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The Dilution Effect

How Biodiversity Can Affect Human Health


Author(s)

Claudia Stein
Department of Biology and Tyson Research Center
Washington University in St. Louis
cstein@wustl.edu
Eleanor A. Pardini
Environmental Studies
Washington University in St. Louis
epardini@wustl.edu

Abstract

In this case study students are provided with information for piecing together the story of how forest fragmentation and biodiversity loss can affect the risk of Lyme disease transmission to humans. The case introduces the dilution effect, a widely accepted theory—and one of the most important ideas in disease ecology—which suggests that disease risk for humans decreases as the diversity of species in an area increases. It also explains how landscape fragmentation, one of the most common threats to biodiversity, can influence the risk of Lyme disease for humans. Students interpret and discuss various figures to develop a concept map that connects all the individual results of the story. Students gain an appreciation for the complexity of species interactions in an ecosystem, the effects of forest fragmentation on these interactions and the possible consequences for human health. This activity was developed for an undergraduate introduction to environmental sciences course under the topic of biodiversity and conservation, but would also be suitable for interdisciplinary studies interested in examining the connections between conservation and public health.


Objectives

  • Read and interpret scientific graphs.
  • Work productively and collaboratively in a team.
  • Use research results to develop a model of how the loss of biodiversity might influence human health.

Keywords

dilution effect; forest fragmentation; landscape fragmentation; Lyme disease; tick; biodiversity; human health; conservation

Topical Areas

N/A

Educational Level

Undergraduate lower division, Undergraduate upper division

Format

PDF

Type / Methods

Discussion, Jig-Saw, Student Presentations

Language

English

Subject Headings

Ecology  |   Environmental Science  |   Public Health  |   Wildlife Management  |  


Date Posted

8/15/2016

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