Taming a Dog

I've known about cats a lot longer than I've known about dogs.  But I could never manage to catch a cat. I'd get hearts for feeding them and everything but they would never follow me.  So imagine my surprise yesterday when I captured a wolf and made it into a dog by smacking it with a bone. (Use left click because right click will kill it).  I had it for a while then lost it when it was attacked by a mob of spiders. But straight away I got another one, and so far I still have it.  I even died once, and assumed it would also vanish, but it was still there when I respawned.  In my current scenario, which I called Botanica, I haven't even seen a cat yet.