single glass-reinforced, PBT (Polybutylene Terephthalate) ... in width. , Meets a range of pressure ... , Satisfies a 0.016 sccm leakage specification (0.2 ...
... The FilterMate is a compact, versatile system ... a 96- or 24-well microplates into a ... microplate liquid scintillation and gamma counter. The ... samples for applications such as cell proliferation, ...
... General description: Designed for use with ... CLS number is a new product number, ... If showing no availability yet, please order ... contact customer service for assistance. Comp Dim: ...
... G bind specifically to Fc regions of ... G conjugates are commonly used as affinity ... subtypes from serum, hybridoma ascites fluids, tissue ... reagents are also commonly used to capture ...
Biology Products: