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Related Experiment Video

Updated: Oct 2, 2025

Experimental Manipulation of Body Size to Estimate Morphological Scaling Relationships in Drosophila

Experimental Manipulation of Body Size to Estimate Morphological Scaling Relationships in Drosophila

Published on: October 1, 2011

Genome size evolution in the diverse insect order Trichoptera.

Jacqueline Heckenhauer^1,2, Paul B Frandsen^1,3,4, John S Sproul^5,6

¹LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Frankfurt 60325, Germany.

|February 26, 2022

Summary

Transposable elements (TEs) drive large genome sizes in caddisflies, impacting gene regions and linking genome expansion to ecological diversity. This study reveals key mechanisms in insect genome evolution.

Keywords:

Trichoptera biodiversity; de novo genome assembly genome duplication genome size evolution genomic diversity genomics insects repetitive elements transposable elements

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Area of Science:

Evolutionary Biology
Genomics
Ecology

Background:

Genome size influences species' form, function, and ecological success.
Two main drivers of eukaryotic genome evolution are polyploidy and repetitive element activity.
Caddisflies (Trichoptera) offer a model system for studying genome size evolution across diverse insect lineages.

Purpose of the Study:

To investigate the drivers of genome size variation in caddisflies.
To understand the role of transposable elements (TEs) in genome evolution.
To explore the relationship between genome size and ecological diversity in insects.

Main Methods:

De novo genome assembly of 17 caddisfly species.
Comparative genomics analysis across major Trichoptera lineages.
Innovative method to examine TEs associated with BUSCO genes.

Main Results:

A ~14-fold variation in genome size was detected across Trichoptera.
Repetitive element expansions, especially TEs, are significant drivers of large caddisfly genomes.
TE expansions impact protein-coding gene regions, showing a linear relationship with genome size and are linked to increased ecological diversity.

Conclusions:

TE activity and TE-gene associations are crucial for understanding genome evolution.
Expanded genomes are preferentially found in ecologically diverse caddisfly clades.
Findings provide a foundation for future research on TE roles in species with high diversity.