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Related Experiment Video

Updated: Mar 1, 2026

Using a Thermal Camera to Measure Heat Loss Through Bird Feather Coats

Using a Thermal Camera to Measure Heat Loss Through Bird Feather Coats

Published on: June 17, 2020

POPULATION AND DEVELOPMENTAL VARIATION IN THE FEATHER TIP.

Trevor Price¹, Ellen Chi¹, Mark Pavelka¹

¹Department of Biology C-016, University of California at San Diego, La Jolla, CA, 92093, USA.

Evolution; International Journal of Organic Evolution

|June 2, 2017

Summary

This summary is machine-generated.

Developmental processes influence adult variation. This study on warbler feathers reveals early feather parts show high population variation, while later parts exhibit reduced variation due to developmental integration.

Keywords:

Canalized growth developmental abnormalities feather development feather patterns fluctuating asymmetry phenotypic and developmental correlations

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Last Updated: Mar 1, 2026

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Area of Science:

Developmental biology
Evolutionary biology
Ornithology

Background:

Understanding variation in adult traits requires dissecting underlying developmental processes.
Feather development offers a unique model to study developmental history recorded in adult form.

Purpose of the Study:

To document population variation in feather tip development.
To provide a developmentally based explanation for observed variation levels.
To partition variation into developmental components.

Main Methods:

Analysis of feather variation in warbler chicks.
Partitioning population variation into fluctuating asymmetry, among-family, and within-family components.
Examining variation in early versus later formed feather parts.

Main Results:

Early feather parts exhibit high population variation (CV ≈ 30%).
Later feather parts show reduced variation, with lower among-individual and developmental noise components.
High integration among individuals in early and later parts, but lower integration for developmental noise.

Conclusions:

At least two distinct developmental processes influence feather growth and variation.
These processes interact to create relative invariance in later feather parts.
Feather development provides insights into evolutionary constraints on developmental processes.