Lincoln's Dog Fido

[Donna McCreary]

Based on Fido's photos, there appears to be a ridge on his back. I can not tell if this is an arch in his back due to his position, a shadow from the light, or an actual marking of a Rhodesian Ridgeback dog. I am not familiar enough with the breed to know when they came to America - or were able to mix with other dogs to create a non-pure bred dog.
Fido's ears and the shape of his face remind me of the American Foxhound, or a terrier breed. The dark spot on his back and side could be shadowing, or it could be the markings of a darker patch of hair - such as the Foxhound and the shepherd have. If I had to pick possible breeds that were in Fido's ancestry, I would choose, Labrador Retriever; Foxhound; and either a terrier or Rhodesian Ridgeback.

I am by no means an expert on dogs. It's just fun to guess.