Navigation Links
First animals oxygenated the ocean, study suggests
Date:3/9/2014

The evolution of the first animals may have oxygenated the earth's oceans contrary to the traditional view that a rise in oxygen triggered their development.

New research led by the University of Exeter contests the long held belief that oxygenation of the atmosphere and oceans was a pre-requisite for the evolution of complex life forms.

The study, published today in the leading journal Nature Geoscience, builds on the recent work of scientists in Denmark who found that sponges the first animals to evolve require only small amounts of oxygen.

Professor Tim Lenton of the University of Exeter, who led the new study, said: "There had been enough oxygen in ocean surface waters for over 1.5 billion years before the first animals evolved, but the dark depths of the ocean remained devoid of oxygen. We argue that the evolution of the first animals could have played a key role in the widespread oxygenation of the deep oceans. This in turn may have facilitated the evolution of more complex, mobile animals."

The researchers considered mechanisms by which the deep ocean could have been oxygenated during the Neoproterozoic Era (from 1,000 to 542 million years ago) without requiring an increase in atmospheric oxygen.

Crucial to determining oxygen levels in the deep ocean is the balance of oxygen supply and demand. Demand for oxygen is created by the sinking of dead organic material into the deep ocean. The new study argues that the first animals reduced this supply of organic matter both directly and indirectly.

Sponges feed by pumping water through their bodies, filtering out tiny particles of organic matter from the water, and thus helping oxygenate the shelf seas that they live in. This naturally selects for larger phytoplankton the tiny plants of the ocean which sink faster, also reducing oxygen demand in the water.

By oxygenating more of the bottom waters of shelf seas, the first filter-feeding animals inadvertently increased the removal of the essential nutrient phosphorus in the ocean. This in turn reduced the productivity of the whole ocean ecosystem, suppressing oxygen demand and thus oxygenating the deep ocean.

A more oxygen-rich ocean created ideal conditions for more mobile animals to evolve, because they have a higher requirement for oxygen. These included the first predatory animals with guts that started to eat one another, marking the beginning of a modern marine biosphere, with the type of food webs we are familiar with today.

Professor Lenton added: "The effects we predict suggest that the first animals, far from being a passive response to rising atmospheric oxygen, were the active agents that oxygenated the ocean around 600 million years ago. They created a world in which more complex animals could evolve, including our very distant ancestors."

Professor Simon Poulton of the University of Leeds, who is a co-author of the study, added: ″This study provides a plausible mechanism for ocean oxygenation without the requirement for a rise in atmospheric oxygen. It therefore questions whether the long-standing belief that there was a major rise in atmospheric oxygen at this time is correct. We simply don't know the answer to this at present, which is ultimately key to understanding how our planet evolved to its current habitable state. Geochemists need to come up with new ways to decipher oxygen levels on the early Earth.″


'/>"/>

Contact: Eleanor Gaskarth
e.f.gaskarth@exeter.ac.uk
44-782-730-9332
University of Exeter
Source:Eurekalert  

Related biology news :

1. Kessler Foundation implements Ekso Bionics first commercial robotic exoskeleton
2. Research reveals first evidence of hunting by prehistoric Ohioans
3. First model of how buds grow into leaves
4. American College of Rheumatology releases first classification criteria for polymyalagia rheumatica
5. Ottawa researchers to lead world-first clinical trial of stem cell therapy for septic shock
6. First complete full genetic map of promising energy crop
7. FirstMark Announces New Hire Jay Houtman as Southeast Regional Sales Manager
8. FirstMark Exhibiting at the Inaugural Atlanta Clinical Cardiology Update
9. New technology tracks sparrow migration for first time from California to Alaska
10. First mass extinction linked to marine anoxia
11. Scientists complete first-ever emperor penguin count from space
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
First animals oxygenated the ocean, study suggests
(Date:11/19/2016)... Securus Technologies, a leading provider of civil and criminal ... monitoring, announced today that it has offered a challenge ... technology judge determine who has the largest and best ... platform, and the best customer service. "ICSolutions ... we do – which clearly is not the case ...
(Date:11/15/2016)... 2016 Research and Markets has announced the ... report to their offering. ... The ... 2021 from USD 6.21 Billion in 2016, growing at a CAGR ... the bioinformatics market is driven by the growing demand for nucleic ...
(Date:6/22/2016)... 2016   Acuant , the leading ... has partnered with RightCrowd ® to ... Management, Self-Service Kiosks and Continuous Workforce Assurance. ... functional enhancements to existing physical access control ... with an automated ID verification and authentication ...
Breaking Biology News(10 mins):
(Date:11/30/2016)... 30, 2016 The global Pyrogen ... hold a dominant share in the overall market. The ... Inc., and Merck KGaA, held a lion,s share of ... Research observes that these companies are expected to retain ... that are do not require rabbit pyrogen testing along ...
(Date:11/30/2016)... Equicare Health Inc ., the leading supplier of comprehensive ... the top 100 companies in the 2016 Global Digital ... top digital health companies across the globe.   ... continually upgrading our product with the ongoing digital shift ... Len Grenier , CEO of Equicare Health, "It,s ...
(Date:11/30/2016)... Part of 5m$ Investment in Integrated Drug Discovery ... , ... announced that it had successfully completed the expansion of their ... the Screening Collection to over 400,000. The new compounds were ... company. This expansion, complemented by new robotics and compound management ...
(Date:11/30/2016)... , ... November 30, 2016 , ... ... the development of a new orally administered treatment for Alzheimer’s disease (AD), today ... of a Phase 2a clinical trial of T3D-959 in mild to moderate Alzheimer’s ...
Breaking Biology Technology: