A Leonardo da Vinci drawing long thought to show the anatomy of a horse’s trunk probably depicts a dog, according to researchers.
The drawing, held by the Royal Collection Trust in Britain, was among a series of bear and horse drawings examined by Matilde Lombardero and María del Mar Yllera, who are with the University of Santiago de Compostela in Spain.
The pair, in the university’s Unit of Veterinary Anatomy and Embryology, unearthed a few other surprises, including an illustration said to be “the left leg and foot of a bear”, which in fact is most likely a bear’s right pelvic limb.
Da Vinci was an outstanding artist of the Renaissance. He was an expert painter, engineer and anatomist who produced thousands of drawings.
His interest in anatomy was overwhelming, proven by the many sheets dedicated to his anatomical studies, with abundant notes and drawings.
It is well known that da Vinci dissected numerous animals. As a result, many endeavours have been made to identify the animals depicted.
“In some cases, such identification is easy, while in others it is impossible,” the pair wrote in the open-access journal, Animals.
Most of da Vinci’s anatomical drawings are held in Britain by the trust. Previous access to the collection has been highly restricted, but nowadays it offers free access to these drawings in high resolution on its website.
Writing in the mid-sixteenth century, the biographer Giorgio Vasari stated that da Vinci compiled a treatise on the anatomy of the horse. However, it was lost when Milan was invaded by French forces in 1499. Soon after, Leonardo left the city and returned to Florence.
One drawing of the viscera of a large quadruped, thought to be a horse, is said to survive from this period, suggesting that Leonardo conducted full dissections to investigate the internal anatomy of the beast.
This drawing, labelled RCIN 919097-recto, is entitled The viscera of a horse and is under the care of the trust.
It is described in the collection as “an anterior view of the arteries, veins and the genito-urinary system of an animal, probably a horse,” implying that da Vinci did not name the drawing.
The drawing represents an underside view of the trunk of an animal, with the lungs, esophagus, stomach and intestines removed. The major blood vessels are clearly depicted.
The layout of the major blood vessels rules out the possibility that it depicts a horse, according to the researchers.
The pair studied further elements of the drawing. They said most of the anatomical elements are consistent with the open chest, abdomen and pelvis of a carnivore, probably a dog rather than a cat.
Continuing with horses, Leonardo da Vinci also drew some sketches comparing horse and human anatomy in terms of the pelvic limbs and legs, both standing and walking forward.
Da Vinci made an astute note: “To match the bone structure of a horse with that of a man you will have to draw the man on tip-toe”.
Leonardo da Vinci’s Animal Anatomy: Bear and Horse Drawings Revisited
Matilde Lombardero and María del Mar Yllera
Animals 2019, 9(7), 435; https://doi.org/10.3390/ani9070435