32 ORIGIN OF LIFE IN AMERICA 



being part of the indigenous fauna, yet we recognise that their 

 ancestors must have entered the continent from Asia in com- 

 paratively recent geological times. 



Let us take for example the moose deer (Alces americanus). 

 Its range extends from, Bering Strait, in a broad tract of forest 

 land eastward, along the northern shores of the Great Lakes 

 as far as Nova Scotia on the Gulf of St. Lawrence. Only 

 along the Rocky Mountains, as Mr. Thompson Seton has so 

 clearly indicated in his map of the range (Fig. 3), does the 

 moose occur further south.* 



There are a few historical records, and also some fossil 

 ones, which indicate that the moose once penetrated further 

 into the United States in various directions, but it evidently 

 never diverged very much from its present range. f The bones 

 of a couple of closely allied animals have been met with in the 

 Pleistocene deposits of Washington territory, and the, skeleton 

 of a peculiar moose, somewhat resembling the Alaskan variety, 

 has been discovered in the Pleistocene of New Jersey, and 

 placed by Professor Scott into a distinct genus (Cervalces). 

 Whether this animal was ancestral to the living moose, as 

 has been suggested, or whether it represents an aberrant 

 type which, has come in from Siberia with the moose, as Mr. 

 Grant seems to think likely, are problems which may be 

 left to future research es.J Certain it is that when we cross 

 Bering Strait into Northern Asia, we meet with a moose 

 (Alces bedfordiae) which in its simple antlers somewhat 

 resembles the young 'American moose. Further west as far as 

 Scandinavia, we find another species (A. machlis) differing 

 but slightly from Alces americanus. It seems almost as if 

 the moose had originated in eastern Asia from some more 

 generalised type like Alces bedfordiae, and had gradually 

 produced the forms with more palmated antlers in America 

 and Europe by a process of convergent evolution. In any 

 case, we are led to assume that Bering Strait was dry land 

 when the ancestors of the existing moose entered the New 

 World. Even if we suppose the moose to have originated in 

 America, a land bridge connecting the latter with Asia was a 



* Seton, Thompson, "Life Histories of Northern Animals,!.," p. 151. 



t Grant, Madison, "Moose." 



| Grant, Madison, " Origin and Belation of Mammals," p. 23. 



