Other forms of quadrupedal locomotion

Cecil's Columns/Staff Reports
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In the column about the two ways dogs walk (http://www.straightdope.com/classics/a4_090.html), Cecil seems surprised at the answer. I just wanted to point out that there’s even more to it—the two methods for dogs are “pacing” and “trotting”, but there are a number of ways to move on four legs, all with technical names, and all fairly well studied at e.g. the MIT leg lab (http://www.ai.mit.edu/projects/leglab/). They are:

[ul][li]pacing (aka ambling): left and right sides move together—seen most often in camels and giraffes (and, apparently, dogs);[/li][li]trotting: diagonal legs move together;[/li][li]bounding: front legs move together, back legs move together;[/li][li]galloping: front legs almost together, back legs almost together;[/li][li]cantering: FL, then BR, then FR and BL together (or reversed);[/li][li]walking: all four legs hit the ground separately, in the order FL, BR, FR, BL;[/li]and last but not least, I’m not kidding,
[li]pronking: all four legs hit the ground at the same time. Seen in gazelles and young deer.[/ul][/li]
Also, Cecil omitted one of the most important reasons some animals pace instead of trotting: if the legs are long enough relative to the length of the trunk, trotting will cause the feet to bump into each other.

“Science without the humanities is aimless, but the humanities without science are groundless.” --anon

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That’s interesting. Thanks.

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blahedo, I believe that in horses, at least, a gallop and a canter are the same gait, differentiated by rate of speed. The sequence is necessary to maintain balance while providing impulsion. Is there a different gait in other four-legged animals referred to as a gallop?

Also, I believe the ‘amble’ refers to a different gait in horses - I’ll have to check on exactly what the sequence is.

Some days you’re the dog, some days you’re the hydrant.

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coosa, this was discussed in a prior thread here, and pacing and ambling are the same gait. You might try looking for the prior discussion using the search engine. :slight_smile:

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Thanks, DS, I looked up the thread. I also did a little research last night, and found a lot of confusion, even among horse people! Some referred to the canter and gallop as different gaits, some claimed they were the same gait. The difference seems to be that, while the legs move in the same sequence in both the canter and gallop, the extended stride of the gallop causes a discernable interval between the hoofbeats of the diagonal pair that strike the ground almost simultaneously.

However, I believe the amble/broken pace (also called the stepping pace, rack, foxtrot, singlefoot, paso, and toelt, among other names!) is a separate gait from the standard pace. In the pace, lateral pairs of legs leave and strike the ground virtually simultaneously, and there is a moment of suspension as in the diagonal trot.

In the amble/broken pace, there is always at least one foot on the ground supporting the animal - at slow speeds (walking speed), two or three legs may be in contact with the ground, while at faster speeds only one foot may be remain on the ground. This is supposed to be why the ride of ‘gaited’ horses is so much smoother than that of ‘non-gaited’ horses. At the faster gaits (trot/pace, canter/gallop) there is a moment of suspension followed by a jarring return to the ground - less severe in the canter/gallop, but that’s another whole discussion. A ‘gaited’ horse can be ridden at speeds comparable to a fast trot/pace without the same jarring effect.

I’ve been watching my cats walk around today, and they all use the amble/broken pace gait. (I need a video camera to record and analyze their faster gaits.) Coincidentally, I also recently received the latest copy of my breed newsletter which includes several frame-by-frame examples of domestic cats and an Asian Leopard Cat walking. (Exhbition of soundness through movement was the topic.) All of the cats exhibit this same gait.

The sequence at a slow walk is as follows:

Left hind pushes off and travels forward. The hind foot overreaches the position of the front foot, so just before the left hind touches down, the left front pushes off and begins traveling forward. Left hind touches down. Left front touches down. Right hind pushes off. Right front pushes off. Right hind touches down. Right front touches down. Left hind pushes off.

At various times, the cat is support by either three or two legs. However, at faster speeds, the right hind will push off before the left front touches down, or even before the left hind touches down. Apparently, gaited horse people refer to this as ‘walking in front, trotting behind’, because there is diagonal movement (left front and right hind traveling forward at same time)while the sequence of footfalls remains lateral.

This is not the same as a pace, in which lateral leg pairs move forward and back at the same time. The footfall sequence is always lateral - left hind, left front, right hand, right front - and a four-beat gait is maintained - no two feet strike the ground at the same time.

There is some controversy over whether this gait is natural or a result of training in horses (although breeders of gaited horses claim they observe young foals performing the gait), but it is certainly natural in cats.

Maybe the guys at MIT neglected to include any cats in their study?

Some days you’re the dog, some days you’re the hydrant.

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I checked out the MIT web site pretty thoroughly, and couldn’t find any of the definitions for gaits listed by blahedo anywhere - was this information perhaps included in the videos somewhere? Or did the definitions, etc. come from somewhere else?

If someone can provide a link or something where I can check this out, I would appreciate. I guess it’s pretty obvious I have some disagreement with the above definitions!

Some days you’re the dog, some days you’re the hydrant.

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I don’t have a link, but I do have a cite and quote that might help:
The Order of Things, Barbara Ann Kipfer, page 334:

So then, there are 2 noted differences between canter and gallop. (1) Canter has left fore and right hind simultaneous, while gallop has left fore then right hind and (2) In a gallop, after the right fore hits, all four hooves come off the ground.

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To be honest, they were mostly from memory; the MIT link was included (and dammit, the http:// was supposed to automatically be a link, I thought) because I knew they are/were doing research in it and it was from one of their videos that I learned most of it, along with discussion in a robots class I took. BUT, that said, here are a few links turned up by Google that seem to support my claims: [ul][li]http://www.wizvax.net/tap3x/EMBTI/j6couette.html (search for “gait”)[/li][li]http://www.cut-the-knot.com/books/natnum/[/li][li]http://www.equiworld.net/global/gaits/ (this has some nice animated GIFs, if you can slow them down enough)[/ul][/li]
HTH.

“Science without the humanities is aimless, but the humanities without science are groundless.” --anon

9

Wow, folks, I have a serious headache! I’ve been trying to find more info on ‘gaits’ on the internet (thanks for the links, blahedo - I had actually already visited a couple of those).

One thing that appears obvious is that there is a lot of disagreement about what constitutes a ‘gait’. Some differences are obvious, as between a walk, a trot, a pace, and a canter. However, speed and individual characteristics affect such things as timing between footfalls and the supportive legs, and the line between separate gaits can be awfully blurred. For example, the equine canter and gallop are considered by some to be the same gait at different speeds, and considered to be separate gaits by others. While the sequence of leg movements is identical in both cases, the slower, more compressed canter results in the diagonal pair of feet striking the ground at virtually the same time, giving a three-beat cadence (left rear, right rear/left front, right front). When the horse increases speed into a gallop, the added extension of the movements results in the diagonal pairs striking the ground separately, giving a four-beat cadence (left rear, right rear, left front, right front).

BTW, I learned that this is called a ‘transverse gallop’ - dogs have a different galloping motion called a ‘rotary gallop’. (I also learned that llamas pronk.)

I found a really good web site with frame-by-frame photos of horses walking, ambling, trotting, pacing, cantering, galloping, and jumping. This site also supports my contention that the ‘amble’ and the ‘walk’ are not the same gait - the difference is clearly demonstrated in the photos. There are also a couple of examples of dogs galloping, but the pictures aren’t very good. Anyway, check out: http://bowlingsite.mcf.com/Movement/locoindex.html

Another interesting site similar to the MIT site has some cool MPEGs of computer animated animal motion. Has to be the ugliest excuse for a cat I’ve ever seen! But check out the furry quadraped jumping on a ramp and walking in tires at: www.dgp.toronto.edu/people/van/ani.html

And my cats think I’ve lost my mind! But I did discover that some of my cats ‘walk’ and some of my cats ‘amble’ - when they speed up, some of them pace and some of them trot. Typical cats - they all have to be different.

Some days you’re the dog, some days you’re the hydrant.

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Cats also bound, such as when you catch one where it knows it’s not supposed to be, and suddenly remembers an urgent appointment in China.

John W. Kennedy
“Compact is becoming contract; man only earns and pays.”
– Charles Williams