Hybrid speciation

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Botanists have long believed that hybrid speciation is important, especially after chromosomal doubling (allopolyploidy). Until recently, hybridization was not thought to play a very constructive part in animal evolution. Now, new genetic evidence suggests that hybrid speciation, even without polyploidy, is more common in plants and also animals than we thought.

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Figure 1: Hybridization and the adaptive landscape.


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I thank C. Brochmann, K. Dasmahapatra, B. Husband, S. Knapp, M. Linares, J. Mavárez, A. Meyer, P. Nosil, S. Otto, C. Salazar and S. Turelli for discussions and comments. The work was supported, in part, by grants from NERC and the DEFRA Darwin Initiative programme.

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Correspondence to James Mallet.

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