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Updated: Jun 19, 2026
08:14
Ecotoxicological Methodologies to Evaluate Biomarkers at Different Scales in Neotropical Anurans
Published on: April 28, 2023
Variations in Sexual Size Dimorphism in Two Anurans Along an Urbanization Gradient in Shanghai: Assessment of
Ben Li1, Ningning Liu2,3, Shurong Zhong2
1College of Life Sciences, Zhejiang Normal University Jinhua China.
Ecology and Evolution
|June 18, 2026
Summary
Urbanization impacts frog sexual size dimorphism (SSD). Urban populations of Fejervarya multistriata and Pelophylax plancyi showed altered SSD, supporting the inverse of Rensch's rule. This highlights species-specific responses to urban environments.
Area of Science:
- Ecology
- Evolutionary Biology
- Herpetology
Background:
- Sexual size dimorphism (SSD) influences animal ecology and evolution.
- Urbanization is a growing factor affecting wildlife morphology, yet its impact on anuran SSD is understudied.
Purpose of the Study:
- To investigate how urbanization affects SSD in two frog species: Fejervarya multistriata and Pelophylax plancyi.
- To determine if observed SSD variations align with Rensch's rule or its inverse.
Main Methods:
- Comparing SSD across urban, suburban, and rural gradients in Shanghai.
- Analyzing snout-vent length (SVL), head width, and limb lengths.
- Applying reduced major axis regression to test Rensch's rule.
Main Results:
- Fejervarya multistriata showed higher SVL and SSD in urban areas.
- Pelophylax plancyi males exhibited higher SVL in urban areas.
- Both species' SSD supported the inverse of Rensch's rule.
- Size scaling rates were higher in urban/suburban populations.
Conclusions:
- Urbanization significantly shapes anuran SSD, following the inverse of Rensch's rule.
- Species exhibit differential responses to urbanization, with F. multistriata being urban-sensitive and P. plancyi being urban-associated.
- Morphological variations and size scaling rates differ between these species under urbanization.
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