Developmental constraints and resource environment shape early emergence and investment in spines in saplings.

摘要: BACKGROUND AND AIMS Herbivory by large mammals imposes a critical recruitment bottleneck on plants in many systems. Spines defend against herbivores, and how early they emerge saplings may be one of the strongest predictors sapling survival herbivore-rich environments. Yet little effort has been directed at understanding variability spine emergence across saplings. METHODS We present multispecies study examining whether size, type species' environmental niche (light precipitation environment) influence biomass investment spines. A phylogenetically diverse pool 45 species possessing different types (spines, prickles thorns; that are derived from distinct plant organs: leaf, epidermis or cortex, branch, respectively), were grown under common-garden conditions, patterns allocation to spines 5 15 weeks after transplanting characterized. KEY RESULTS Spine resource main factors driving patterns. emerged earliest leaf spine-bearing species, latest thorn-bearing species. The probability increased with decreasing precipitation, was greater open than closed habitats. Sapling changed mass but contingent habitat type. CONCLUSIONS Different have strikingly timing expression, suggesting developmental origins play role defences. Furthermore, light environments (open vs. habitats) showed contrasting limitation their native range driven divergent evolution defence expression.