Mohammed Armani1,2, Tristan Charles-Dominique3, Kasey E Barton4, Kyle W Tomlinson1. 1. Center for Integrative Conservation, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan, China. 2. University of Chinese Academy of Science, No. 19A Yuquan Road, Beijing, China. 3. CNRS UMR7618; Sorbonne University, Institute of Ecology and Environmental Sciences Paris, Paris, France. 4. Department of Botany, University of Hawaii at Manoa, 3190 Maile Way, Room 101, Honolulu, HI, USA.
Abstract
BACKGROUND AND AIMS: Herbivory by large mammals imposes a critical recruitment bottleneck on plants in many systems. Spines defend plants against large herbivores, and how early they emerge in saplings may be one of the strongest predictors of sapling survival in herbivore-rich environments. Yet little effort has been directed at understanding the variability in spine emergence across saplings. METHODS: We present a multispecies study examining whether and how sapling size, spine type and species' environmental niche (light and precipitation environment) influence early emergence and biomass investment in spines. A phylogenetically diverse pool of 45 species possessing different spine types (spines, prickles and thorns; that are derived from distinct plant organs: leaf, epidermis or cortex, and branch, respectively), were grown under common-garden conditions, and patterns of spine emergence and biomass allocation to spines at 5 and 15 weeks after transplanting were characterized. KEY RESULTS: Spine type and species' resource niche were the main factors driving early emergence and investment patterns. Spines emerged earliest in leaf spine-bearing species, and latest in thorn-bearing species. The probability of early spine emergence increased with decreasing precipitation, and was greater in species from open than from closed habitats. Sapling investment in spines changed with plant mass but was contingent on spine type and habitat type. CONCLUSIONS: Different spine types have strikingly different timing of expression, suggesting that developmental origins of spines play a critical role in sapling defences. Furthermore, species from different precipitation and light environments (open vs. closed habitats) showed contrasting patterns of early spine expression, suggesting that resource limitation in their native range may have driven divergent evolution of early defence expression.
BACKGROUND AND AIMS: Herbivory by large mammals imposes a critical recruitment bottleneck on plants in many systems. Spines defend plants against large herbivores, and how early they emerge in saplings may be one of the strongest predictors of sapling survival in herbivore-rich environments. Yet little effort has been directed at understanding the variability in spine emergence across saplings. METHODS: We present a multispecies study examining whether and how sapling size, spine type and species' environmental niche (light and precipitation environment) influence early emergence and biomass investment in spines. A phylogenetically diverse pool of 45 species possessing different spine types (spines, prickles and thorns; that are derived from distinct plant organs: leaf, epidermis or cortex, and branch, respectively), were grown under common-garden conditions, and patterns of spine emergence and biomass allocation to spines at 5 and 15 weeks after transplanting were characterized. KEY RESULTS: Spine type and species' resource niche were the main factors driving early emergence and investment patterns. Spines emerged earliest in leaf spine-bearing species, and latest in thorn-bearing species. The probability of early spine emergence increased with decreasing precipitation, and was greater in species from open than from closed habitats. Sapling investment in spines changed with plant mass but was contingent on spine type and habitat type. CONCLUSIONS: Different spine types have strikingly different timing of expression, suggesting that developmental origins of spines play a critical role in sapling defences. Furthermore, species from different precipitation and light environments (open vs. closed habitats) showed contrasting patterns of early spine expression, suggesting that resource limitation in their native range may have driven divergent evolution of early defence expression.
Authors: Angela T Moles; Begoña Peco; Ian R Wallis; William J Foley; Alistair G B Poore; Eric W Seabloom; Peter A Vesk; Alejandro J Bisigato; Lucrecia Cella-Pizarro; Connie J Clark; Philippe S Cohen; William K Cornwell; Will Edwards; Rasmus Ejrnaes; Therany Gonzales-Ojeda; Bente J Graae; Gregory Hay; Fainess C Lumbwe; Benjamín Magaña-Rodríguez; Ben D Moore; Pablo L Peri; John R Poulsen; James C Stegen; Ruan Veldtman; Hugo von Zeipel; Nigel R Andrew; Sarah L Boulter; Elizabeth T Borer; Johannes H C Cornelissen; Alejandro G Farji-Brener; Jane L DeGabriel; Enrique Jurado; Line A Kyhn; Bill Low; Christa P H Mulder; Kathryn Reardon-Smith; Jorge Rodríguez-Velázquez; An De Fortier; Zheng Zheng; Pedro G Blendinger; Brian J Enquist; Jose M Facelli; Tiffany Knight; Jonathan D Majer; Miguel Martínez-Ramos; Peter McQuillan; Francis K C Hui Journal: New Phytol Date: 2013-01-14 Impact factor: 10.151