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Updated: Mar 1, 2026
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Determination of Photoreceptor Cell Spectral Sensitivity in an Insect Model from In Vivo Intracellular Recordings
Published on: February 26, 2016
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How exaptations facilitated photosensory evolution: Seeing the light by accident
Gregory S Gavelis1,2, Patrick J Keeling2, Brian S Leander2
1School of Life Sciences, Arizona State University, Phoenix, AZ, USA.
Summary
Exaptation drives photoreception evolution by repurposing genes for new functions, especially in protists. This process, involving gene transfer and endosymbiosis, highlights evolutionary creativity in developing vision.
Area of Science:
- Evolutionary Biology
- Molecular Biology
- Cell Biology
Background:
- Exaptations are adaptations with a changed function.
- Exaptation facilitated major photosensory innovations like lenses and photopigments.
- Understanding exaptation's role in photoreception is crucial for evolutionary studies.
Purpose of the Study:
- To review findings on how exaptation shaped photoreception across life.
- To emphasize the role of exaptation in unicellular eukaryotes (protists).
- To illustrate the origins of photoreception through evolutionary novelty.
Main Methods:
- Review of new and neglected findings on exaptation and photoreception.
- Phylogenetic analysis of protist photoreception origins.
- Examination of gene and organelle recruitment via lateral gene transfer and endosymbiosis.
Main Results:
- Multiple independent origins of photoreception are evident in protist phylogeny.
- Protists utilize diverse genetic and organellar ingredients for photoreceptors and eyespots.
- Exaptation, alongside natural selection, explains the emergence of novel photoreceptive structures.
Conclusions:
- Exaptation is a key mechanism for the evolution of photoreception.
- Protists showcase extreme evolutionary creativity in developing vision through exaptation.
- Exaptation provides insights into the fundamental origins of sensory systems.
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