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California Lake's Arsenic Hints At a Shadow Biosphere
MichaelSmith writes "Scientists think that there might be arsenic-based life in Mono Lake, California. If it's shown to exist, such life could have evolved independently from our own, or it could have forked from ours at a very early stage."
I had just read about this possibility today in this book, a fascinating compendium of mini-essays by leading thinkers about scientific or social developments that may be around the corner. Existing tests for biological organisms are geared towards a working asssumption that life forms will be part of the basic, familiar biological tree that we are based on. A "shadow biosphere" was discussed as something that could potentially be an alternative hierarchy of life, so unfamiliar that we haven't understood how to look for it even though it could be relatively populous in certain niche areas of the earth.
Finding an alternative pathway to the evolution of complex life forms could affect our perception of how common life is in the universe and could be a stunning treasure trove of discovery and insight for biologists.
Probably. Arsenic is toxic to us because of its chemical similarity to phosphorous. It reacts enough like phosphorous to get pulled into various reactions in our cells, and then enough differently to make the processes fail. In an organism that used arsenic instead of phosphorous, phosphorous would cause the same trouble.
Computer analogy -- In the old Eastern Bloc, clones of Western chips were reportedly made using "metric inches" of 25 millimeters instead of American inches of 25.4 mm. This worked fine electrically and mechanically when all the gear you were using was made to the same spec, but if you unknowingly tried to put a Western-made chip on 1/10th inch spacing into an Eastern Bloc socket on 2.5 mm spacing, or vice-versa, the incompatibility could cause failures. Similarly, it might be possible to build a cellular chemistry using arsenic instead of phosphorous. But if you put arsenic into a creature built with phosphorous or vice-versa, you're likely going to have failures as the cell unknowingly plugs the wrong element in.