We taught a few people to build trees before we left the profession. Here's some contact information if you are looking for a custom, hand made tree.
This is definitely the best method we have found to communicate horse back shape over distance.
Here's a few links to good illustrations and/or information about anatomy. Enjoy!
This is where the great illustrations in the videos come from.
This illustrator has some neat illustrations of the equine skeleton, the superficial muscles, and the deep muscles of the horse. She also has some of the hoof and other equine joints, so the site is worth exploring.
Here's a whole anatomy book available on the web!
Here's a 46 minute video produced in Britain showing a partial dissection of a horse, emphasizing the things that allow them to be such incredible athletes.
He has books that teach you how to put some skeletons together. No horse, unfortunately, but some other mammals are close enough to get the basics.
This guy sells whole skeletons, but even if you don't want to buy, his pictures are fun to look at.
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