Tuesday, June 16, 2020

Compared to Hummingbirds, We're Colorblind

Birds can perceive colors in parts of the electromagnetic spectrum beyond what we humans can see. 

Costa Rican hummingbird, from Ask a Biologist

Humans have only three color receptors, but birds are tetrachromats, with four color receptors. In addition to birds, many reptiles, fish, insects, spiders, shrimp, and other invertebrates can see colors beyond our range of awareness. The scientists estimate that as much as 35 percent of the color experience of birds includes colors we can't even imagine, not just additional colors, but combinations of colors such as ultraviolet plus green. 

Some birds that look plain to our eyes have patterns that can only be revealed by translating those extraspectral colors into visible light. According to NatGeo:
"This extra level of discernment might also have been a trait of dinosaurs, which are thought to have sported colorful feathers. Mammals evolved as nocturnal beings that did not need to see the rich hues of the daylight world, so most—like your pet dog and cat—are dichromatic, and have only blue and green cones. People evolved a third cone (red), possibly because early primates developed an appetite for ripening fruits."
More online resources
Science Friday Podcast: A Bird's Eye View of Color


Bob said...

Perhaps dinosaurs really had the sort of vision illustrated on page 103 of your book Dinotopia: A Land Apart From Time!

Steve Gilzow said...

Wish I could remember the source...William James? Alan Watts? There is a quotation about our five human senses acting as much as constrictor valves as receptors. It’s good to recognize how subjective and limited our reading of reality is.

Susan Krzywicki said...

This, along with the news that the universe is flat, has boggled my mind.

Diane said...

Another reason to be jealous of hummingbirds!

Diane said...

Another reason to be jealous of hummingbirds!

Aaron said...

Tetrachromy occurs in humans too. It's just not the default and the range is different. We have 2 different red cones. Only women get it because genes for cones are carried on the x chromosomes. Sometimes someone inherits both of the reds. There is one woman who has been confirmed with it who is also an artist, giving her the knowledge and vocabulary needed to describe her experience.

Concetta Antico ~ Tetrachromat & Fine Artist

James Gurney said...

Aaron, I've heard of human tetrachromats, but I suppose even if they're artists they won't know what others don't see unless the comparison of awareness comes to their attention.

Steve, it make sense that Watts would have covered this. I remember he often spoke of how our senses filter out as much as they take in. He also talks about how our experience of the world IS our sensory appreciation of it, so whatever warping or constriction happens affects our lived experience of the world.