Welcome To Website IAS

Hot news
Achievement

Independence Award

- First Rank - Second Rank - Third Rank

Labour Award

- First Rank - Second Rank -Third Rank

National Award

 - Study on food stuff for animal(2005)

 - Study on rice breeding for export and domestic consumption(2005)

VIFOTEC Award

- Hybrid Maize by Single Cross V2002 (2003)

- Tomato Grafting to Manage Ralstonia Disease(2005)

- Cassava variety KM140(2010)

Centres
Website links
Vietnamese calendar
Library
Visitors summary
 Curently online :  54
 Total visitors :  7664832

Temporal variation of planetary iron as a driver of evolution
Sunday, 2022/01/02 | 08:51:06

Jon Wade et al.; PNAS December 21, 2021 118 (51) e2109865118

 

Iron is an irreplaceable component of proteins and enzyme systems required for life. This need for iron is a well-characterized evolutionary mechanism for genetic selection. However, there is limited consideration of how iron bioavailability, initially determined by planetary accretion but fluctuating considerably at global scale over geological time frames, has shaped the biosphere. We describe influences of iron on planetary habitability from formation events >4 Gya and initiation of biochemistry from geochemistry through oxygenation of the atmosphere to current host–pathogen dynamics. By determining the iron and transition element distribution within the terrestrial planets, planetary core formation is a constraint on both the crustal composition and the longevity of surface water, hence a planet’s habitability. As such, stellar compositions, combined with metallic core-mass fraction, may be an observable characteristic of exoplanets that relates to their ability to support life. On Earth, the stepwise rise of atmospheric oxygen effectively removed gigatons of soluble ferrous iron from habitats, generating evolutionary pressures. Phagocytic, infectious, and symbiotic behaviors, dating from around the Great Oxygenation Event, refocused iron acquisition onto biotic sources, while eukaryotic multicellularity allows iron recycling within an organism. These developments allow life to more efficiently utilize a scarce but vital nutrient. Initiation of terrestrial life benefitted from the biochemical properties of abundant mantle/crustal iron, but the subsequent loss of iron bioavailability may have been an equally important driver of compensatory diversity. This latter concept may have relevance for the predicted future increase in iron deficiency across the food chain caused by elevated atmospheric CO2.

 

See: https://www.pnas.org/content/118/51/e2109865118

 

Fig. 1. The iron content of terrestrial bodies of approximate Mars size reflects the mean redox conditions of core formation (oxygen fugacity, fO2, shown relative to the iron-wüstite [FeO] buffer). A Mars-like planet forming under conditions around 10× more oxidizing than the Earth possesses a mantle in excess of double the FeO content. In contrast, a Mercury-like planet forming under conditions ∼100× more reducing leaves its mantle denuded in FeO (<0.5 Earth) and also, a host of other transition elements (Cr < 0.5 Earth, Ni ∼ 0.1 Earth, Mo ∼ 0.01 Earth). The arrow represents the upper limit of Mercury’s mantle FeO content (14). The model follows ref. 75 and assumes all planets are of Mars mass, with metallic cores fully equilibrating with the mantle at depths of ∼1/3 of the growing mantle; further details are given in SI Appendix.

Back      Print      View: 219

[ Other News ]___________________________________________________
  • Egypt Holds Workshop on New Biotech Applications
  • UN Agencies Urge Transformation of Food Systems
  • Taiwan strongly supports management of brown planthopper—a major threat to rice production
  • IRRI Director General enjoins ASEAN states to invest in science for global food security
  • Rabies: Educate, vaccinate and eliminate
  • “As a wife I will help, manage, and love”: The value of qualitative research in understanding land tenure and gender in Ghana
  • CIP Director General Wells Reflects on CIP’s 45th Anniversary
  • Setting the record straight on oil palm and peat in SE Asia
  • Why insect pests love monocultures, and how plant diversity could change that
  • Researchers Modify Yeast to Show How Plants Respond to Auxin
  • GM Maize MIR162 Harvested in Large Scale Field Trial in Vinh Phuc, Vietnam
  • Conference Tackles Legal Obligations and Compensation on Biosafety Regulations in Vietnam
  • Iloilo Stakeholders Informed about New Biosafety Regulations in PH
  • Global wheat and rice harvests poised to set new record
  • GM Maize Harvested in Vietnam Field Trial Sites
  • New label for mountain products puts premium on biological and cultural diversity
  • The Nobel Prize in Physiology or Medicine 2016
  • Shalabh Dixit: The link between rice genes and rice farmers
  • People need affordable food, but prices must provide decent livelihoods for small-scale family farmers
  • GM Seeds Market Growth to Increase through 2020 Due to Rise in Biofuels Use

 

Designed & Powered by WEBSO CO.,LTD