Fig. 27.1 The dual hypothesis applied to the structure and organization of lichens, using Usnea as a
case study. Simon Schwendener’s photo credits: Meise Botanic Garden, Belgium and Europeana.
Lichen photos from the author
Fig. 27.2 Anton de Bary and the introduction of the symbiosis concept in 1878 (De Bary 1878).
Heinrich Anton de Bary’s photo credits: https://www.archi-wiki.org/Personne:Anton_de_Bary#/
media/File:39176.jpg
27 The Importance of Being Symbiont and the Role of Symbiosis as a Driving Force. . .
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