A matter of time
Under the covers
Patricia Yang, from Georgia Institute of Technology, talks to us about the surprising science of poo.
Patricia: During a previous study on urination, we accidentally captured a video of an elephant defecating. This led us into a debate as to which animals’ faeces deformed, and which didn’t. We did some literature research and realised that although this is an important question, no-one had ever asked it
We therefore decided to study defecation in a wide range of animals, from cats to elephants. We took a collection of animal defecation videos and made an interesting discovery: all animals defecate over roughly the same duration – around 5–20 seconds.
This is possible because of a thin layer of mucus coating on the surface of faeces in the rectum. Large animals have not only more faeces to defecate but also thicker mucus layers than those of small animals. The faeces slide down along the rectum by a layer of mucus.
This study could help to diagnose gastrointestinal ailments non-invasively by measuring defecation time.
From the art desk
Patricia: When we started exploring a cover image, I immediately thought of my best friend Wan-Ting Huang, who is an artist and whom I have known for over 20 years.
Wan-Ting: Scientific research is fascinating to a wide audience, but for a layman, it could also easily come across as esoteric and serious. I aimed to design a cover that would paint Patricia’s research with a layman’s brush, so that everyone gets to enjoy the magic behind her findings!
The illustration portrays the concept that most of mammals actually spend a fairly similar amount of time defecating regardless of their physical size.
I wanted a simple concept that would be easy to grasp, and after exploring a few ideas 'toilet' came to mind as a more elegant symbol to represent faeces.
With the trickiest challenge solved, I then added other touches like the clocks (symbol of time) and the animal footprints (symbol of mammals) to complete the whole story.
I started with hand-sketches for initial exploration, and then moved to digital as the idea took shape. I produced the final illustration by Adobe Illustrator, a digital illustration tool.
Read the article
Patricia Yang et al, Soft Matter, 2017, DOI: 10.1039/ C6SM02795D
This image appears on the cover of Soft Matter, 2017, Issue 29.
Press office
- Tel:
- +44 (0) 20 7440 3351
- Email:
- Send us an email
Soft Matter
- Email:
- Send us an email