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VOLUME 15 TEACHING ISSUES AND EXPERIMENTS IN ECOLOGY
PRACTICE

Quantifying the impact of a brood parasite on crows

Great spotted cuckoo Clamator glandarius chick (right) with crow Corvus corone nestlings. Photo © Vittorio Baglione. Used with permission.

AUTHOR

Clare Trinder

School of Biological Sciences, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen, AB24 3UL, Scotland

(c.j.trinder@abdn.ac.uk)


THE ECOLOGICAL QUESTION

What is the nature of the impact of a brood parasite on its host and how much effect do brood parasites have?

ECOLOGICAL CONTENT

Parasitism, mutualism, shifting nature of interactions

WHAT STUDENTS DO

This class was designed for an introductory ecology course. Students are introduced to Microsoft Excel PivotTables by amending an existing PivotTable, then create their own PivotTables to explore the main data sets. These data sets provide information on the breeding success of carrion crows parasitised by great spotted cuckoos in Spain. Students summarise the large data sets, produce bar charts, calculate standard errors and add error bars to their plots. As they work through the exercises, students are asked to summarise the results they have obtained and to think about what this means ecologically. Finally, they use the whole set of results to understand the nature of the interaction between cuckoos and crows in this area.

SKILLS

  • Application of existing knowledge on parasitism and mutualisms
  • Analysis of data using Excel PivotTables
  • Interpretation of data to evaluate the nature of species interactions

STUDENT-ACTIVE APPROACHES

Guided inquiry, peer feedback, small group discussion, problem-based learning

ASSESSABLE OUTCOMES

  • Generation of a set of PivotTables and bar graphs to summarise two large data sets
  • Answers to a set of questions to demonstrate understanding of the interaction between great spotted cuckoos and crows in Spain
  • After the data analysis is complete, students can be directed to the paper (Canestrari et al. 2014) and asked more detailed questions based on the findings

SOURCES

Data from Canestrari et al. 2014. From parasitism to mutualism: unexpected interactions between a cuckoo and its host. Science, 343: 1350-1352.

Supplementary materials available from: www.sciencemag.org/content/343/6177/1350/suppl/DC1

Data available from: DRYAD (DOI:10.5061/dryad.j81r0)

DOWNLOADS

Description of Resource Files:

ACKNOWLEDGMENTS

I am grateful to Daniela Canestrari for kindly granting permission to use this data set and to Vittorio Baglione for providing the photo. The students in BI2020 Ecology in 2018 and 2019 generously engaged in this exercise and provided helpful feedback as I fine-tuned the activity. The teaching assistants who helped these classes run have also been invaluable. Two anonymous referees and Kathy Winnett-Murray provided helpful comments on the manuscript.

CITATION

Clare Trinder. April 2019, posting date. Quantifying the impact of a brood parasite on crows. Teaching Issues and Experiments in Ecology, Vol. 15: Practice #2 [online]. http://tiee.esa.org/vol/v15/issues/data_sets/trinder/abstract.html