Smackdown: Why’didja do that? or a brief look at scientific illustration history.

by Diane T Sands

I was asked by a colleague who viewed the Wild Pig Smackdown,

As a person who has no background in scientific illustration, I am curious to know how these two really different drawings can be produced of the same species and be useful?

This is a great question. A fair amount of historical scientific illustration, particularly during the Age of Exploration (1450-1700), was completed as a record of existence. Many of the items being illustrated on expeditions had never before been seen by Europeans and served as a record of the great things discovered, often proving to the expedition funders that their money was not wasted. Natural history specimens preserved using alcohol, drying, tanning or other means can readily lose color, shape and 3-dimensional character. Illustration was the most expedient way of preserving posture and indicating natural coloration.

While we have no real provenance for the Cole image or why it was created, it appears to fall into the this-is-what-a-boar-looks-like/historical camp.

As time has progressed, illustration remains a useful tool. Illustrators are able to show multiple or uncommon views, and to emphasize characteristics that would not be obvious in a photograph - cutaways that show animal burrows underground, or the complete cycle from flower to fruit, for example. In the systematic literature, illustrations of the whole plant or animal are often supplanted or used in combination with close-ups of the physiological or morphological characteristics that make each species unique. This can include geographic area, dentition, genitalia, or pollen structure - all things not easily photographed. The following image is one visual example.

Penny, N. (2002) "Lacewings of Costa Rica" Proceedings of the California Academy of Sciences, vol. 52 no. 12. Image 117 by Diane T Sands. Images 118, 119 by Victoria Saxe*

As I researched Sus scrofa, I thought about why someone would call me up and ask me to illustrate this species today. I also thought about what was it about this species that most interested me. What had I learned that I could convey visually? I was struck by the fact that while there are subspecies of Sus scrofa that are often isolated by region (and thus considered distinct), for the most part, the main question was: are they wild or domesticated? Since wild pigs of one sort or another have been introduced - either accidentally or purposefully - on islands around the world, the answer often blurs.

Is there an absolute distinction between the wild boar and the domestic pig? In my preparatory research, I came across an article** that looked at this issue from the point of view of prehistory, and porcine remains of archaeological digs. The illustrations accompanying the article are primarily area maps, and graphs of statistical measurement metrics. While well done and highly informative, one does need to know a higher level of vocabulary and maths to get the picture. I asked myself how I might visually explain at least one difference between a wild and a feral population in a way that even a non-biologist would understand.

The result is here.

*Victoria Saxe

** Rowley-Conwy,P., U. Albarella, and K. Dobney (2012) Distinguishing Wild Boar from Domestic Pigs in Prehistory: A Review of Approaches and Recent Results Journal of World Prehistory Vol. 25(1),  Pages 1-44. http://www.springerlink.com/content/6446560r166488x7/abstract/?MUD=MP