Untitled - Universitetet i Oslo

Tabell 2. En sammenlikning av Finse-populasjoner av Draba cacuminum og Draba norveglca i de tre
karakterene som best skiller artene. (Fra Elven & Aarhus 1984.)
A comparison ot Finse populations of Draba cacuminum and Draba norvegica in the three charccters
which best separate the species. (After Elven & Aarhus 1984.)
Fruktstands-tett het
lnfrutescence density
Pedicel-vinkel, grader
Pedicel angles, degrees
Sku lpe-form (lengde:bredde)
Siliqua index (length:width)
calculated. This is less than e.g. the known
evolution rates in North American house
sparrows. The evolution of races in Norwegian
Papaver radicatum has been used as
one of the arguments for the occurrence of
unglaciated areas during Pleistocene. lt is
here indicated that the potential evolution
rates may have been underestimated.
Takk til Professor Eilif Dahl som i fruktbar uenighet
har kommentert og diskutert et utkast til denne
artikkelen.
Litteratur
Berg, R.Y. .1963. Disjunksjoner i Norges fjellflora
og de teorier som er framsatt til forklaring
av dem. Blyttia 21:133-177.
Dahl, E. 1946. On different types of unglaciated
areas during the ice ages and their
signif icance to phytogeography. New
Phytol. 45:225-242.
Biogeographic and geotogic indi-
-1955.
cations of unglaciated areas in Scandinavia
during the glacial ages. Bull. Geol. Soc.
America 66: 1499-1519.
Refugieproblemet
-1961. og de kvartergeologiske
metodene. Svensk Naturv. 14: g1-
96.
Plant migrations across the North
-1963.
Atlantic Ocean and their importance for
the paleogeography of the region. l: Lave,
A. & Love, D. (red.), North Ailantic biota
and their history, pp. 173-188. Oxford.
Danielsen, A. 1971. Skandinavias fjellflora i
lys av senkvart€r vegetasjonshistorie.
Blyttia 29: 183-209.
Elven, R. 1980. The Omnsbreen glacier nunataks
- a case study of plant immigration.
Norw. J. Bot. 27: 1-16.
40
D. cacuminum D. norvegica
(4.1-)6.4 (-8.8)
(35-) 48 (-61)
(2.1-\ 2.5 (-2.9)
-&
(1.7-) 3.0 (-4.3)
(1 1 -)
19 (-27)
(2.s-) 3.2 (-3.5)
Aarhus, A. 1984. A study of Draba cacu-
minum (Brassicaceae). Nord. J. Bot. 4:
425-441.
Eldredge, N. & Gould, S.J. 1972. Punctuated
equilibria: an alternative to phyletic gradu.
alism. l: Schopf, T.J.M. (red.), Modets in
paleobiology, pp. 82-115. San Francisco.
Fryer, G. & lles, T.D. 1969. Alternative routes
to evolutionary success as exhibited by
African cichlid f ishes of the genus Tilapia
and the species f locks of the Great Lakes.
Evolution 23: 359-369.
Futuyma, D.J. 1979. Evolutionary biology.
Massachusetts. 565 pp.
Fegri, K. 1963. Problems of immigration and
dispersal of the Scandinavian flora. l:
Love, A. & Love, D. (red.), North Ailantic
biota and their history, pp. 221-232. Oxford.
Gjerevoll, O. 1959. Overvintringsteoriens
stilling i dag. Kgl. Norske Vid. Setsk. Forh.
32: 36-71.
-1963. Survival of plants on nunataks in
Norway during the Pleistocene glaciation.
l: Lave, A. & Love, D. (red.), North Ailantic
biota and their history, pp.261-283. Ox-
ford.
Plantegeografi.
-1973.
Trondheim. 186 pp.
Grant, V. 1981 . Plant speciation. New york.
563 pp.
Hafsten, U. 1972. Plantegeograf i. Trondheim.
125 pp.
Haldane, J.B.S. 1949. Suggestions as to the
quantitative measurement of rates of evolution.
Evolution 3: 51-56.
Johnston, R.F. & Selander, R.K. 1964. House
sparrows: Rapid evolution of races in
North America. Science 144: 548-550.
Kimura, M. 1968. Evolutionary rates at the
molecuf ar level. Nature 217:624-626.
Knaben, G. 1954. Saxifraga osloensis n.sp.,