The Living Earth: Our Home in the Solar System and the Universe

Abstract

This book investigates the billion-year takeover of planet Earth by its organisms and ecosystems. This takeover, which is unique in the Solar System, is explained by the existence of interactions between a small number of key environmental and biological mechanisms. Throughout the book, hidden relationships are identified among the suite of nested systems made of the ecosystems, the Earth System, the Solar System, and the Universe. This chapter considers successively five aspects of the Earth System in the context of the Solar System: the organisms, which are subject to biological evolution, and their key features; the Solar System, populated by billions of objects, which is the homeland of Earth in the Universe; Earth together with its sister planets and their moons; a brief history of the 13.7 billion-year Universe; and a brief history of 4.6 billion-year Earth. Several astronomical characteristics have hidden connections with organisms, such as: formation of key chemical elements in dying stars; long-term changes in Earth’s orbit (Milankovitch cycles) responsible for the succession of glacial and interglacial episodes since 2.6 million years; supply of water by asteroids and/or comets; characteristics of the Earth-Moon system favouring the long-term presence of liquid water. The chapter ends with a summary of key points concerning connections between organisms, Earth, the Solar System, and the whole Universe. The co-evolution of Earth and its organisms and ecosystems created the whole Earth system, called here the Living Earth. The latter was achieved 2.5 billion years before present, after two phases called Mineral Earth and Cradle Earth.

Figure Credits

Fig. 1.1 Original. Figure 1.1 is licensed under CC BY-SA 4.0 by Philippe Bertrand, Louis Legendre and Mohamed Khamla.

Fig. 1.2 Original. Based on Fig. 1.1 of Clarke (2014). Figure 1.2 is licensed under CC BY-SA 4.0 by Philippe Bertrand, Louis Legendre and Mohamed Khamla.

Fig. 1.3 This work, Fig. 1.3, is a derivative of https://commons.wikimedia.org/wiki/File:Oort_cloud_lrg.en.png by Nasa.gov, in the public domain. I, Mohamed Khamla, release this work in the public domain.

Fig. 1.4 This work, Fig. 1.4, is a derivative of https://commons.wikimedia.org/wiki/File:Solar_sys.jpg by Harman Smith and Laura Generosa (nee Berwin), NASA’s Jet Propulsion Laboratory, in the public domain. I, Mohamed Khamla, release this work in the public domain.

Fig. 1.5a This work, Fig. 1.5a, is a derivative of https://commons.wikimedia.org/wiki/File:Eccentricity.svg by Seahen https://commons.wikimedia.org/wiki/User:Seahen, used under GNU FDL CC BY-SA 3.0 and CC BY 2.5. Figure 1.5a is licensed under GNU FDL and CC BY-SA 3.0 by Mohamed Khamla.

Fig. 1.5b Original. Figure 1.5b is licensed under CC BY-SA 4.0 by Philippe Bertrand, Louis Legendre and Mohamed Khamla.

Fig. 1.6a https://commons.wikimedia.org/wiki/File:Earth_obliquity_range.svg by NASA, Mysid https://en.wikipedia.org/wiki/User:Mysid, in the public domain.

Fig. 1.6b https://commons.wikimedia.org/wiki/File:Earth_precession.svg by NASA, Mysid https://en.wikipedia.org/wiki/User:Mysid, in the public domain.

Fig. 1.7 The source of this material is the COMET^® Website at https://www.meted.ucar.edu/climate/climwaterpart1/media_gallery.php of the University Corporation for Atmospheric Research (UCAR), sponsored in part through cooperative agreement(s) with the National Oceanic and Atmospheric Administration (NOAA), U.S. Department of Commerce (DOC). ©1997–2017 University Corporation for Atmospheric Research. All Rights Reserved. Artist: Steven Deyo. With permission from COMET [In order to log into the MetEd website, one must create an account].

Fig. 1.8 This work, Fig. 1.8, is a derivative of https://commons.wikimedia.org/wiki/File:Inflation.PNG by Rogilbert, in the public domain. I, Mohamed Khamla, release this work in the public domain.

Fig. 1.9 This work, Fig. 1.9, is a derivative of http://www.astronomy.ohio-state.edu/~jaj/nucleo/ by Prof. Jennifer Johnson, used under CC BY-SA 4.0. The figure is explained in http://blog.sdss.org/2017/01/09/origin-of-the-elements-in-the-solar-system/ Figure 1.9 is licensed under CC BY-SA 4.0 by Mohamed Khamla.

Fig. 1.10a https://commons.wikimedia.org/wiki/File:Charniodiscus_arboreus.jpg by tina negus from UK https://www.flickr.com/people/84265607@N00, used under CC BY 2.0. Size added to the left of the photo.

Fig. 1.10b https://commons.wikimedia.org/wiki/File:DickinsoniaCostata.jpg by Verisimilus at English Wikipedia, used under GNU FDL, CC BY-SA 3.0 and CC BY 2.5. Size added to the left of the photo.

Fig. 1.10c https://commons.wikimedia.org/wiki/File:Opabinia_smithsonian.JPG by Jstuby at English Wikipedia https://en.wikipedia.org/wiki/User:Jstuby, in the public domain. Size added to the left of the photo.

Fig. 1.11 Original. Figure 1.11 is licensed under CC BY-SA 4.0 by Philippe Bertrand, Louis Legendre and Mohamed Khamla.