POLAK ORIGIN OF LIFE 23 



Strait alone. Mr. Emerton * makes mention of several 

 instances among spiders. 



Such cases can be traced among earth-worms, beetles, wood- 

 lice, ants and other groups. In some cases the identity or. 

 similarity of species occurring on the two continents may be 

 due to the fact that the species originated in Greenland or 

 some polar centre, no longer in existence, and subsequently 

 travelled in different directions towards their present habitat. 

 This conception, however, has very little in common with that 

 of a polar origin of life which was first mooted by Dr. Allen. f 

 He argued that the northern circumpolar lands may be looked 

 upon as the base or centre from which have spread all the 

 more recently developed forms of mammalian life. 



A few years later Dr. Haacke J directed attention to the 

 peculiar circumstance that the most primitive orders of 

 mammals and birds all have their living representatives 

 in outlying areas of the southern hemisphere, such as 

 Australia, New Zealand, Madagascar, South Africa and 

 South America, notwithstanding that these animals are 

 known to have formerly inhabited the northern hemis- 

 phere. This, he thinks, implies that a southward re- 

 treat has taken place of the more ancient forms before 

 the advancing host of higher orders of life. It would 

 seem, therefore, as if streams of more and more highly 

 specialized orders of mammals and birds had been slowly 

 evolved in the north and had constantly pressed the older ones 

 southward. -This suggested to Dr. Haacke the idea of a polar 

 continent from which the various orders had gradually been 

 distributed across the continents. Dr. Wilser even assumes 

 a polar origin for man. 



A similar theory was pronounced by Canon Tristram || in 

 explanation of the present distribution of the higher groups of 

 birds and their migrations. The migratory instinct, he con- 

 tended, was due to their having originated in a polar centre 



* Emerton, J. H., "Spiders common to New England and Europe," 

 p. 129. 



t Allen, J. A., "Geographical Distribution of Mammals," p. 37o. 



I Haacke, W., " Nordpol als Schopfungszentrum." 



Wilser, L., " Der Nordische Schopfungsherd," p. 134. 



|| Tristram, H. B., "Polar Origin of Life." 



