1. Emergence of Life in a Radically Different Environment

    An icy lake in Svalbard, Norway, taken by an unmanned aerial vehicle. Life on Earth may have begun in an environment with both water and ice, and modern analogs may help the scientific community understand how. Image credit: Marjorie D. Cantine. (via Astrobiology Magazine) Image credit: None
    An icy lake in Svalbard, Norway, taken by an unmanned aerial vehicle. Life on Earth may have begun in an environment with both water and ice, and modern analogs may help the scientific community understand how. Image credit: Marjorie D. Cantine. (via Astrobiology Magazine)

    Marjorie Cantine, graduate student with the Earth, Atmospheric and Planetary Sciences department at MIT, and Greg Fournier, professor of Geobiology at MIT and a member of the Foundations of Complex Life team of the NASA Astrobiology Institute, have co-authored a paper tracing possible evidence for the beginnings of life under very different environmental conditions currently assumed for the last universal common ancestor (LUCA). Cantine and Fournier suggest how that separate evolution might shift our thinking about LUCA and provide a different take on how we assume life emerged within extreme environments such as Mars.

    Excerpted from the feature story by Charles Q. Choi at Astrobiology Magazine:

    Life on Earth could have originated in cold conditions near the surface, before spreading to warmer environments, according to research that analyzes the possible gene sequences belonging to the earliest life.

    All life on Earth today originates from two distinct developments in our planet’s biological history. These are the emergence of the first life forms billions of years ago, and the subsequent evolution of the last universal common ancestor (LUCA) of all extant organisms.

    Whatever they were at the time, these two extinct species – the first life and LUCA – likely occupied radically different environments, suggesting that early life had to undergo a series of evolutionary changes of which traces may still be detectable in organisms alive today.

    Read more at Astrobiology Magazine.

    “Environmental Adaptation from the Origin of Life to the Last Universal Common Ancestor” is published in Origins of Life and Evolution of Biospheres.

    Source: [Astrobiology Magazine]