A horse is a horse unless it's a Jackass

Bodhi and I were practicing puddle crossing yesterday and it brought me back to a subject that has come up again and again since I bought him. Are all horses the same with the only difference being individual variability or are there distinct behavioral differences in breeds?
I personally am on the fence on this one.
Behavior is genetically heritable. Variation in behvior can be genetically linked in many different instances within populations and also between closely related species. Some examples that come to mind are the prairie and mountain voles in the US. Although they are very closely related; one species is monogamous and one species is polygamous. This is thought to be linked to an expression of a gene which controls a hormone which is responsible for pair bonding and parental care. I remember hearing about a cuckoo where female preference is genetically heritable within this one species. Males learn the song of their host family (they are brood parasites) Females prefer males that sing the song of the host she is genetically wired to parisitize(ie she makes eggs that look like the host's). I am not sure if I am explaining this right but it is pretty cool stuff.

Horse breeds can be genetically tested for. At least some can. Behavior(as previously discussed) has a genetic component so logically horse breeds could genetically "carry" behaviors. Case and point are the naturally gated breeds. I do not know a lot about them but I am pretty sure that it is a behavior that some are born with and then perfected by training? Yes?

I think the problem comes in with what is a heritable behavior and what is not. An example is I do not think that ponies are more stubborn than horses. I have met way to many pleasant ponies and stubborn horses to believe this is an actual heritable trait. I think this is more of an effect of bad training or poor communication. Same with Thoroughbreds being more spooky or stupid. I have met far to many trail safe level headed thoroughbreds and way to many crazy reactive quarter horses in my day. Is it safe to say though that the "hot bloods" are more excitable? I think so. They probably have more fast twitch muscles than cold bloods(an interesting research avenue) along with a high set head. They have been selected to be quick and reactive. I think people need not shy away with associating behavioral traits with certain types or breeds of horse. After all this is why we created selective breeding! However I think people need to be more careful with what they are claiming is an inate genetically inherited behavior and what is a learned response.

Back to Bodhi. Teaching Bodhi to cross water made me think of years ago when I had attempted the same task with my Thoroughbred Velour. While Bodhi balked at the water until he was brave enough to test it with one foot Velour simply leaped over the puddle. Even with the tiniest puddle Bodhi never thought to even try and step over it instead he balked or tried to go around. I slowly assimilated Velour to water by making him cross the puddles over and over until a leap turned to a canter to a brisk trot and then to a walk. Bodhi methodically tested the water with both feet and slowly shuffled through the puddle. We repeated the process until he was satisfied that puddles are indeed safe to cross. I think that is a great example of what I want to get across. The breeds are different in their behaviors in that Velour was a leaper and Bodhi is more of a plodder. To say though that one is better at crossing water would be a false statement because that is just training. They both turned out to be pretty good with water!

I would love to hear other peoples ideas and hypothesis on the subject!