Jack Russell Terriers...

...were originally bred by the Reverend Jack Russell in Devon, England.  Clergymen of the English country at the time were blessed with money and a lot of free time.  According to Bill Bryson in his recent book "At Home," this led to a lot of clergy putting their brains towards other pursuits aside from churchly responsibilities.  Some were mathematicians, others studied animals, some published novels, etc.  Jack Russell gave us a dog.

 

Bryson, Bill.  "At Home." 2010 Anchor Books, Random House.  New York, New York.