Jeong-Min Kim

and 4 more

1. Many plants compensate for the damage caused by herbivorous insects through tolerance responses. Besides directly causing plant tissue loss and seed production reduction, herbivory causes phenological changes in the host plant. However, little is known about the fitness costs of phenological changes caused by tolerance responses to herbivorous attacks. 2. The girdling beetle Phytoecia rufiventris caused a short-term decrease in the number of flowers of the host plant Erigeron annuus. However, accelerated growth restored the number of flowers, but after a 2-week delay. With an objective to examine whether the tolerance response with such a delay fully compensates the fitness, we experimentally reproduced a 2-week delay in germination under greenhouse and field settings. Under both conditions, intraspecific competition resulted in serious defects in the growth and reproduction of E. annuus plants which of germination was delayed. However, delayed germination resulted in better growth when competition and herbivory were eliminated from the field. 3. Thus, we showed that the tolerance response to restore reproductive production does not fully compensate for the fitness loss caused by insect attack; rather, the delay in seed production in attacked plants leads to delayed germination and subsequent inferiority in intraspecific competition. 4. Synthesis. Our results imply that compensation for floral production after an herbivore attack does not fully restore offspring fitness in the presence of intraspecific competition and herbivory. Assessing the ecological consequences of defense traits in an appropriate layer of interaction is critical to interpreting adaptive values.

Song Hie Jung

and 1 more

The use of biota to analyze the spatial range and distribution of biogeographic regions is essential to gain a better understanding of the ecological processes that cause biotic differentiation and biodiversity at multiple spatiotemporal scales. Recently, the collection of high-resolution biological distribution data (e.g., specimens) and advances in analytical theory have led to their quantitative analysis and more refined spatial delineation. This study was conducted to redefine floristic zones in the southern part of the Korean Peninsula and to better understand the eco-evolutionary significance of the spatial distribution patterns. Based on the distribution data of 309,333 vascular plant species in the Korean Peninsula, we derived floristic zones using self-organizing maps. We compared the characteristics of the derived regions with those of historical floristic zones and ecologically important environmental factors (climate, geology, and geography). In a clustering analysis of the floristic assemblages, four distinct regions were identified, namely, the cold floristic zone (Zone I) in high-altitude regions at the center of the Korean Peninsula, cool floristic zone (Zone II) in high-altitude regions in the south of the Korean Peninsula, warm floristic zone (Zone III) in low-altitude regions in the central and southern parts of the Korean Peninsula, and maritime warm floristic zone (Zone IV) including the volcanic islands of Jejudo and Ulleungdo. A total of 1,099 taxa were common to the four floristic zones. Zone IV had the highest abundance of specific plants (those found in only one zone), with 404 taxa. This study improves floristic zone definitions using high-resolution regional biological distribution data. It will help better understand and re-establish regional species diversity. In addition, our study provides key data for hotspot analysis techniques required for the conservation of plant diversity.