Hymenoptera eye color

Do bees and wasps actually have different eye colors or is it a quirk of human eyes/brains/technology? If they do, what affects the color? Can it vary within a species? Thanks for any answers!

With more than 120K species of hymenoptera, it would be amazing and bizarre if there wasn’t eye color variation among species. And with species constantly undergoing not only natural selection, but also mutations, genetic drift, etc. it would be astonishing if there wasn’t also intra-speciic variation in this trait in at least some of those species. One of my favorite examples of eye colors in insects are in the Tabanidae, the horse and deer flies. Hard to get a good photo of them, but look for example at this: https://www.inaturalist.org/observations/52091077 and https://www.inaturalist.org/observations/125868570

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Is there something in their eye structure that shines green? This is a bit different, because they appear reflective (and often stripey), while some bees seem to have a solid color https://www.inaturalist.org/observations/92306720

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I would guess that it is iridescent, but not actually luminescent (it does not emit light in the dark, just changes light from one wavelength to another). Just like a purple feather doesn’t have purple pigment, and a blue human eye doesn’t have blue pigment, a green fly-eye many not have green pigment. But I think it is fair to say that things that get their colors from structures rather than pigments are still truly that color. https://en.wikipedia.org/wiki/Structural_coloration

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Related question: what is the function of the patterning of eye coloration for example on Megachilidae

https://www.inaturalist.org/observations/124475529

or Ceratina

https://www.inaturalist.org/observations/123933513

–the arrangement of dark, elongated ovals? These aren’t the most striking examples, but I find them captivating–

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Commentary, not an answer: here is a great observation from @amoorehouse showing how eye color can differ even interspecifically: https://www.inaturalist.org/observations/80408009

One of the many reasons I love looking at insect observations on iNat is to see the eye color, as this is often lost in the dead specimens that I spend most of my time looking at.

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Male and female bees often have different eye colour, but it’s just one for each sex, I have never seen different eye color between specimens that wasn’t linked to sexual dimorphism.

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Great example! The two groups I’ve really noticed eye colors in are Apinae and Crabronidae.

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There are two types of color, pigment color and structural color. To the observer (us, for example) the color of something is what wavelength of light is entering our eye from the object. Pigment color is due to a substance which is absorbing certain wavelengths of light–so we see the wavelengths not being absorbed. Structural color is due to the geometry of microscopic colors reflecting certain wavelengths of light in certain directions (thus we only see certain wavelenghts). Bees and wasps definitely have different eye colors (if you see different colors, then it’s real). And the colors are, I think, most certainly due to a combination of pigment and structural color. I found a really interesting review paper on insect eye color here.

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I was actually going to make a thread on insect eye color myself and then my internet started giving me trouble so I’m happy to see this thread here! I’m glad I’m not the only one interested in this. I recently found my first deer fly and was amazed at the colors of its eyes. Do insects gain anything from patterns like this on their eyes? If these color differences can be due to structural differences in certain parts of their eyes, how does that affect their vision?

YES! And everyone has their own perception of color, as well as how many colors they perceive.

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