Table 1.

Mating system in long-distance colonizing plants in the remote Svalbard Archipelago in the arctic

	Empetrum nigrum	Vaccinium uliginosum	Rubus chamaemorus	Betula nana	Dryas octopela	Salix herbacea	Cassiope tetragona	Arabis alpine	Saxifraga rivularis
Main dispersal vector	Bird	Bird	Bird	Wind	Wind	Wind	Wind?	Wind?	Wind?
Minimum no. of propagules	7	12	6	11	38	20	14	1	22
Mating system	Dioecy	Selfer	Dioecy	Allogamous (self-incompatible)	Allogamous (self-incompatible)	Dioecious	Allogamous (?)	Mixed selfer	Autogamous (occasional outcrossing)
Reference	Bell and Tallis (1973)	Jacquemart and Thompson (1996)	Taylor (1971)	BiolFlor database	BiolFlor database	BiolFlor database	http://www.binran.ru/	BiolFlor database	Senstad Guldahl et al. (2005)

Long-distance past colonization was estimated by inferring the most likely sources of colonizers on the continent using DNA fingerprinting. The predominant source is north-western Russia, i.e. the most distant regions. The minimum number of colonizers was calculated as the smallest sample needed to observe genetic diversity on Svalbard. I mapped mating system for the nine species from the literature (see Reference).