Hello Molly.
Why are you so amazed by twins?
I took my 2 to get their eyes tested at the start of the holidays - turns out they each have perfect vision in their right eye and have exactly the same level of short sightedness in their left eyes. No colour blindness though.
Bet you're thrilled that I told you that : )
Twins are fairly rare, severe red green deficiency is also rare, I've only known 2 in many decades. Multiplying the two rarities together gives not much chance of coming across twins with red/ green deficiency unless of course twins are more prone to red/ green deficiency or people with red green deficiency are more likely to have twins.Take it away flobadob...
Some people (virtually all female) have a four receptor colour vision. They can distinguish more shades of green than the ordinary three receptor system. My ex was among these people. I had brown clothes that she always insisted were a shade of green.
I know a guy who is totally colour blind but I have to say his tastes in shades of grey are impeccable.
I never knew that beso, fascinating. Honestly i think I might be like that, with four receptors. Mum and dad just call things brown, but i'm like 'no my shoes are greeny brown almost karki to me!' and it happens with other things.
The vast galactic distances amaze me. The stars we are discovering even now may have blown up millions of years ago.
The ability to clearly distinguish between blue/green is quite common. This deficiency varies from person to person. A person rarely is completely colour-blind.
lime and pink are no problems but dark red and dark green, like our camellia bush, is very hard for me to see from a distance (no problem close up, I don't know why).
I still find it amazing that you can pick up a little piece of plastic, and press buttons on the front.
If you press them in the right order you can speak to someone you know in Australia.
But what i find fascinating and mind boggling is the fact that when i look up at the night sky and see the stars ; what i'm actually seeing is some of the stars as they were years ago - i.e the light has been travelling for years and is only now , just reaching us .
The vastness of the universe is truly mind boggling
To point to where the Sun is in the sky, point two degrees (3.9 times the diametre of the Sun) to the west. This is how far the Sun has moved in the time it took for its light to reach us.
jno, the reason is that the sensivity of the cones that detect red and those that detect green on our retinas overlap at low levels of light. So what you experience is quite common. When that overlap is greater then you get red/green colour-blindness at normal light-levels. I would imagine that red/blue colour-blindness must be rare if not impossible, so far apart are those two colours in the spectrum. But I might be wrong.