Who Needs Iron?

Abstract

Everything alive needs iron, not too much of it and not too little. In the biosphere, where this toxic, essential element is pervasive, life has adapted itself to maintain a precarious balance. Organisms have means to exclude the iron not needed, to husband the iron required and to neutralize the toxicity of iron that is present but, for the moment, not usefully employed.Most forms of life are unable to absorb or utilize most of the iron in the earth's crust. In the perspective of evolution this must be regarded as a protective mechanism — this failure to develop biologic . . .