276
to be seen whether this perception is borne out in the long term. An optimist might
argue that the processes of asymmetry, axis formation, and self-organization have
fascinated scientists and have generated fundamental biological insight for well
over 100 years, and should continue to do so long into the future.
Acknowledgements The author would like to thank B. Fritzsch for assistance with German
translations. This work was supported by the University of Iowa.
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