the excel spreadsheet to obtain estimates of some of the other food web metrics. Consult with a peer and your instructor for feedback. 1. Methods for calculating food web metrics using the excel data set. Food web metric Procedure for calculating with excel data set. How to test for differences due to including parasites. Degree Sort the Quick Pond Links excel spread sheet and identify the entries corresponding to the species ID number. Count the interactions with other species. Use the metadata table to determine which species are parasites. Count the number of links with parasites and those without and compare. Number of taxa (S) Numbers of links (Lo) Link density (d) Connectance (C) %
Answer: Quick Table 2A represents descriptive metadata. You can tell because the title for the table and the final column “column description” both indicate that the information it contains are used to describe or identify the components of the other datasets. Answers for the final part of the question can vary, but should include that having this information can allow the user to better understand how to access and use the dataset as well as relate it back to the biological characteristics of the organisms and the community being described. Activity 5: Choose 3 characteristics from the “Quick Pond Nodes” data set for each of your taxa and explain what they mean using Quick Table 2A. Answers will vary depending on the taxa and the characteristics chosen, but should be reported accurately and completely. Activity 6: Locate your chosen taxa in both the “ConsumerSpeciesID” and “ResourceSpeciesID” columns. It may be helpful to use the “sort” and “filter” functions in excel as illustrated in the example above. How many resource items does each taxon have? How many consumers? List the SpeciesID number and identify up to ten taxa that are interacting with one of your focal taxa using the Quick Pond Nodes and metadata tables. Answer: Please see excel file for the number of resources and consumers for each taxa. This file can also be used to check the species identification for the SpeciesID number in the student response. Activity 7: Are any of the taxa you investigated parasites? If so, how do they interact with free-living species? If you have investigated free-living species, did you observe any interactions with parasites? If so, what were they? Share your thoughts with another student or group and compare their responses. Answer: Answers will vary depending on the students’ taxa. Potential answers for the parasites include using particular free-living taxa as hosts in their life cycle or that the parasite can also serve as prey for a free-living species. Likewise, students could indicate that a free-living species was infected by or consumed a particular parasite at one or more stages of its life cycle. Activity 8: Draw a simple food web module including your focal taxon from the final part of Activity 6 and all its consumer and resource interactions. Answer: Answers will vary depending on the student’s taxa. Like the example provided above for Helisoma sp. snails, a complete and accurate answer will have the number of arrows equal to the number of interactions where the focal