Multiple intercontinental dispersals shaped the distribution area of Hordeum (Poaceae)
Article first published online: 10 JAN 2006
Volume 169, Issue 3, pages 603–614, January 2006
How to Cite
Blattner, F. R. (2006), Multiple intercontinental dispersals shaped the distribution area of Hordeum (Poaceae). New Phytologist, 169: 603–614. doi: 10.1111/j.1469-8137.2005.01610.x
- Issue published online: 10 JAN 2006
- Article first published online: 10 JAN 2006
- Received: 19 August 2005 Accepted: 4 October 2005
- Hordeum (Poaceae;
- long-distance dispersal;
- • The grass genus Hordeum (Poaceae, Triticeae), comprising 31 species distributed in temperate and dry regions of the world, was analysed to determine the relative contributions of vicariance and long-distance dispersal to the extant distribution pattern of the genus.
- • Sequences from three nuclear regions (DMC1, EF-G and ITS) were combined and analysed phylogenetically for all diploid (20 species) and two tetraploid Hordeum species and the outgroup Psathyrostachys. Ages of clades within Hordeum were estimated using a penalized likelihood analysis of sequence divergence.
- • The sequence data resulted in an almost fully resolved phylogenetic tree that allowed the reconstruction of intrageneric migration routes. Hordeum evolved c. 12 million years ago in South-west Asia and spread into Europe and Central Asia. The colonization of the New World and South Africa involved at least six intercontinental exchanges during the last 4 million years (twice Eurasia–North America, North America–South America, twice South America–North America and Europe–South Africa).
- • Repeated long-distance dispersal between the northern and southern hemisphere were important colonization mechanisms in Hordeum.