Microbes In The News-Early Life
Earliest life may have arisen in ponds, not oceans
Date: April 12, 2019
Source: Massachusetts Institute Of Technology
News Coverage: Jenifer Chu, ScienceDaily
Micro Post: Lukash Platil
MIT researchers report shallow bodies of water rich in nitrogen may have been the source of initial life on earth. These ponds, shallower then 10 cm are thought to have contained large amounts of nitrogenous oxides. Stating that oceans may have been a bad place for necessary nitrogen reactions to occur and jump start life. This idea is based on free floating RNA being present and chemically interacting with various nitrogenous oxides. Atmospheric nitrogen was most likely broken into oxide forms by frequent lightning storms and accumulated in water but nitrogenous oxide sinks on oceans would likely break down too much of the substance. Shallow ponds would have allowed for synthesis pathways to occur at a higher concentration but at a lower scale due to the low abundance of ponds on early earth.
We discussed many possibility for the origin of life on earth in class. Many origins focused on the possibility of interactions between ocean water and hydro thermal vents to create a Goldie Locks zone in which life could have spawned. We discussed what is believed to be chemically necessary for early life on earth to span. The conversion of atmospheric N2 to oxide forms and its relative abundance is what these researchers believe is the deciding factor.
I think pointing out how stable N2’s triple bond is a key factor in allowing synthesis pathways to occur. The new nitrogen sinks researchers thought of that would decrease the relative abundance of the reactive species by three orders of magnitude in oceans seems like a reasonable justification to reevaluate the location for the emergence of life. The researchers belong to MIT, the paper was published in a credible journal and the news coverage was done by a reputable, scientific news outlet.
Do you think the statistical chance of life emergence depends on the quality of environment for synthesis pathways to occur or the relative abundance of locations containing the necessary ingredients for life? i.e. Quality or quantity, which is more important?