I love camouflage and I'd like to share the following picture of an example of very effective camouflage. Look at the first of the two attached files and see if you can spot the bug. Then check the second to see if you got it right.

Tags: camouflage, evolution, nature

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Yes, camouflage is a fine example demonstrating how the processes of evolution have worked well for the good of this species. Did you take the photograph? Where? When? Do you know what kind of insect it was?
Yes, I took the picture of this grasshopper yesterday (27/09/08) at about 3:30pm MT at the mud buttes south of the village of Monitor, Alberta (http://www.trailofthebuffalo.com/index.php?option=com_content&t...) @ about 51 degrees 54'36.10" N, 110 degrees 33'47.20" W. The colours of this grasshopper is less common in my area, with green and brown combinations being more common. When I've spotted grasshoppers like this in my area, they are fairly noticeable, but at the mud buttes they seem to disappear into the landscape, as you can see.
I decided to do a test to see roughly how quickly people could spot the camouflage.

The results are quiet interesting, even if they are not properly scientific, which I note from the outset, this was just just a quick survey.

http://www.bbc.co.uk/dna/h2g2/plain/F19585?thread=6168451
Interesting, but I don't think some of the people who replied realized that they needed to zoom back to see the whole picture. A proper surrey would be interesting, but I think it would have to be done in person rather than on the net, as different monitors would probably effect the results.
And please feel free to pass my picture on.
I could see it and guessed it right first time. But I'm colourblind and have often wondered if there's an impact on the effectiveness of camouflage to be able to blend into natural surroundings when I am seeing it in contrast to it's surroundings in a limited spectrum.
Actually, I thought that most animals are color blind (define that as you will, I'm not in the sciences) - and that it's their grey-vision that makes a lot of camouflage effective. Spotted animals hiding n the savanna grass and that sort of thing....

Gregg
The genetic divergence of trichromatic colour vision dichromatic colour vision is dealt with very effectively in Rendevous 6 of The Ancestor's Tale by Richard Dawkins.

Mammals on the whole tend to have poor dichromatic vision, apes including humans are descended from an ancestral lineage that developed trichromatic vision and kept it.

Genetically I am a trichromat but one of my genes is switched off rendering my vision anomalously dichromatic.

This certainly means that my colour vision is less sensitive since my eyes do not render to my colour vision, colours which are distinct (red can look like black or slate, purple like blue, pink grey and certain greens are entirely interchangeable etc) However on the upside I tend to do better in low-light situations (obviously all eyes need light to see so I can't function in pitch blackness but low light I'm not much troubled by).

I wonder if for camouflage systems which have evolved in a world of trichromatic predation (which is common amongst fish and reptiles for example) if my anomalous dichromacy lends itself to not seeing the complex colour matching - my colours being blander and less diffuse - so making the camouflage is less effective.

I've no idea if that is true or not, I can only report I saw the creature first time and while similar to it's background I can clearly make out it's outline.
I have fairly good colour discrimination, and have always found it fairly easy to find differences in slight colour differences. When taking a picture of this little bugger, I found that I had to keep looking up from the view finder to make sure it was still there, and take several frames to make sure I caught it. Hell, I only noticed it because it moved! An ex-girlfriend of mine once took a picture of me in a black t-shirt and suburban camo pants (the blue type), in front of some shrubs, with black and white film, and it looked as if my legs were gone from my waist to my boots. In colour, the pants stood out quite distinctively, so I wonder how a colour blind person, like your self, would see that in person, and in the B&W photo. My father is colour blind, and always had difficulty in co-ordinating the colour of his clothes, and yet he was an electrician, and was able to sort through thick bundles of multi coloured wires to make sure they were wired correctly. I know he made a few special testing devices to help with this, but I still amazes me at how well he was able to do it.
Regarding electrical work, I was working in an Oxford physics laboratory in the 1960s when a minor apparatus of a colleague 'blew up'. In those days, the RED wire was live, GREEN was earth, and BLACK was the other current carrier. He had interpreted the BLACK as being the earth wire.
I asked how this came about and he said that he was red-green colour blind, and had supposed the two colours that looked the same to him (red and green, in which both seemed to be grey) were the same colour and carried the current, and that the third--the different one--was the earth wire.
Since those we have brown, black and green.
Well since the cameo pants were blue, I think I'd see those fairly well.

Colour in light has three primaries, which unlike pigments are red, green and blue.
I am missing the red channel input, but retain my green and blue channels. To give an analogous example,it's a bit like mixing up several really delicious recipes but leaving out one ingredient common to all. You can still mix the food and it'll taste all right but a bit bland and similar. That's kind of how my colour vision works: everything is bit blander, which is to say the colours are less distinguishable. so I look at fields of lavender and think it's a blue colour - because the red element of the colour is literally missing, leaving only the blue.
The lavender is still whatever colour lavender is but I just cannot decode the red frequencies of light that are reflected so they are left out.

Some people do have monochromatic vision, (black and white, shades of grey) and then they might experience the kind of camouflage effect you describe in the photo. I suspect I would cope okay with that because it's blue contrasting with green. I have difficulty playing snooker. The red, green and brown balls on the green felt are indistinguishable from one and other. Since you have to pot a red ball before a coloured ball which proceed in a particular sequence, I tend to rack up a lot of penalties.

If you father is colour-blind, I'll hypothesise and say your mother is not.
Colour blindness is a trait carried on the X chromosome and is recessive. This means women (who have two x chromosomes) need the colour blindness gene on both in order for it to be expressed. Men who have only one x and one y chromosome can inherit the recessive gene from their mothers and have it expressed in their genome. So your paternal grandmother transmitted the gene to your father where it was expressed, however since your share of his DNA is on your Y chromosome you have not inherited the colour blindness gene from him. Your mother, if she had have carried the recessive gene, may not have been colour blind herself (since she has a redundancy in her second X chromosome ) but it's unlikely she did since in the recombination of the X chromosome in your genome you have not been diagnosed colour blind (and there would be no chance for the gene to be recessive) ergo you don't carry the gene and it won't be transmitted to your children by you.

As for jobs - there are some professions that do forbid colour blind people from working. I recently looked up a job in forensics and one of the essential criteria was MUST NOT BE COLOUR BLIND!

The last time I looked inside a plug, the wires were patterned to get round the problem of colour blindness so I can well imagine that your father could indeed cope.

Was your father red-green colour blind like me (Protanopia) or one of the other rarer kinds that affect the other possible primary colour channels?

My wardobe incidentally is composed (I realised) of mostly blues, greens, blacks, whites and greys. i.e the colours and shades I see most readily. Very few reds or yellows or warmer colours. When it comes to arranging colours I'm pretty good now at guessing what a colour is and also notice when something I'm looking at has one of those bland indistinguishable shades to it ('Is that black or red?' I can hear myself asking...) but it's important to emphasise the role of guesswork I'm not seeing anything other than what I see normally but experience has taught me when I'm not seeing the same thing s everyone else and to also be a pretty good estimator of what the colour ought to be. Just don't ask me to name it!!
My father got into electronics in the last years of WW2, when he got a medical discharged from the RAF(his bomber was shot down in 1941). After the war, dad and a friend opened up an electronics shop in Cardiff, where they made a killing converting old radar sets into single channel TV's. In 1948, he came to Canada while on his way to Australia, met my mother, and stayed. His first job in Canada was on a General Electric cooking show, but then he worked on military contracts, like building the DEW line radar system in the Canadian arctic, As well, He did designing, and installing, of fire control systems, and the like, in various mines, factories and power plants. Before retiring in the mid 1980's, he was the superintendent of the electrical company that installed the electrical controls for Calgary, Alberta's rapid transit system. The wires my dad had to sort out were not simple three, four or seven wire systems. They tended to be more like 25 to 100 + systems, with multiple colour coding. Sorting such wires out can be difficult for a non colour blind person (I know I always had trouble with it)!
As for fuck ups, I remember when I was little, my dad would get me to disassemble old TVs and radios for parts, and getting zapped by the tube capacitors because of my father telling me to short out the wrong colour of wire!
I don't think I'd be that brave! I label all my colouring pens and have them independently verified by someone I can trust not to take the piss.

'What colour is this? will be in my obituary.'

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