[Ecoed] food web diagrams follow-up

[Kristen Lennon]

Hi All,

I want to thank the many of you who responded to my question about the
arrows in food web diagrams. I greatly appreciate your input. It's
important to me that when I'm making recommendations to teachers at a
national level that I'm not making them based only on what I think is
correct. Eventually someone out there would catch my mistake, but I'd
rather get the advice of a large number of experts before-hand.

Just a quick follow-up question. Most of you (I've got 11 responses so
far) exclusively focused on the arrows as representations of the flow of
energy. In at least middle school students, there is a very strong
misconception that food IS energy or is solely a source of energy, not
that it is a source of the matter that makes up an organism's body. When
thinking about the two together - food as a source of energy and matter
- would you recommend emphasizing that when we talk about energy, it is
flow, and when we talk about matter, it is cycling? Any thoughts on how
younger students (middle school) might deal with this type of
distinction? We are dealing with this at a substance level, not a
molecular or atomic level, so cycling is difficult to address.

Thanks again for your input. This listserve (and the plant ed one) is
such a great way to connect with experts and educators.

Best,
Kristen

Kristen A. Lennon, Ph.D.
Research Associate
Project 2061
American Association for the Advancement of Science
1200 New York Ave., NW
Washington, DC 20005 USA


Tel:202-326-7032
E-mail: klennon at aaas.org
http://project2061.aaas.org