Response by Gabor Horvath to mvortoj on 6 November 2022

Dear mvortoj, thank you for your comment. You can read my answer below.

mvortoj wrote on 2 November 2022 at 19:51 GMT:

https://journals.plos.org...

Da Vinci's horse is trotting not walking - Posted by mvortoj on 02 Nov 2022 at 19:51 GMT

Da Vinci's horse is moving in a collected trot. Similar to the wikipedia picture of a collected trot. https://en.wikipedia.org/... You said: "As mentioned in my earlier response, in our paper we assumed that artists depicted walking quadrupeds." Fine. But you criticized the artist based on your incorrect assumption.

Answer by Gabor Horvath:

Below I refer to Figure 4 of our paper entitled

Gabor Horvath, Etelka Farkas, Ildiko Boncz, Miklos Blaho, Gyorgy Kriska (2012) Cavemen were better at depicting quadruped walking than modern artists: Erroneous walking illustrations in the fine arts from prehistory to today. Public Library of Science One (PLoS One) 7 (12): e49786 (10 pages, doi:10.1371/journal.pone.0049786) + supporting information
http://journals.plos.org/...

Figure 4: (A, B) An erroneous modern, pre-Muybridgean horse drawing (Leonardo da Vinci) (http://www.davincisketche...) fitting into the cell Eh of the walking matrix. (A) Picture of the graphic art. (B) Schematic drawing of the horse. (C, D) Two possible corrections of the horse: C keeps the postures of the hind legs and corrects the attitudes of the fore legs, thus falls into the cell Gh of the walking matrix. D, keeping the postures of the fore legs and correcting the attitudes of the hind legs, belongs to the cell Ee of the walking matrix.
(source: Horvath et al. 2012,
http://journals.plos.org/...)

Referring to

https://en.wikipedia.org/...
and
https://www.facebook.com/...

let us consider the following types of the horse’s trot being relevant for us:

Collected trot: A very engaged trot where most of the horse's weight is carried toward the hindquarters. The frame is compressed and the stride length is shorter than any of the other trots with the horse taking higher steps. The horse is lighter and more mobile in the collected trot.

Collected trot (source: https://en.wikipedia.org/...)

Park trot: Sometimes simply called a Trot in a given class and seen in saddle seat and fine harness classes for Saddlebreds, Arabians and Morgans. It is a showy, flashy trot with extreme elevation of the knees (forearm is horizontal or higher and the hind legs are extremely flexed). The head is held high and at times a horse may hollow its back and lose cadence in an attempt to achieve high action in front. The hindquarters must be engaged for it to be properly performed.

Park trot (source: https://en.wikipedia.org/...)

Piaffe and the Passage trots: Two variations of the trot are specially trained in advanced dressage horses: the Piaffe and the Passage. The Piaffe is essentially created by asking the horse to trot in place, with very little forward motion. The Passage (rhymes with "massage") is an exaggerated slow motion trot. Both require tremendous collection, careful training and considerable physical conditioning for a horse to perform.

Piaffe trot (source: https://en.wikipedia.org/...)

Passage trot (source: https://en.wikipedia.org/...)

The trot continium (source: https://www.facebook.com/...)

Comparing Figure 4A,B of Horvath et al. (2012) with the above pictures of the collected trot, park trot, piaffe trot and passage trot, it is clear that in the drawing of Leonardo da Vinci the motion of the horse may be either collected trot, or park trot, or piaffe trot.

However, all three trot types are completely unnatural and do not occur in the natural, normal motion of horses. These trot types are specially trained in advanced dressage, characterized by exaggerated slow forward motion, require tremendous collection, careful training and considerable physical conditioning for a horse to perform.

In our paper, we wrote the following about the drawing of Leonardo da Vinci and our analyses:

"On the basis of the leg attitudes Fig. 4A could, in principle, depict a trotting horse. However, because the fore legs of trotting horses are never lifted so high, and the angle between the femur and tarsus cannot be nearly 90o this should be a walking horse. This is evident from the series of pictures taken of trotting horses by Muybridge (1887), for example."

"We admit that, of course, in our present work there is some speculation, because we could not ask the prehistoric or modern artists why they have composed certain drawings and depicted quadrupeds in a particular way. We presented here an optimal and simple way to compare one aspect, namely the accuracy of quadrupeds in a walking mode of locomotion. In this respect, it was irrelevant whether the artists' intention was to show an animal in a natural or unnatural pose."

"Being paintings or sculptures, for instance, these are static poses of whatever motion the artists wanted to express, not necessarily a standard walk. Here we tried to study this problem as correctly as possible: We disregarded any hypothetical or speculative artistic aim, and compared the leg attitudes of quaruped walking depictions in the fine arts with those of the real walking gaits of horses. As results, we obtained raw numbers of the incorrect and correct artistic walking illustrations, from which our final message, the error rates were derived for different (prehistoric, pre- and post-Muybridgean) epochs. This is the maximum of what can scientifically be done in this topic."


On the basis of the above, we conclude: If Leonardo da Vinci intended to depict a horse unnaturally moving in collected, or park, or piaffe trot, his drawing is correct. If, however, he aimed to illustrate a naturally walking horse, his drawing is erroneous and can be corrected as seen in Figure 4C,D of Horvath et al. (2012), for example.

Sincerely yours: Gabor Horvath (corresponding author)

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Prof. GABOR HORVATH
Department of Biological Physics
Physical Institute
Faculty of Natural Sciences
Eotvos University
H-1117 Budapest, Pazmany setany 1
Hungary
e-mail: gh@arago.elte.hu
https://arago.elte.hu
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