Arabidopsis 1c Botiza, Romania 090613 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 1 N of Russel Glacier, E of Kangerlussuaq, Greenland 140702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 2 N of Russel Glacier, E of Kangerlussuaq, Greenland 140702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 3 N of Russel Glacier, E of Kangerlussuaq, Greenland 140702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 5 N of Russel Glacier, E of Kangerlussuaq, Greenland 140702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 7 N of Russel Glacier, E of Kangerlussuaq, Greenland 140702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 8 Sandflugtsdalen E Kangerlussuaq, Greenland 140702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenosa 10 Ljungby, Småland 140530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenosa 7 Ljungby, Småland 140530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenosa 8 Ljungby, Småland 140530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenosa 9 Ljungby, Småland 140530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis petraea 1 Sulheim-Glömsdal, Norway 820731 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis petraea 3 Sulheim-Glömsdal, Norway 820731 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 1 Österslöv, Skåne 960517 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 10 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 18 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 7 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 8 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 9 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 8 Bjärred, Sk 130527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 9 Bjärred, Sk 130527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis 1a Botiza, Romania 090613 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis 1b Botiza, Romania 090613 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 10 Kangerlussuaq, Greenland 140629 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 11 Kangerlussuaq, Greenland 140629 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 12 Kangerlussuaq, Greenland 140629 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 13 Kangerlussuaq, Greenland 140629 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 14 Kangerlussuaq, Greenland 140629 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 4 N of Russel Glacier, E of Kangerlussuaq, Greenland 140702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 6 N of Russel Glacier, E of Kangerlussuaq, Greenland 140702 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenicola 9 Kangerlussuaq, Greenland 140629 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenosa 1 Sollentuna, Uppland 970810 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenosa 2 Sollentuna, Uppland 970810 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenosa 3 Ljungby, Småland 140530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenosa 4 Ljungby, Småland 140530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenosa 5 Ljungby, Småland 140530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis arenosa 6 Ljungby, Småland 140530 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis halleri Zdiar, Slovakia 950629 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis petraea 2 Sulheim-Glömsdal, Norway 820731 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 12 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 13 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 16 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 17 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 2 Österslöv, Skåne 960517 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 3 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 4 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 5 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis suecica 6 Hässleholm railway station Sk 160528 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 1 Lund, Sk 080511 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 10 Östra Station, Stockholm 150526 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 11 Östra Station, Stockholm 150526 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 12 Östra Station, Stockholm 150526 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 13 Östra Station, Stockholm 150526 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 14 Östra Station, Stockholm 150526 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 2 Lund, Sk 080511 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 3 Lund, Sk 080511 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 4 Bjärred, Sk 130527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 5 Bjärred, Sk 130527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 6 Bjärred, Sk 130527 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).

Arabidopsis thaliana 7 Lund, Sk 080511 - Photo: Jan Thomas Johansson (© 2014 Jan Thomas Johansson).