Acorn size and tolerance to seed predators:the multiple roles of acorns as food for seed predators,fruit for dispersal and fuel for growth

作     者：Andrew W.BARTLOW Salvatore JAGOSTA Rachel CURTIS Xianfeng YI Michael ASTEELE 

作者机构：Department of Biology and The WIESS Institute for Environmental Science and SustainabilityWilkes UniversityWilkes BarrePennsylvaniaUSA Present address:Department of BiologyUniversity of UtahSalt Lake CityUtahUSA Center for Environmental Studies and Department of BiologyVirginia Commonwealth UniversityRichmondVirginiaUSA Present address:Department of Veterinary Integrative BiosciencesTexas A&M UniversityCollege StationTexasUSA College of Life SciencesJiangxi Normal UniversityNanchangJiangxiChina. 

出 版 物：《Integrative Zoology》 (整合动物学（英文版）)

年 卷 期：2018年第13卷第3期

页      面：251-266页

核心收录：

学科分类：0710[理学-生物学] 071001[理学-植物学] 07[理学] 0905[农学-畜牧学] 0906[农学-兽医学] 

基　　金：This study was supported by funding from the Howard Hughes Medical Institute to M.A.S. the Natural Science Foundation of China(No.31172101)to X.F.Y. the National Basic Research Program of China(No.2007CB109100)to X.F.Y. the H.Fenner Research Fund of Wilkes University(M.A.S.) M.A.S also recognizes support of a Bullard Fellowship from Harvard Forest,Harvard University and the National Science Foundation(DEB 15556707) Support during final preparation of the manuscript was provided by the National Science Foundation Graduate Research Fellowship Program to A.W.B.and R.C. 

主　　题：acorns damage tolerance dispersal Quercus seed size 

摘      要：Fitness of parents and offspring is affected by offspring size.In oaks(Quercus spp.),acorns vary considerably in size across,and within,species.Seed size influences dispersal and establishment of oaks,but it is not known whether size imparts tolerance to seed predators.Here,we examine the relative extent to which cotyledon size serves as both a means for sustaining partial consumption and energy reserves for developing seedlings during early stages of establishment.Acorns of 6 oak species were damaged to simulate acorn predation by vertebrate and invertebrate seed predators.Seedling germination/emergence and growth rates were used to assess seedling performance.We predicted that if cotyledons are important for dispersal,acorns should show tolerance to partial seed consumption.Alternatively,if the cotyledon functions primarily as an energy reserve,damage should significantly influence seedling performance.Acorns of each species germinated and produced seedlings even after removing50%of the cotyledon.Seed mass explained only some of the variation in performance.Within species,larger acorns performed better than smaller acorns when damaged.Undamaged acorns performed as well or better than damaged acorns.There was no pattern among individual species with increasing amounts of damage.In some species,simulated invertebrate damage resulted in the poorest performance,suggesting alternative strategies of oaks to sustain damage.Large cotyledons in acorns may be important for attracting seed dispersers and sustaining partial damage,while also providing energy to young seedlings.Success of oak establishment may follow from the resilience of acorns to sustain damage at an early stage.