Re: Dogs and interbreeding, the question before a Progressive Creationist, Day-Age (and even YECs who believe "kinds" of animals were taken on the ark), isn't just declaring an interbreeding hypothesis. Or, perhaps it is, if one believes God initially created many different "breeds" of dog who can create unique offspring together. A main question I see
for a PC person like myself (or any non-evolutionary person really) to investigate re: dogs (and this is like a "first step" to what Hugh is perhaps wanting to know in regards to going as far back as Miacids) would be:
Did God seed a number of initial dog "breeds" which then interbred, or did God create just one Canis lupus (which both 'grey wolves' and 'domesticated dogs' fall under) that then evolved other traits over time to provide our present-day wolves and wide variety of domesticated dogs.
Now this is about to get a whole lot interesting, because I'm also Traducian
(believing that like biology gets transmitted from parents to offspring to certain degrees, so too an inheritance of our spiritual or soul-ish nature). And, it would seem to me, like the soul can be affected by physical ailments, that the soul can also affect the physical, change brain chemistry, we can stop our natural inclination to do something, etc. (this is something secular scientists largely reject, it is believed the physical can only influence consciousness and not vice-versa in what is philosophically known as epiphenominalism
I'm just stating my beliefs here upfront, ok? Whether or not one agrees, I'm about to introduce something likely relevant to such. Which is, I stumbled across a documentary which seemed like something made for really odd "dog lovers". It was a PBS Nova documentary called "Dogs Decoded". In it, they have people try to raise wolves and foxes as domesticated animals.
The experiment has been running for more than a good 50 years. Wolves, they struggled to tame and had to release after several months. Foxes, there were approximately 1% on fox farms who didn't appear aggressive, which they took and raised domestically. By the third generation, in addition to loosing their aggression, foxes became as tame as domesticated dogs and even craved human companionship -- they'd adapted to have a new-found co-dependency upon humans. Then by I think 8th or 9th generation, something surprising happened, which was physical attributes started changing like floppier ears, shorter tails, and different coloured fur coats.
The video can be found here (I've fast-forwarded to the interesting bit fore-mentioned): https://youtu.be/HHtN3sprvo8?t=26m20s
I'm still yet to confirm the authenticity of actual study, I remain skeptical as this documentary seemed to try justify a lot of seemingly odd claims that dog owner "freaks" would make. Nonetheless, if true, then such is quite fascinating on so many levels.