Learn about where diseases come from. How are they spread? This episode examines a variety of emerging wildlife diseases, with an emphasis on the One Health concept. While some disease outbreaks may be “natural”, human behaviors and influences are adding additional pressure on wildlife and the landscape, and in the end, all of us – humans, wildlife, and the environment – are affected. Learn more about the field of emerging wildlife diseases and the continually evolving research on what those diseases tell us.  

In this activity on page 1 of the PDF, learners compare the relative sizes of biological objects (like DNA and bacteria) that can't be seen by the naked eye. Learners will be surprised to discover the range of sizes in the microscopic world. This activity can be followed up with a second activity, "What's in a microbe?", located on page 3 in the same resource.