LATE LAND CONNECTIONS IN THE NORTH ATLANTIC AREA 



77 



fauna of Baffin Island shows much more relationship to east Siberia than to 

 Greenland! 



As far as the Coleoptera of Iceland, Greenland, and Baffin Island are 

 concerned, the situation may be illustrated, somewhat roughly, in the 

 form of a map (see Fig. 2). It demonstrates the blocking effect west of Green- 

 land by Davis Strait, which may be regarded as the most effective faunal 

 barrier of the entire Circumpolar area (Lindroth, 1957, p. 264). 



Fig. 2. The Palaearctic and Nearctic elements of indigenous Coleoptera in Green- 

 land and adjacent areas. Black sectors = flightless forms. Size of circles in 

 proportion to number of taxa (from 1 to 11). (Data from Lindroth, 1957.) 



The distribution in the same area of Nearctic and Palearctic elements of 

 vascular plants (Fig. 3) gives less evidence because most plants are apparently 

 better suited than soil-animals to passive long-distance dispersal (Lindroth, 

 1960). But the principle remains the same: plants with low abihty of dispersal 

 are to a considerable degree blocked by Davis Strait; the Palearctic element of 

 Greenland includes proportionally more forms not adapted to long-distance 

 dispersal than does the Nearctic element of that island. 



This is, indeed, surprising, considering the geographical position of Green- 

 land. It is tempting to resort to the strong pressure of conventional thinking 

 and suppose that if Greenland had belonged to North America politically and 

 not only geographically, everybody would have noticed the strange composi- 

 tion of its fauna and flora. 



What ought to be expected is, indeed, that the long distance from Europe — 

 against prevailing winds! — could have been successfully conquered only by 

 organisms with extraordinary means of dispersal, whereas an immigration 



