Seeing beyond VIBGYOR [archives]

[This piece was originally hosted on my now-defunct MA course blog.]

Ah, the human species. For all our coolness, we can’t do what a little mantis shrimp can – see beyond the VIBGYOR spectrum of light. The mantis shrimp has what scientists call hyperspectral colour vision, something that ESA’s ExoMars rover’s camera eyes will have. Essentially, hyperspectral imaging allows a camera to view not just the visible-to-humans spectrum but also the infrared and ultraviolet bands.

Check out a simulation of the ExoMars rover, designed to drill into the Martian surface in search of subterranean life.

So, why exactly have I started talking about funky shrimps and Mars rovers? Well, this morning, we had a lecture by Lewis Dartnell who is an astrobiologist. [Cue: “Oooh!”] During the break, Dr Dartnell, who is working on some aspects of the ExoMars rover, mentioned the hyperspectral imaging camera and set my mind thinking.

I began to think of what it might mean if we were able to see light on either side of the VIBGYOR spectrum.

For starters, human history might have taken a very different route. Think of the importance of night vision in modern urban warfare – the goggles detect infrared (IR) light emitted by enemy combatants. Remember the scene from Predator where the alien kills the humans by detecting their body’s infrared radiation? Now, imagine how the various ambushes planned by the various warriors of antiquity might have panned out if all the people could detect their opponents by their body heat!

Warriors could also use their ultraviolet (UV) vision to spot blood and use it to track down their enemies. This, of course, is under the assumption that the same mechanism that would allow us to see UV radiation doesn’t cause us to go blind from over-exposure to Sol’s UV light. Of course, since the insects and birds survive fine, I don’t see a reason to assume that it would do us physical harm.

Think, also, of the lack of privacy and the social structure in which the humans would have evolved. Rudimentary huts wouldn’t have been adequate to hide lovers from the eyes of their families, equipped with IR vision! Would we, as some primates do, have indulged in public displays of more than just affection? I believe clothes would only be worn to protect oneself from the elements, and not to protect one’s modesty, whatever that term might mean in a society capable of infrared vision. Human history and sociology might have been very different, only if we saw differently.

Wikipedia informs me (as do another couple of sources) that many insects are aided in their flight navigation by the ultraviolet radiation from celestial bodies. I’m not sure about the veracity of these claims, but assuming they were true, I imagine that the way in which we went about exploring this planet of ours might have been rather interesting.

Another thought that occurred to me involved the nature of art. I imagine that with a larger palette of colours at our disposal, artists would have found unique methods of expressing themselves. I’m not sure I can imagine what this might have been like, but the possibility for art, photography and filming seems very fascinating.

“But what about the downsides?” I hear you ask. Surely there are a few. I think the one that hits me squarely between the eyes involves our perception of hygiene. Human urine, like the urine of cats, dogs and rodents, glows in ultraviolet light. My first thought was something along the lines of, “Eew!” Eloquent, yes. The thought of being able to see the glow of urine isn’t a pleasant one, and I was tempted to classify it as a downside.

Then a thought struck me.

Our ancestors might not have had the plague, since rat urine might have told them where the mice lived and bred. Who knows what the population of the world would have comprised of?

In addition, we have evolved socially to consider the act of urinating a private one (albeit shared with hundreds of people of the same sex, over the course of our lives). We consider it disgusting to urinate anywhere other than a toilet. We might call the perpetrator uncultured. This, of course, is the “we” that has evolved in the absence of UV vision. If the progenitors could see urine glowing, I think our social dynamic might have been slightly different. Thinking of all the animals that mark their territory with their fluids, I think one of two things might’ve occured:

  1. We would still live in what we define as a cultured society, but without the pets we keep – no cats and no dogs.
  2. We would turn into one of those species that marked our territories with urine. Landscaping would’ve have looked SO weird.

Anyway, I’m not sure what all the consequences would be if we were able naturally to see a range of colours beyond VIBGYOR, but at least we now have the technology to explore these spectra.