Biodiversity Science ›› 2017, Vol. 25 ›› Issue (6): 683-688.doi: 10.17520/biods.2017122

• Forum • Previous Article    

Natural hybridization and biodiversity conservation

Hui Shang, Yuehong Yan*()   

  1. Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences; Shanghai Chenshan Botanical Garden, Shanghai 201602
  • Received:2017-04-16 Accepted:2017-06-10 Online:2017-07-10
  • Yan Yuehong

Hybridization occurs commonly in nature. Due to decreasing fitness, a large number of hybridized offspring might be eliminated in natural conditions, but many hybridization/introgression events can be important drivers of speciation. With advances in modern molecular genotyping methods, the mechanisms of hybridization and their impacts on speciation are becoming better understood. However, for taxa with hybridized origins, the question of whether the germplasm needs to be conserved presents many viewpoints. Here, we comprehensively review the conservation value of hybrids over three aspects (including genetic diversity, species diversity, and ecosystem diversity) to pronounce the significant roles in evolution and ecology. A large number of cases indicate that not all hybridization will lead to genetic assimilation by hybridization swamping. It can also boost genetic diversity and increase fitness and adaptability. Based on recent research on natural hybridization, we propose a principle for conservation of hybridized originated taxa if the existing hybridized taxon does not threaten the parental species, and its unique germplasm can contribute to genetic and adaptive capacity. In such a situation, the conservation of hybridized taxa should be taken into consideration. We hope this proposal could supplement a reference to reinforce conservation policy and species red listing.

Key words: natural hybridization, biodiversity, conservation biology, species red list

Fig. 1

Principle for the conservation of natural hybridization"

[1] Abbott R, Albach D, Ansell S, Arntzen JW, Baird SJ, Bierne N, Boughman J, Brelsford A, Buerkle CA, Buggs R (2013) Hybridization and speciation. Journal of Evolutionary Biology, 26, 229-246.
[2] Allendorf FW, Leary RF, Spruell P, Wenburg JK (2001) The problems with hybrids: setting conservation guidelines. Trends in Ecology & Evolution, 16, 613-622.
[3] Anderson E, Stebbins G Jr (1954) Hybridization as an evolutionary stimulus. Evolution, 378-388.
[4] Arnold ML (1992) Natural hybridization as an evolutionary process. Annual Review of Ecology and Systematics, 23, 237-261.
[5] Bohling JH (2016) Strategies to address the conservation threats posed by hybridization and genetic introgression. Biological Conservation, 203, 321-327.
[6] Coyne JA, Orr HA (2004) Speciation. Sinauer Associates Inc., Sunderland, MA.
[7] Ebihara A, Nakato N, Amoroso VB, Hidayat A, Kuo LY (2016) Monachosorum arakii Tagawa (Dennstaedtiaceae) is a relict “international” hybrid: a reassessment of the Monachosorum species. Systematic Botany, 41, 586-595.
[8] Fitzpatrick BM, Shaffer HB (2007) Hybrid vigor between native and introduced salamanders raises new challenges for conservation. Proceedings of the National Academy of Sciences, USA, 104, 15793-15798.
[9] Gow JL, Peichel CL, Taylor EB (2006) Contrasting hybridization rates between sympatric three-spined sticklebacks highlight the fragility of reproductive barriers between evolutionarily young species. Molecular Ecology, 15, 739-752.
[10] Grant PR, Grant BR (2014) Evolutionary biology: speciation undone. Nature, 507, 178-179.
[11] Gross B, Rieseberg L (2005) The ecological genetics of homoploid hybrid speciation. Journal of Heredity, 96, 241-252.
[12] Hayashi M, Kato J, Ohashi H, Mii M (2009) Unreduced 3x gamete formation of allotriploid hybrid derived from the cross of Primula denticulata (4x) × P. rosea (2x) as a causal factor for producing pentaploid hybrids in the backcross with pollen of tetraploid P. denticulata. Euphytica, 169, 123.
[13] Hill KD (1993) The endangered species act: what do we mean by species. Boston College Environmental Affairs Law Review, 20, 239.
[14] Hori K, Tono A, Fujimoto K, Kato J, Ebihara A, Watano Y, Murakami N (2014) Reticulate evolution in the apogamous Dryopteris varia complex (Dryopteridaceae, subg. Erythrovariae, sect. Variae) and its related sexual species in Japan. Journal of Plant Research, 127, 661-684.
[15] IUCN (2013) The IUCN Red List of Threatened Species. IUCN, Gland, Switzerland.
[16] IUCN (2014) Guidelines for Using the IUCN Red List Categories and Criteria, Version 11. IUCN, Gland, Switzerland.
[17] Jackiw RN, Mandil G, Hager HA (2015) A framework to guide the conservation of species hybrids based on ethical and ecological considerations. Conservation Biology, 29, 1040-1051.
[18] Kasari L, Saar L, de Bello F, Takkis K, Helm A (2016) Hybrid ecosystems can contribute to local biodiversity conservation. Biodiversity and Conservation, 25, 3023-3041.
[19] Kleindorfer S, O’Connor JA, Dudaniec RY, Myers SA, Robertson J, Sulloway FJ (2014) Species collapse via hybridization in Darwin’s tree finches. The American Naturalist, 183, 325-341.
[20] Mallet J (2007) Hybrid speciation. Nature, 446, 279.
[21] May R (1976) Theoretical Ecology. Saunders, Philadelphia.
[22] Nolte AW, Tautz D (2010) Understanding the onset of hybrid speciation. Trends in Genetics, 26, 54-58.
[23] Piett S, Hager HA, Gerrard C (2015) Characteristics for evaluating the conservation value of species hybrids. Biodiversity and Conservation, 24, 1931-1955.
[24] Richards ZT, Hobbs JPA (2015) Hybridisation on coral reefs and the conservation of evolutionary novelty. Current Zoology, 61, 132-145.
[25] Rieseberg LH (1991) Homoploid reticulate evolution in Helianthus (Asteraceae): evidence from ribosomal genes. American Journal of Botany, 1218-1237.
[26] Rolán-Alvarez E (2007) Sympatric speciation as a by-product of ecological adaptation in the Galician Littorina saxatilis hybrid zone. Journal of Molluscan Studies, 73, 1-10.
[27] Rothfels CJ, Johnson AK, Hovenkamp PH, Swofford DL, Roskam HC, Fraser-Jenkins CR, Windham MD, Pryer KM (2015) Natural hybridization between genera that diverged from each other approximately 60 million years ago. The American Naturalist, 185, 433-442.
[28] Seehausen O (2004) Hybridization and adaptive radiation. Trends in Ecology & Evolution, 19, 198-207.
[29] Seehausen O (2006) Conservation: losing biodiversity by reverse speciation. Current Biology, 16, R334-R337.
[30] Shang H, Wang Y, Zhu XF, Zhao GH, Wang FH, Lu JM, Yan YH (2016) Likely allopatric origins of Adiantum× meishanianum (Pteridaceae) through multiple hybridizations. Journal of Systematics and Evolution, 54, 528-534.
[31] Soltis DE, Visger CJ, Soltis PS (2014) The polyploidy revolution then and now: Stebbins revisited. American Journal of Botany, 101, 1057-1078.
[32] Stelkens RB, Brockhurst MA, Hurst GD, Greig D (2014) Hybridization facilitates evolutionary rescue. Evolutionary Applications, 7, 1209-1217.
[33] Taylor E, Boughman J, Groenenboom M, Sniatynski M, Schluter D, Gow J (2006) Speciation in reverse: morphological and genetic evidence of the collapse of a three- spined stickleback (Gasterosteus aculeatus) species pair. Molecular Ecology, 15, 343-355.
[34] Tsutsumi C, Hirayama Y, Kato M, Yatabe-Kakugawa Y, Zhang S (2012) Molecular evidence on the origin of Osmunda × mildei (Osmundaceae). American Fern Journal, 102, 55-68.
[35] Vilà M, Weber E, Antonio CM (2000) Conservation implications of invasion by plant hybridization. Biological Invasions, 2, 207-217.
[36] Wang XR, Szmidt AE, Savolainen O (2001) Genetic composition and diploid hybrid speciation of a high mountain pine, Pinus densata, native to the Tibetan Plateau. Genetics, 159, 337-346.
[37] Wang Y, Shang H, Gu YF, Wei HJ, Zhao GH, Dai XL, Yan YH (2015a) A new cryptic hybrid species of Adiantum L. (Pteridaceae) identified by nuclear and chloroplast DNA sequences. Chinese Science Bulletin, 60, 922-932.
[38] Wang Y, Shang H, Zhou XL, Zhao GH, Dai XL, Yan YH (2015b) Adiantum× ailaoshanense (Pteridaceae), a new natural hybrid from Yunnan, China. Phytotaxa, 236, 266-272.
[39] Whitham TG, Martinsen GD, Keim P, Floate KD, Dungey HS, Potts BM (1999) Plant hybrid zones affect biodiversity: tools for a genetic-based understanding of community structure. Ecology, 80, 416-428.
[40] Wu W (2009) Natural Hybridization, Phylogeography and Speciation Patterns of Altingiaceae. PhD dissertaion, Sun Yat-sen University, Guangzhou.(in Chinese with English abstract)
[吴伟 (2009) 阿丁枫科的自然杂交、亲缘地理学与物种形成模式. 中山大学博士学位论文, 广州.]
[41] Wu W, Zhou R, Huang Y, Boufford DE, Shi S (2010) Molecular evidence for natural intergeneric hybridization between Liquidambar and Altingia. Journal of Plant Research, 123, 231-239.
[42] Wyk AM, Dalton DL, Hoban S, Bruford MW, Russo IRM, Birss C, Grobler P, Vuuren BJ, Kotzé A (2017) Quantitative evaluation of hybridization and the impact on biodiversity conservation. Ecology and Evolution, 7, 320-330.
[43] Yakimowski SB, Rieseberg LH (2014) The role of homoploid hybridization in evolution: a century of studies synthesizing genetics and ecology. American Journal of Botany, 101, 1247-1258.
[44] Zhang JL (2007) Natural Hybridization Origin of Rhododendron agastum (Ericaceae) in Yunnan, China. PhD dissertaion, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming. (in Chinese with English abstract)
[张敬丽 (2007) 杜鹃花属迷人杜鹃的自然杂交起源研究. 中国科学院昆明植物研究所博士学位论文, 昆明.]
[45] Zhou QJ, Cai YC, Ng WL, Wu W, Dai SP, Wang F, Zhou RC (2017) Molecular evidence for natural hybridization between two Melastoma species endemic to Hainan and their widespread congeners. Biodiversity Science, 25, 638-646. (in Chinese with English abstract)
[周秋杰, 蔡亚城, 黄伟伦, 吴伟, 代色平, 王峰, 周仁超 (2017) 野牡丹属两个海南特有种与同属广布种自然杂交的分子证据. 生物多样性, 25, 638-646.]
[1] Xing Yuan, Wu Xiaoping, Ouyang Shan, Zhang Junqian, Xu Jing, Yin Senlu, Xie Zhicai. Assessment of macrobenthos biodiversity and potential human-induced stressors in the Ganjiang River system [J]. Biodiv Sci, 2019, 27(6): 648-657.
[2] Zou Anlong, Ma Suhui, Ni Xiaofeng, Cai Qiong, Li Xiuping, Ji Chengjun. Response of understory plant diversity to nitrogen deposition in Quercus wutaishanica forests of Mt. Dongling, Beijing [J]. Biodiv Sci, 2019, 27(6): 607-618.
[3] Liu Yan, Yang Yushuang. Importance of conservation priority areas for bryophyte biodiversity in Chongqing [J]. Biodiv Sci, 2019, 27(6): 677-682.
[4] Gui Xujun, Lian Juyu, Zhang Ruyun, Li Yanpeng, Shen Hao, Ni Yunlong, Ye Wanhui. Vertical structure and its biodiversity in a subtropical evergreen broad- leaved forest at Dinghushan in Guangdong Province, China [J]. Biodiv Sci, 2019, 27(6): 619-629.
[5] Mu Jun, Wang Jiaojiao, Zhang Lei, Li Yunbo, Li Zhumei, Su Haijun. Field monitoring using infrared cameras and activity rhythm analysis on mammals and birds in Xishui National Nature Reserve, Guizhou, China [J]. Biodiv Sci, 2019, 27(6): 683-688.
[6] Zhang Xiaoling, Li Yichao, Wang Yunyun, Cai Hongyu, Zeng Hui, Wang Zhiheng. Influence of future climate change in suitable habitats of tea in different countries [J]. Biodiv Sci, 2019, 27(6): 595-606.
[7] Li Hanxi, Huang Xuena, Li Shiguo, Zhan Aibin. Environmental DNA (eDNA)-metabarcoding-based early monitoring and warning for invasive species in aquatic ecosystems [J]. Biodiv Sci, 2019, 27(5): 491-504.
[8] Shao Xinning, Song Dazhao, Huang Qiaowen, Li Sheng, Yao Meng. Fast surveys and molecular diet analysis of carnivores based on fecal DNA and metabarcoding [J]. Biodiv Sci, 2019, 27(5): 543-556.
[9] Zhu Baijing, Xue Jingrong, Xia Rong, Jin Miaomiao, Wu You, Tian Shanyi, Chen Xiaoyun, Liu Manqiang, Hu Feng. Effect of soil nematode functional guilds on plant growth and aboveground herbivores [J]. Biodiv Sci, 2019, 27(4): 409-418.
[10] Ma Yanjie, He Haopeng, Shen Wenjing, Liu Biao, Xue Kun. Effects of transgenic maize on arthropod diversity [J]. Biodiv Sci, 2019, 27(4): 419-432.
[11] Zhao Yang,Wen Yuanyuan. Development of Convention on Biological Diversity’s Global Platform for Business & Biodiversity: Policy suggestion for China [J]. Biodiv Sci, 2019, 27(3): 339-346.
[12] Qian Haiyuan,Yu Jianping,Shen Xiaoli,Ding Ping,Li Sheng. Diversity and composition of birds in the Qianjiangyuan National Park pilot [J]. Biodiv Sci, 2019, 27(1): 76-80.
[13] Dai Yunchuan,Xue Yadong,Zhang Yunyi,Li Diqiang. Summary comments on assessment methods of ecosystem integrity for national parks [J]. Biodiv Sci, 2019, 27(1): 104-113.
[14] Xueming Lei,Fangfang Shen,Xuechen Lei,Wenfei Liu,Honglang Duan,Houbao Fan,Jianping Wu. Assessing influence of simulated canopy nitrogen deposition and understory removal on soil microbial community structure in a Cunninghamia lanceolata plantation [J]. Biodiv Sci, 2018, 26(9): 962-971.
[15] Anrong Liu,Teng Yang,Wei Xu,Zijian Shangguan,Jinzhou Wang,Huiying Liu,Yu Shi,Haiyan Chu,Jin-Sheng He. Status, issues and prospects of belowground biodiversity on the Tibetan alpine grassland [J]. Biodiv Sci, 2018, 26(9): 972-987.
Full text



[1] LI Wei, ZHANG Ya-Li, HU Yuan-Yuan, YANG Mei-Sen, WU Jie, and ZHANG Wang-Feng. Research on the photoprotection and photosynthesis characteristics of young cotton leaves under field conditions[J]. Chin J Plan Ecolo, 2012, 36(7): 662 -670 .
[2] Li Zhong-Ming. Palaeosmunda Emended and Two New Species[J]. J Syst Evol, 1983, 21(2): 153 -160 .
[3] Yefei Shang, Ming Li, Bo Ding, Hao Niu, Zhenning Yang, Xiaoqiang Chen, Gaoyi Cao, Xiaodong Xie. Advances in Auxin Regulation of Plant Stomatal Development[J]. Chin Bull Bot, 2017, 52(2): 235 -240 .
[4] Li Shuzhong. Brief iutroduction on the success of captvie breeding of rare birds in the Beijing Zoo[J]. Biodiv Sci, 1994, 02(3): 181 -183 .
[5] Fu-Min Wang, Jing-Feng Huang and Xiu-Zhen Wang. Identification of Optimal Hyperspectral Bands for Estimation of Rice Biophysical Parameters[J]. J Integr Plant Biol, 2008, 50(3): 291 -299 .
[6] Tao Yan, Tiantian Qu, Huanhuan Song, Philippe Ciais, Shilong Piao, Zhenzhong Sun and Hui Zeng. Contrasting effects of N addition on the N and P status of understory vegetation in plantations of sapling and mature Larix principis-rupprechtii[J]. J Plant Ecol, 2018, 11(6): 843 -852 .
[7] Li Linghao. Effects of Land-use Change on Soil Carbon Storage in Grassland Ecosystems[J]. Chin J Plan Ecolo, 1998, 22(4): 300 -302 .
[8] . [J]. Chin Bull Bot, 2002, 19(01): 121 -124 .
[9] Brett J. Ferguson, Arief Indrasumunar, Satomi Hayashi, Meng-Han Lin, Yu-Hsiang Lin, Dugald E. Reid and Peter M. Gresshoff. Molecular Analysis of Legume Nodule Development and Autoregulation[J]. J Integr Plant Biol, 2010, 52(1): 61 -76 .
[10] CHANG Chen-Hui,WU Fu-Zhong,YANG Wan-Qin,TAN Bo,XIAO Sa,LI Jun,GOU Xiao-Lin. Changes in log quality at different decay stages in an alpine forest[J]. Chin J Plan Ecolo, 2015, 39(1): 14 -22 .