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Parasite-mediated competition in Anolis lizards
1Department of Zoology, University of Vermont, 05405, Burlington, VT, USA.
Oecologia
|March 18, 2017
Summary
Malaria infection in Anolis gingivinus lizards on St. Maarten dictates the presence of competing Anolis wattsi. This parasite-mediated competition explains lizard distribution patterns on Caribbean islands.
Area of Science:
- Ecology
- Parasitology
- Herpetology
Background:
- Two Anolis lizard species on St. Maarten are similar in size and highly competitive.
- Anolis wattsi is restricted to central hills, while Anolis gingivinus is widespread.
- Plasmodium azurophilum malaria rarely infects A. wattsi but commonly infects A. gingivinus.
Purpose of the Study:
- To investigate the role of malaria in mediating competition and distribution of Anolis lizards on St. Maarten.
- To understand parasite-mediated competition dynamics in Anolis lizard communities.
Main Methods:
- Observational study correlating malaria presence/absence with Anolis species distribution.
- Analysis of Anolis gingivinus blood to assess pathology caused by Plasmodium azurophilum.
Main Results:
- Anolis wattsi presence is consistently linked to areas where A. gingivinus is infected with malaria.
- Areas without malaria are exclusively inhabited by A. gingivinus.
- Malaria infection in A. gingivinus causes significant blood pathology, including changes in red and white blood cells.
Conclusions:
- Plasmodium azurophilum malaria is a key factor mediating competition between Anolis gingivinus and Anolis wattsi.
- Parasite-mediated competition influences the distribution patterns of these Anolis lizard species on St. Maarten.
- Variable susceptibility to parasitic infection can drive community ecology, suggesting parasite-mediated competition may be widespread in Anolis populations.
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