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Testing the relationship between human occupancy in the landscape and tadpole developmental stress
Paula C Eterovick1, Luís F F Bar1, Jorge B Souza2
1Programa de Pós Graduação em Zoologia de Vertebrados, Pontifícia Universidade Católica de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Plos One
|March 21, 2015
Summary
Researchers investigated fluctuating asymmetry (FA) in tadpoles to detect amphibian stress from human habitat changes in Brazil. However, the study found no direct link between landscape alteration and FA levels in the endemic Bokermannohyla saxicola.
Area of Science:
- Ecology
- Environmental Science
- Conservation Biology
Background:
- Amphibian populations face global declines, primarily driven by human activities like habitat fragmentation.
- Brazil, a biodiversity hotspot for amphibians, experiences significant habitat destruction, yet documented declines are scarce.
- Developing sensitive methods to detect amphibian stress before population collapse is crucial.
Purpose of the Study:
- To assess the utility of fluctuating asymmetry (FA) in amphibian larvae as an indicator of anthropogenic stress.
- To investigate the relationship between human landscape modification and FA levels in tadpoles of Bokermannohyla saxicola.
- To explore potential factors influencing the detectability of environmental stress through FA measurements.
Main Methods:
- Field study conducted in the Espinhaço mountain range, Brazil, focusing on endemic Bokermannohyla saxicola tadpoles.
- Measurement of fluctuating asymmetry (FA) using tadpole denticle rows and eye-nostril distance.
- Quantification of human-altered habitat cover in the landscape surrounding tadpole sampling sites.
Main Results:
- Fluctuating asymmetry (FA) levels varied significantly among different sampling localities.
- No statistically significant relationship was found between the degree of landscape human modification and tadpole FA levels.
- The chosen traits for FA measurement may not be sensitive indicators of landscape-scale anthropogenic stress in this species.
Conclusions:
- Fluctuating asymmetry (FA) in the studied traits of Bokermannohyla saxicola tadpoles did not correlate with landscape human modification.
- Observed FA variations might be influenced by unmeasured local environmental factors or genetic differentiation among populations.
- Further research is needed to refine FA as a reliable biomarker for amphibian stress in human-altered landscapes.
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