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You can follow a group of muscles -- the hypaxials, or epaxials, or hypobranchials, for example -- from one species (the shark) to another (the cat), and they're mostly the same. Mostly. There are some differences. When we crawled out of the water we needed to develop a new way to hear. Thus, some of the bones got recruited to become the malleus, incus, and stapes of the ear (there's a mnemonic for this, "My MA says my TA's IQ is SHit"), and the associated muscles now control the tension of the eardrum. Evolution is clever that way. Or at least lazy. Get used to that pattern, you'll see it a lot.

CVA bonus question time (this is a real question from a real CVA class, tho not mine). Gizmo is standing on the couch. Fido is sleeping peacefully on the floor. Assuming she wants to jump down next to Fido to try and eat his head, what muscles will she use, in order? Please list the muscle, origin, insertion, and action. Start from the first muscle used to begin the jump; end after she comes to rest standing on the floor (but before commencing craniophagy).

It helped me enormously to make up a chart of the muscles, along with their origin, insertion, action, group, innervation, and some sort of way to remember them. We only had to remember one origin, one insertion, and one action per muscle, so that made it relatively easy. Some muscles -- the acromiodeltoid, for example -- are named after their attachment points, which makes life easier. Others, well, you're on your own. Go ahead and learn the innervations now because you probably won't have time to learn them later.

If I still had that chart, I'd stick it online, because there isn't a good one available. Maybe I will anyway, if I get the time this summer. Check back. Other than the sheer number of them, the problem I had with muscles was making sure I could recognize them from different viewpoints. Quiz yourself with your cat in different positions. Even more importantly, quiz yourself with everyone else's cats (it's a good idea to swap cats with people for review), because they'll all be used in the exams.

Speaking of exams, the format of my lab exams, and those of every CVA class I've ever heard of: A bunch of stations are set up, each with a specimen. Each station has a few questions (ours had two per station). In most cases, there will be something pinned. For example, your cat might have a pin marked "A" in a muscle, and a pin marked "not A" in a muscle next to it, and the question might be "identify muscle A". Then again, it might be "give one origin and one action for muscle A", or "name a muscle with the same origin and insertion as muscle A" or even "name a shark muscle in the group homologous to the group of muscle A".

Our CVA class had a time limit per station; when the buzzer went off you had to move on. If that's you, and you don't know an answer, take notes and come back to it (either on paper, or if you're able to do so, by returning to the station later). Since there was no penalty for guessing in our class, a couple of times I made up muscle names based on the names of the attachment points, and got it right anyway.

It takes a lot of time to dissect the muscles. The goal is to isolate them and have them look like they do in the book (more or less. Books are 2D and that makes a huge difference). Between the two of us we probably spent well over 40 hours on muscle dissection. You'll probably screw up a lot, at least at first. Some things I learned in dissection:

• Use the scalpel as little as possible. Try the wedge tool with the curved tip, or the *closed* tips of the scissors. If you must use the scalpel, turn it over and use it carefully to scrape. Cut only as a very last resort.
• Younger cats can be pretty wimpy, and the muscle tissue looks a lot like fat or connective. The good news is once you do get the hang of dissecting them, and can tell the difference between muscle and everything else, the muscles are pretty easy to isolate.
• If you scrape the blade of your scalpel across it and it shreds, it's muscle. If it balls up, it's fat. If you grab it with your tweezers and it tents up and tears, it's fat or connective; get rid of it. Muscle will act like, well, meat when you grab it with the tweezers, and resist both the compression and the tension.
• If you need to fold back a muscle, cut through the fascia (an aponeurosis if you have to, but preferrably a tendon), not through the meat itself. A lot of muscles (such as the rhomboids) just fall apart if you cut through them.
• Speaking of rhomboids, watch that your cat's arms don't fall off as you root for the epaxials in the north hemisphere.
• Bring spare scalpel blades, you'll need them. The cheap ones dull absurdly quickly.

Mostly, it's about practice. If you're going to be taking CVA, it might not be a bad idea to start bringing home cheap hunks of meat and dissecting them. It won't quite be the same -- the fixative does make a difference -- but it's still good practice.