The aim of this exercise is to start with a found image but then build on it to create something more personal. Find scientific and biological sources for animal anatomy; look for images that clearly show the mechanics of different animal’s bodies. Copy interesting images loosely, but make them into something more than a replica of someone else’s work by adding your own touches. Think about the parts that make up the whole, and about movement and stillness, emotion and detachment.
Use your compositional skills to position the subject within a believable scenario or space. Think about negative and positive space, measuring, gestural and expressive line to help you create more interesting drawings.
I decided that I wanted to draw something based on the anatomy of the horse. As a biomechanist I am very interested in mammalian locomotion and spend many years researching the mechanical properties of tendons and their roles as biological springs. I decided I wanted to add these mechanical devices to a drawing of a live animal. My found image had to be of quite a specific pose: I wanted an image that showed a horse galloping at the point of set down of one back leg. This is not the way horses are depicted in anatomy books so I resorted to searching the internet for found photographs. I found one image suitable for my needs – ‘Silver Horse’ from http://miriadna.com/preview/silver-horse a site that allows you to download this image for use as a computer wallpaper. I reversed this found image so the horse was moving from right to left. Using a large (a bit bigger than A2) beige pastel paper I made a pencil sketch of the outline of the horse with very slight shading to show the main limb muscles evident in this pose. I used Skerritt and McLelland (1984) as a reference text to work out important landmarks : bones, muscles and tendons on my image. (I ended up altering the right foreleg hoof after this photo was taken. I had heard hooves were very difficult to draw – they most certainly are!)
Once the pencil drawing was done I set about adding three detailed parts to my drawing using coloured pencil in a way that I hoped would look like I had stripped away some of the skin to see inside:
Firstly I drew in the large hindlimb muscle the biceps femoris (part of the hamstring group). Its main (but not exclusive) actions are to flex the hip and stifle and it provides much of the power in a galloping horse. I used a red/brown coloured pencil to draw represent directional lines of muscle fibres of this fan-shaped muscle.
Secondly I ‘stripped’ away the skin over the left hind cannon bone and added a spring in coloured pencil, overlayed by conte crayon. The tendons from the deep-digital flexor muscles situated higher up the leg are arranged in such as way as to act as springs during locomotion. As the foot is placed on the ground the tendons are stretched and put under great tension. When unloaded the tendons recoil in a manner similar to an elastic band. I thought that the stretching of an elastic band would be hard depict here, however, energy is conserved in a way similar to that conserved with the recoil of a compressed spring of a child’s pogo stick. As the scientific community refers to tendons that act in this way as biological springs, I decided to show this energy conservation mechanism as a coiled spring.
Thirdly, I added a spring at the position of the biceps brachii on the fused radius/ulna of the foreleg. This spring acts in a slightly different way to that found in the hindlimb. Rather than storing elastic strain energy that is returned to reduce the cost of locomotion, this spring stores energy and releases it is away that allows a horse to move its legs faster. As a horse is galloping the muscle and its associated connective tissues are stretched as the leg is straightened and is load-bearing. Contraction of the biceps brachii is important in flexing the elbow joint which enables the limb to be drawn up and forward in preparation for the next stride. When a horse is travelling at speed however, the muscle on its own can not contract fast enough to cycle the limb through the air in time for the next stride. The recoil of the spring provided by the stretched tendons and connective tissues associated with the muscle act as a catapult, propelling the leg upwards and forwards enabling the horse to cycle its legs faster than it would if relying on muscle contraction alone.
Finally having positioned my three areas of detail I used white and dark grey conté crayons and soft pastels to add an area of skin texture around each window. I wanted to show some surface detail that would draw your eye to the areas of interest rather than make it look like an unfinished drawing!
I am pleased with the concept and the results but there are areas that I struggled with. I feel the initial pencil drawing became a little over worked especially around the feet and the head. The surface detail around the exposed muscle was very hard to get right as well, the contours of the other muscles show through the skin but with the section missing it was hard to make them into a coherent muscle pattern. As a result this area became overworked too. I also struggled to work out what to do with the background. I didn’t want anything that would detract from the areas of mechanical interest. I ended up just putting in a horizon line which was really a cop-out! I did toy with the idea of blending some muted shades of grey and white pastel behind the horse (possibly the head) but I couldn’t see where I was going with this idea beyond doing it for the sake of doing it, so I have left it as it is. Any suggestions?
Skerritt, G. C., and McLelland, J. (1984) An Introduction to the Functional Anatomy of the Limbs of the Domestic Animals. Wright: Bristol