Quote of the Week
(June 16, 2025)

Not only are the elements of an individual signaling pathway extremely flexible and adaptive; the individual pathway itself, once thought of as discrete and well-defined, doesn’t really exist — certainly not as a separate “mechanism.” Researchers now speak of the “multi-functionality” or “functional pleiotropism” of signaling nodes, pointing out that signaling networks have “ways of passing physiologically relevant stimulus information through shared channels” (Behar and Hoffmann 2010).

Whenever we imagine a biological process aimed at achieving some particular result, we need to keep in mind that every element in that process is likely playing a role in an indeterminate number of other significant, and seemingly goal-directed, activities. The mystery in all this does not lie primarily in isolated “mechanisms” of interaction. The question, rather, is why things don’t fall completely apart.

In sum: messages do not fly back and forth as metaphors or disembodied abstractions. They move as dynamically sculpted currents of force and energy. Their meanings are mimed or gestured — neither translated into, nor reduced to, a kind of expressionless Morse code, nor impelled along precisely incised channels like computer instructions. And what holds them together amid the ceaseless flows and crosstalk and molecular transformation is the unity of meaning that is the whole organism.

(from Chapter 9, “A Mess of Causes”, in Organisms and Their Evolution — Agency and Meaning in the Drama of Life)

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