Grasshopper Color Vision

Grasshopper

Grasshopper

Humans and insects typically perceive color through 3 types of photoreceptors present in the retina of the eye. In humans, each photoreceptor type is maximally sesitive to a different wavelength of light in the red, green and blue portions of the spectrum. The brain integrates signals from the 3 receptors types and produces the sensation of color. Many insects use a similar process but with the wavelength of light sensed shifted to detect green, blue and ultraviolet. The grasshopper, Phlaeoba, can discriminate between between red and green and other colors, even though the eye has only one type of photoreceptor pigment. How does Phlaeoba discriminate color?

The compound eyes of Phlaeoba have some ommatidia that are clear and others that contain a screening pigment. The screening pigment filters some wavelengths of light more than others. Receptors without the pigment are maximally sensitive to light at 525 nm wavelength.  Those receptors with screening pigment are maximally sensitive to light at 545 nm wavelength. Thus, a single photoreceptor pigment can function as if it were 2 distinct pigments with different sensitivities and enable the grasshopper to discriminate color.

About jjneal

Jonathan Neal is an Associate Professor of Entomology at Purdue University and author of the textbook, Living With Insects (2010). This blog is a forum to communicate about the intersection of insects with people and policy. This is a personal blog. The opinions and materials posted here are those of the author and are in no way connected with those of my employer.
This entry was posted in Biomaterials, by jjneal, Vision. Bookmark the permalink.

One Response to Grasshopper Color Vision

  1. Pingback: Grasshopper Color Vision | Entomo Planet

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s