The global trend in plant twining direction

Abstract

AimTo examine, at a global scale, patterns in the direction in which climbing plants twine. We tested three hypotheses: (1) that twining direction is determined randomly; (2) that twining direction is determined by apices following the apparent movement of the sun across the sky; and (3) that twining direction is determined by the Coriolis effect.Location Seventeen sites spanning nine countries, both hemispheres and 65 ° of latitude.Methods Twining direction was recorded for the first c . 100 stems encountered along transects through natural vegetation at each site.Results Ninety-two per cent of the 1485 twining stems we recorded grew in righthanded helices, i.e. they twined in an anticlockwise direction. This is significantly ( P < 0.001) different from random. The proportion of stems twining right-handedly (anticlockwise) was independent of both latitude ( P = 0.33) and hemisphere ( P = 0.63). These data are inconsistent with the idea that twining direction is determined by either the relative passage of the sun through the celestial sphere or by the Coriolis effect. Thus, we reject all three of our hypotheses. Main conclusionsThe predominance of right-handed helical growth in climbing plants cannot be explained by hypotheses attempting to link plant growth behaviour and global location. One alternative hypothesis for our findings is that the widespread phenomenon of anticlockwise twining arises as a function of microtubule orientation operating at a subcellular level.

Cellular and Nuclear Alignment Analysis for Determining Epithelial Cell Chirality

“…Left-right (LR) asymmetry, or chirality, is a well conserved phenomenon in the nature, from dextral and sinistral helices in the shells of snails 17 , LR asymmetry of the internal organs and the central nervous system of mammals 11, 14 , to the significant right handed bias in the rotation of climbing plants during twining 6 . Deviations of normal asymmetry often lead to birth defects such as situs ambiguous , where one or two the internal organs are in mirrored position 31 .…”

Micropatterned mammalian cells exhibit phenotype-specific left-right asymmetry

“…cell patterning | tissue morphogenesis | cell polarity | cell migration L eft-right (LR) asymmetry is seen in the development of numerous living organisms, including climbing plants (1), helices of snail shells (2), and the human body (3,4). Genetic diseases and prenatal exposure to teratogens can cause birth defects in laterality (5,6).…”

The effect of different chiral morphs on visitation rates and fruit set in the orchid Spiranthes spiralis

“…More rarely, chirality has been reported also for flower morphs and inflorescences (Davis 1964;Davis and Ramanujacharyulu 1971;Kihara 1972;Jesson and Barrett 2000;Fenster 2014, 2016). Although the vast majority of plants are fixed for one coiling direction (Edwards et al 2007), the cause for this directionality is known in only a few cases (Vermeij 1975;Barrett 2000, 2002). In particular, Hashimoto (2002) and Ishida et al (2007) discovered that SPIRAL1-like genes are involved in twisted growth of various plant species.…”