“…Moreover, the very species studied by Meyer‐Abich are currently used again as model organisms to investigate the development and evolution of holobionts and other host‐microbiotes collectives: lichens (Aschenbrenner, Cernava, Berg, & Grube, 2016; Cernava et al, 2019), sponges (Pita, Fraune, & Hentschel, 2016; Webster & Thomas, 2016) and various plants, ranging from mosses, like Marchantia spp., to orchid species (Alcaraz et al, 2018; Hassani, Durán, & Hacquard, 2018; Jacquemyn, Waud, Merckx, Lievens, & Brys, 2015; Vandenkoornhuyse, Quaiser, Duhamel, Van, & Dufresne, 2015). Remarkably, current views of holobionts, both in evo‐devo and microbiology, share with Meyer‐Abich the assumption of the phylogenetic ubiquitous nature and evolutionary centrality of holobiosis (Gilbert, 2019; Gilbert et al, 2012; McFall‐Ngai et al, 2013; Rosenberg & Zilber‐Rosenberg, 2018). For him, nature was a “universal mycorrhiza” (Meyer‐Abich, 1943).…”