1. Knowing your own: A classroom case study using the scientific method to investigate how American coots recognize their offspring Joanna K. Hubbard, Daizaburo Shizuka, Brian A. Couch

2. Learning Objectives 1.Identify and describe the steps of the scientific method 2.Develop hypotheses and predictions 3.Construct and interpret bar graphs based on data and predictions 4.Draw conclusions from data presented in graphical form

3. The Scientific Method Observation Question Background Knowledge Hypothesis Experiment: Make Predictions Analyze Results Conclusion

4. OBSERVATION: What is happening? Video of coot adult harassing chick (video 4): http://www.nature.com/nature/journal/v463/ n7278/suppinfo/nature08655

5. American Coot Brood Parasitism Mom and Chicks: https://upload.wikimedia.org/wikipedia/commons/9/92/Mother_American_Coot_and_chicks_in_nest.jpghttps://upload.wikimedia.org/wikipedia/commons/9/92/Mother_American_Coot_and_chicks_in_nest.jpg Nest: https://upload.wikimedia.org/wikipedia/commons/9/98/Eurasian_Coot_nest_and_eggs.jpghttps://upload.wikimedia.org/wikipedia/commons/9/98/Eurasian_Coot_nest_and_eggs.jpg

6. Parasitism: Exploiting other organisms Ticks Lice ‘Zombie Ants’ Parasitic fungus Tick: https://upload.wikimedia.org/wikipedia/commons/7/7d/Deer_Tick_-_geograph.org.uk_-_105508.jpghttps://upload.wikimedia.org/wikipedia/commons/7/7d/Deer_Tick_-_geograph.org.uk_-_105508.jpg Lice: https://upload.wikimedia.org/wikipedia/commons/d/d0/Bugbuster.jpghttps://upload.wikimedia.org/wikipedia/commons/d/d0/Bugbuster.jpg Ant: https://upload.wikimedia.org/wikipedia/commons/8/85/Ophiocordyceps_unilateralis.pnghttps://upload.wikimedia.org/wikipedia/commons/8/85/Ophiocordyceps_unilateralis.png

7. Brood Parasitism: Exploiting parental care Reed warbler feeding cuckoo nestling Wilsons warbler feeding cowbird fledgling American coot feeding chicks Cuckoo: https://upload.wikimedia.org/wikipedia/commons/5/5c/Reed_warbler_cuckoo.jpghttps://upload.wikimedia.org/wikipedia/commons/5/5c/Reed_warbler_cuckoo.jpg Cowbird: https://upload.wikimedia.org/wikipedia/commons/f/fb/Wilson%27s_Warbler_feeding_Brown-headed_Cowbird_%22offspring%22.jpghttps://upload.wikimedia.org/wikipedia/commons/f/fb/Wilson%27s_Warbler_feeding_Brown-headed_Cowbird_%22offspring%22.jpg Coot: https://upload.wikimedia.org/wikipedia/commons/9/9e/Fulica_americana4.jpghttps://upload.wikimedia.org/wikipedia/commons/9/9e/Fulica_americana4.jpg

8. QUESTION: How do parents know which chicks belong to them? Chicks: https://upload.wikimedia.org/wikipedia/commons/4/42/Fulica_americana_-Klamath_Falls%2C_Oregon%2C_USA_-chicks-8.jpghttps://upload.wikimedia.org/wikipedia/commons/4/42/Fulica_americana_-Klamath_Falls%2C_Oregon%2C_USA_-chicks-8.jpg

9. BACKGROUND KNOWLEDGE: What do we already know? Parents harass and reject parasitic chicks (video) The orange color in coot chick heads is variable Chicks hatch over the course of several days Parasitic chicks typically hatch later than the chicks that belong to the parents HYPOTHESIS: Come up with a possible answer to the question

10. QUESTION: How do coot parents know which chicks are brood parasites and which belong to them? HYPOTHESIS: Coot parents use the chicks that hatch first as a reference for recognizing their own offspring. Dr. Dai Shizuka Dr. Bruce Lyon

11. Shizuka & Lyon’s EXPERIMENT: Day 1 2 345 2 345 Host FirstForeign First Compare proportion of host chicks that survive to the proportion of foreign chicks that survive = host chick: related to parents = foreign chick: unrelated to parents

12. Clicker ?: ‘Host First’ condition My graph looks most like:

13. Clicker ?: ‘Foreign First’ condition My graph looks most like:

14. RESULTS: What Shizuka & Lyon found (Clicker ?: A)(Clicker ?: B) Nestlings that belong to the host are more likely to survive than foreign nestlings Foreign nestlings are more likely to survive than nestlings that belong to the host CONCLUSION: Parents can recognize foreign chicks in their nest based on cues learned from their first-hatched chicks.

15. RESULTS: What Shizuka & Lyon found (Clicker ?: A)(Clicker ?: B) Nestlings that belong to the host are more likely to survive than foreign nestlings Foreign nestlings are more likely to survive than nestlings that belong to the host CONCLUSION: Parents can recognize foreign chicks in their nest based on cues learned from their first-hatched chicks.

16. Why is survival < 100% CONCLUSION: Parents can recognize foreign chicks in their nest based on cues learned from their first-hatched chicks.

17. A third experimental group Day 1 2 345 2 345 Day 2 Host FirstForeign FirstMixed = host chick: belongs to parents = foreign chick: does not belong to parents Confirm that parents are using information based on chicks that hatch first

18. Clicker ?: ‘Mixed’ condition My graph looks most like:

19. RESULTS: What Shizuka & Lyon found (Clicker ?: C) CONFIRMATION: Parents cannot recognize their own chicks when information on the first day is unclear

20. RESULTS: What Shizuka & Lyon found (Clicker ?: C) CONFIRMATION: Parents cannot recognize their own chicks when information on the first day is unclear

21. A.The results prove the hypothesis B.The results disprove the hypothesis C.The results support the hypothesis D.The results do not support the hypothesis E.The results are inconclusive HYPOTHESIS: Coot parents use the chicks that hatch first as a reference for recognizing their own offspring. CONCLUSION: Parents can recognize foreign chicks in their nest based on cues learned from their first-hatched chicks.

22. The Scientific Method Observation Question Background Knowledge Hypothesis Experiment: Make Predictions Analyze Results Conclusion

23. What are the costs of raising parasitic offspring?