HOME >> BIOLOGY >> NEWS
Life in a greenhouse world

nt component of Earth's atmosphere occurred at the same time as analogous evidence for the first cyanobacteria?'"

Schwartzman and Caldeira followed up the proposal of Charles Dismukes and coworkers that now extinct bacteria were performing oxygen-based photosynthesis before cyanobacteria came onto the scene. In a CO2 dominated world, these early oxygenic photosynthesizers split bicarbonate instead of water as the source of oxygen. They apparently boosted organic productivity and caused greater methane production by methanogens living in the ocean.

"It takes far less methane to maintain climatic temperatures than it does carbon dioxide," says Schwartzman.

As methane became dominant, CO2 levels dropped dramatically. Cyanobacteria then emerged and began oxygenic photosynthesis by splitting water as the source of oxygen. According to Schwartzman, only when atmospheric oxygen levels began to rise some 2.2 billion years ago did a CO2-concentrating mechanism emerge, an adaptation to declining CO2/02 ratios in the external environment.

Thus, global constraints on evolution appeared to have included carbon dioxide as well as oxygen levels in the atmosphere along with surface temperature. All the former have been strongly influenced by biological evolution in a complex set of feedbacks, an essential aspect of biospheric evolution. "The classical paradigm of evolution, that changes in the local environment lead to natural selection, should be rethought to include these feedbacks on a global scale. We hope that our hypothesis will be tested by looking more closely at the extant geologic record of the proposed transition as well as the insights from the study of photosynthesis and molecular biology of modern organisms," says Schwartzman.


'"/>

Contact: Ann Cairns
acairns@geosociety.org
303-357-1056
Geological Society of America
25-Oct-2002


Page: 1 2

Related biology news :

1. Plants will not save us from greenhouse gases
2. Environmental decontamination, greenhouse gases, and the genome of a methane-loving bacterium
3. New space-borne instrument to track greenhouse gases, ozone destroyers, and other pollutants
4. Continents played key role in collapse and regeneration of Earths early greenhouse, geologists say
5. Improved crop production and fewer greenhouse gases
6. UGA researchers track greenhouse gases in forests
7. Scientists find key to ocean bacterium that helps control greenhouse gas
8. Plant diversity threatened by climate change and buildup of greenhouse gas, study reveals
9. Shifts in rice farming practices in China reduce greenhouse gas methane
10. Agricultural science helping farmers reduce greenhouse gas
11. Prospect of greenhouse gas reduction drives biofuels market

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:2/9/2016)... 2016 Aware, Inc. (NASDAQ: AWRE ), a leading ... its fourth quarter and year ended December 31, 2015.  ... quarter of 2015 was $6.9 million, an increase of 61% compared ... in the fourth quarter of 2015 was $2.6 million compared to ... --> --> Higher revenue and operating income ...
(Date:2/8/2016)... 2016 Worldcore is ... innovation for clients, comfort and unbeatable security, with ... --> Worldcore is the first EU-regulated ... comfort and unbeatable security, with a Voice Biometrics ... Worldcore is the first EU-regulated global payment ...
(Date:2/4/2016)... LONDON , Feb. 4, 2016 ... is apparently one of the most popular hubs ... Project, MetaHIT and other huge studies of human ... that past few years, the microbiome space has ... applied biomedical research. This report focuses on ...
Breaking Biology News(10 mins):
(Date:2/11/2016)... and GERMANTOWN, Maryland , February ... Prime Standard: QIA) today announced the introduction of more ... expression profiling, expanding QIAGEN,s portfolio of Sample to Insight ... to select from over 20,000 human genes and lncRNA ... genes, cellular phenotypes and disease processes. --> ...
(Date:2/11/2016)... , Feb. 11, 2016  Dovetail Genomics™ LLC today ... beta program for a planned metagenomic genome assembly service. ... company,s metagenomic genome assembly method in a talk on ... Biology & Technology conference in Orlando, Fla. ... highly complex datasets is difficult. Using its proprietary ...
(Date:2/11/2016)... (PRWEB) , ... February 11, 2016 , ... ... of its new stem cell treatment clinic in Quito, Ecuador. The new facility ... and trauma applications to patients from around the world. , The new ...
(Date:2/10/2016)... Feb.10, 2016 ASAE is introducing a hybrid ... Companies (AMC) the option of joining or renewing through ... determined by staff size, every employee in any size ... and reap all available member benefits.   ... organizational membership options will allow organizations of any size ...
Breaking Biology Technology:
Cached News: