Been reading your article of the above title and wanted to express something on the following:
"Proposed robotic micro-scavengers and cleaning units, while feasible, will be expensive, difficult to maintain, and likely to be far less efficient at many tasks than their natural counterparts--but also more predictable. Until they become practical, however, the issue is moot."
It seems science in general is very concerned with artificial resolutions to many issues, in this case biological....whereas our bodies are naturally very capable...and there is evidence, of varying types and degress, that supports the notion each of us is latently capable of directly interacting with our bodies to ensure health - let alone balance within our environment.
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