• The Countdown: 6/1/2011

    Lots of must-read stuff in today’s issue of Nature Geoscience, including a correspondence on “Biogenicity of Apex Chert microfossils.

    3… There’s also a letter on the origins of Titan’s atmosphere, in which the authors claim the source of N2 in the impacts. They make these claims based on impact simulations that show NH4 could have been converted to N2.

    2… Another Nature Geosciences letter, this one on potential false positives in the search for the earliest life on Earth. This work relates to apatite-associated graphite with low carbon isotope ratios. These pieces of evidence have been used before in the search for the most ancient record of life on Earth. The problem is… in this case, the material is non-biogenic, and formed around a billion years after the host rock.

    1… One more letter, this one open-access, on the potential role of microbial mats in the evolution of mobile animals. This is just fascinating stuff. The paper argues that microbial mats provided both a food and oxygen source to the first mobile animals – animals that would have developed on a relatively low-O2 planet. Because animals combine O2 and food for energy to do things (like move), this makes for a very self-consistent story.

    Launch… and land!!