How Vertebrates Developed the Ability to See Color

Lampreys possess five photoreceptor types that may provide insights into the origins of color vision in vertebrates.

• The lamprey Geotria australis has five types of photoreceptors with different spectral sensitivities.
• Each photoreceptor type exhibits cone-like structural features.
• Five visual pigment genes are expressed in the lamprey's retina, corresponding to major classes of vertebrate opsin genes.
• The presence of multiple opsin genes suggests their origin occurred early in vertebrate evolution.
• These findings may indicate that the genetic basis for color vision existed before the divergence of jawed and jawless vertebrates.

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