The Archaeal Concept and the World it Lives in: A Retrospective.

The present retrospective concerns the discovery and development of the archaea, the so-called 'third form of life' that no one anticipated and many did not, and still do not want. In its birth pangs, which the archaea had a plenty, the concept encountered biology unmasked; for it ran up against some of the key struts in the 20th century biological edifice. Consequently, the history of the development of the archaeal concept provides an excellent window on certain of the weaknesses in the 20th century biology paradigm, weaknesses that have now led that paradigm to a conceptual dead end. On the other hand, the archaeal concept has also provided us one of the pillars on which a new holistic paradigm for biology can be built. So, it would seem of value to retrace some of the twists and turns in the history of the development of the archaeal concept. Given my position vis-à-vis the archaea, my account will be a personal one.