SUMMARY: Donkeys and horses evolved to live in different climates. Donkeys are more adapted to dry, hot areas while horses are able to live in colder climates. Researchers looked at the difference in seasonal hair growth of donkeys, horses, and mules to see how each species adjusted to changing temperatures. Results showed that donkeys may be tough, but they are not well suited to live in colder climates because they weren’t able to grow a winter coat like horses (the study quantified “winter coat” in terms of hair weight, length, and width). Being hybrids, mules grew an intermediate winter coat. Horses were best suited for winter weather.
LESSON COMMENTS: This is a short and easy article to read. The experiment is simple, the graphs are easy to understand, and the content does not contain any technical jargon. This would be a great article during a chapter on thermodynamics, especially for younger students. Teachers can use the experiment as an example before allowing students to design their own experiments on insulation and heat transfer. The fact that the article is about horses and donkeys is a fun way to present the concept of thermodynamics to students.
Osthaus, B., Proops, L., Long, S., Bell, N., Hayday, K., & Burden, F. (2018). Hair coat properties of donkeys, mules and horses in a temperate climate. Equine veterinary journal, 50(3), 339–342. doi:10.1111/evj.12775