Swarms, swarming and entanglements of fungal hyphae and of plant roots

Abstract

There has been recent interest in the possibility that plant roots can show oriented collective motion, or swarming behavior. We examine the evidence supportive of root swarming and we also present new observations on this topic. Seven criteria are proposed for the definition of a swarm, whose application can help identify putative swarming behavior in plants. Examples where these criteria are fulfilled, at many levels of organization, are presented in relation to plant roots and root systems, as well as to the root-like mycelial cords (rhizomorphs) of fungi. The ideas of both an “active” swarming, directed by a signal which imposes a common vector on swarm element aggregation, and a “passive” swarming, where aggregation results from external constraint, are introduced. Active swarming is a pattern of cooperative behavior peculiar to the sporophyte generation of vascular plants and is the antithesis of the competitive behavior shown by the gametophyte generation of such plants, where passive swarming may be found. Fungal mycelial cords could serve as a model example of swarming in a multi-cellular, non-animal system.

The botanical multiverse of Peter Barlow

“…Roots grow through the soil away from the host plant and are likely to interact with other roots, in the substrate. A typically idiosyncratic take on this was Peter's work looking at plant roots and fungal hyphae [84]. However, rather than examine the more obvious fungus/higher plant connection of mycorrhizaan ancient mutualism [85,86] of importance both to land plant's evolutionary success and to continued and continuing productivity of the host plant [87] they compared the 'oriented collective motion'of plant roots to the 'swarming'of fungal hyphae.…”

The natural history of consciousness, and the question of whether plants are conscious, in relation to the Hameroff-Penrose quantum-physical ‘Orch OR’ theory of universal consciousness

“…The gathering together of parts that were once separate is similar to what occurs in swarming or flocking events among insects and birds. 168 It is as though, by means of an internal act of primary perception, the plant or tree has a sense (or consciousness overseen by a Mind at state 3), not only of its parts, but also of its form; and through this self-awareness of form arises the means whereby a plant's own oneness can be attained. An aspect of this tendency towards oneness derives from the property of whole-plant 'correlation'.…”

Analysis of Root System Architecture Affected by Swarming Behavior

“…The root system architecture (RSA) is a very important component of a plant's strategy to survive, representing the adaptation to the available nutrients in the soil (McCleery et al 2017). Root systems have developed complex architectures to optimally exploit soil nutrients (Barlow & Fisahn 2013). In the process of the interaction between a root system and soil, the root system can acclimate to the environment through architectural changes that act at the root-type level changes (Rellán-Álvarez et al 2016).…”

“…Matos et al (2014) used the collective decision of apexes to decide which nutrients to explore. Barlow and Fisahn (2013) described a set of swarming criteria that is generally acceptable for plants and animals. Then, evidence was presented to show that swarming might be a property of roots.…”