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St. Bernard
Eskimo
Poodle
Dachshund
German mastiff
English bloodhound
Pointer
Bulldog
Greyhound
Newfoundland
Shepherd
Spitz
Fig. 408.—Artificial Selection. Its effects in causing varieties in one species. Which of the dogs is specialized for speed? Driving cattle? Stopping cattle? Trailing by scent? Finding game? Drawing vehicles? Going into holes? House pet? Cold weather? In Mexico there is a hairless dog specialized for hot climates. The widely differing environments under various forms of domestication cause "sports" which breeders are quick to take advantage of when wishing to develop new varieties. Professor De Vries by cultivating American evening primroses in Europe has shown that a sudden change of environment may cause not only varieties but new species to arise.
