The Challenge of Experiments. Dr. Gard W. Otis Department of Environmental Biology. My Rules as an Instructor:. Treat students as individuals Make content interesting : students will learn! Treat students with respect Give meaningful assignments
Dr. Gard W. Otis
“Investigation of the behaviour of insects within an ecological and evolutionary framework. Topics range from basic behavioural principles to the complex behaviour exhibited by social insects.”
Course Assignments (in ~1999)
► Behavioural observation assignment (30 Qs)
► Term Paper
► Midterm Exam
► Final Exam
(aka 30 Questions)
2002: Learning by Assassin Bug Predators of Unpalatable Aposematic Insects
Platymeris bigutatta, large African assassin bug (Toronto Zoo)
Oncopeltus fasciatus, the milkweed bug (commercial sunflower-feeding strain)
Unpalatable: consumed milkweed seeds (+toxins) throughout development: aposematic colouration
Palatable: consumed sunflower seeds (no toxins) throughout development: perfect “Batesian” mimic
(1)learn to avoid unpalatable prey?
(2) intrinsically avoid aposematic prey?
Aposematic Cryptic Aposematic Cryptic
Assasin bugs were given one prey type for 6 days, then other type of same palatability, different colour
Feeding duration (violent rejection of unpalatable prey):
Unpalatable prey, ~2 sec; palatable prey, ~ 19.4 min!
Milkweed toxins are effective in deterring predation.
Number of prey captured:
1-2 unpalatable prey; many palatable prey (avg. 3.8)
Assasin bug predators learn to avoid unpalatable prey!
Time to attack:
greater for aposematic prey than for cryptic prey!
Evidence for innate response to aposematic prey!!!
If you took the course again, would you prefer to do an experiment again or write a term paper? 15/15 in favour of experiment!!!
“The experiment was a great change from the rest of my biology courses, where ‘lab’ usually meant examining dead things or doing computer modeling. Having the opportunity to actually go through the process of scientific enquiry (and not just learn how to) was extremely beneficial.”
“Until the project that we did in Insect Behaviour, every hands-on experiment that I had done in university was merely a replication of an experiment done many years prior, the results of which were already common knowledge in science. This was the first time that the end result was actually unknown to us and it was exciting to think that our undergraduate class may actually contribute something new to science. It was also a really valuable experience to go through the scientific process from the very beginning, brainstorming with each other about the best methods and materials to use in order to best test our hypothesis.” J.M.
“Few courses offer true learning experiences. Most seem to limit their scope to class papers. While (hopefully) interesting and useful, they are more a test of how good students are at utilizing library resources and regurgitating them into new and unique text. Your theory of bug-bug defense strategies was a unique one which opened our eyes to the actual world of scientific discovery, where the final result is a huge question mark and not something that can simply be looked up ahead of time. I had my first opportunity to really get into the nitty-gritty of organizing and implementing a novel study. It’s pathetic that undergraduate students aren’t faced with more material like this.” K.K.
“The only drawback I recall had to do with the issues of integrating the ideas of a large group. As I recall, there were a lot of good ideas as to how to run the experiment but when we tried to mesh them together, it produced a design that was not as neat as it could have been.” K.A.
“Normally I would dissuade anyone from doing a group assignment. I’ve had nothing but problems dealing with fellow students. Luckily I had a fantastic group for this experiment and for once, the entire class seemed revved up.” K.K.
“I can’t remember most of my term papers, but I do remember the entire process of our assassin bug learning experiment. From hashing out all the details in seminars, meeting with my group, and watching the assassin bugs toss the milkweed bugs across the plastic containers! C. T.
“What better way to teach future scientists about the methods than to throw them through it once, with all of the uncertainty, errors, time constraints, budget constraints and general adversity that faces real experimentation. D.C.
“Years later, I marvel at how your course influenced my life long learning objectives. Every time there’s a BBC nature special or an interesting insect news story or a client find unwanted pests in the greenhouse, I find myself pondering questions as if back in class worrying about my assassin bugs!