Gigantic floating leaves occupy a large surface area at an economical material cost

Abstract

The giant Amazonian waterlily (genus Victoria ) produces the largest floating leaves in the plant kingdom. The leaves’ notable vasculature has inspired artists, engineers, and architects for centuries. Despite the aesthetic appeal and scale of this botanical enigma, little is known about the mechanics of these extraordinary leaves. For example, how do these leaves achieve gigantic proportions? We show that the geometric form of the leaf is structurally more efficient than those of other smaller species of waterlily. In particular, the spatially varying thickness and regular branching of the primary veins ensures the structural integrity necessary for extensive coverage of the water surface, enabling optimal light capture despite a relatively low leaf biomass. Leaf gigantism in waterlilies may have been driven by selection pressures favoring a large surface area at an economical material cost, for outcompeting other plants in fast-drying ephemeral pools.

Leaf unfolding and lamina biomechanics in Syngonium podophyllum and Pilea peperomioides

“…Euryale ferox, an aquatic plant bearing peltate leaves, unfolds its leaf halves simultaneously but, unlike P. peperomioides, the unfolding process is extremely fast, being completed in one day after initiation of unfolding [3]. The same unfolding pattern can be found in the giant waterlily Victoria amazonica [6].…”

“…The morphology and size of plant leaves is highly variable, ranging from tiny leaves in some cacti or conifers [1,2] to very large floating leaves that can support the weight of a small child [3]. Leaf shapes can vary from elliptic to oblong or compound, toothed and with or without lobation [4].…”

Revised Species Delimitation in the Giant Water Lily Genus Victoria (Nymphaeaceae) Confirms a New Species and Has Implications for Its Conservation

“…Victoria also has great potential to serve as a valuable model for exploring the biogeography of continental South America as it is an aquatic species mostly restricted to large river systems; its seeds are desiccation intolerant and thus unable to escape flooding plains of their water catchment. The ephemeral nature of such flooding plains ( Cowgill and Prance, 1989 ) is thought to have driven gigantism, as a mode of outcompeting other aquatic plants ( Box et al, 2022 ). Victoria could feasibly be part of a monophyletic clade comprising Microvictoria - Euryale - Victoria , as is suggested by morphological observations ( Gandolfo et al, 2004 ), the age of which predates the complete break up of Gondwana ca 83 Ma ( Seton et al, 2012 ).…”

“…Local names for V. amazonica that have been recorded include ‘ auapé-yaponna,’ after auapé ( Jacana jacana ), a small bird often seen running on its leaves ( Schultes, 1985 ; Box et al, 2022 ). Victoria cruziana has been called ‘ yrupé,’ ‘ yacare yrupé,’ or ‘ naanók lapotó ’ (‘ poncho del yacaré ’) ( Crovetto, 2012 ; Scarpa and Rosso, 2014 ; Mereles et al, 2020 ).…”

The Plant Leaf: A Biomimetic Resource for Multifunctional and Economic Design

“…For instance, the huge leaves of the giant Amazonian waterlilies from the plant genus Victoria require large material costs. Expending those costs may be reasonable for outcompeting other water plants, meaning that quickly and effectively covering the water surface pays dividends because it suppresses other water plants competing with Victoria for space [ 28 ]. There are more functional aspects of leaf shape relating to tree canopy architecture.…”