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"

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