Quote of the Week
(October 13, 2025)

From the eminent twentieth-century student of animal form, Adolf Portmann, writing about the colorful pattern on a duck’s wing:

“If ... we look at the speculum on a duck’s wing, we might imagine that an artist had drawn his brush across some ten blank feathers, which overlap sideways — making white, bluey-green, and black lines — so that the stroke of the brush touched only the exposed part of each feather. The pattern is a single whole, superimposed on the individual feathers, so that the design on each, seen by itself, no longer appears symmetrical. We realize the astonishing nature of such a combined pattern only when we consider that it develops inside several or many feather sheaths completely separated from one another; and that in each individual feather it appears at an early stage while it is still tightly rolled up, the joint pattern not being produced until these feathers are unfolded. What sort of unknown forces direct the constructional work in the ‘painting’ of these feather germs?”

(from Chapter 11, “Why We Cannot Explain the Form of Organisms”, in Organisms and Their Evolution — Agency and Meaning in the Drama of Life)

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