This is the walk cycle of a Llama, the video was shot in Noah's Ark Zoo farm near Bristol. It is quite a long sequence of images, as the animal has four legs to move... The sequence shows a full walk cycle, the last three images are at about the same point as the first three, so the actual cycle lasts 30 frames. The footage was shot at 25 frames per seconds, so 30 frames means a little bit more than a second. The animal was walking in a relaxed normal speed. To be able to analyse the movement clearer I've added coloured dots to the picture where the feet meet the ground.
If we look at the right back leg and follow it's movement we can see that it takes 13 frames for it to take a full step. About half a second. Of course this would change if the animal was walking faster or slower. More interesting maybe is to look at how the different legs are moved in relation to each other. We can see that in this 'normal' walk cycle the Llama always has either 2, 3 or 4 legs on the ground. Mainly 2 or 3, and when it has 4 at least one of those will be uplifted to the toe, about to take off.
This walk cycle starts where the Front Left and Back Left leg are lifted, the BL leg lands first and 5 frames later the FL leg touches the ground, at which point the Back Right leg is lifted. When the Back Right leg is half way (in stride position with the BL leg) the Front Right leg is lifted. Again now the BR leg touches the ground first (8 frames later), and 5 frames later the FR leg has also landed. At this point the BR leg starts to take off, and where it is in stride position with the BL leg again the FL leg is lifted.
In short the order of the legs moving:
FL --> BL --> FR --> BR
So far that's only the movement of the legs, which is where the main action comes from, but of course it causes the entire body to move with it. This is more difficult to see in the pictures but is clearer in the actual video footage shown above. We can see here that every time when one of the front legs is moved forwards, also the head and neck is making a forward movement. The front and back of the body is moving up and down in terms: wherever under the body the leg is in a straight position the body will be higher then where a leg is bent. Of course, it all makes quite sense when you look at the anatomy of the animal and how all bones and muscles fit together, which seems therefore another important form of research to be able to animate in a naturalistic and convincing way.