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(05-30-2019, 07:56 AM)Rishi Wrote: Why are tigers orange? Prey see them as GREEN, experts say

Colin Fernandez, Daily Mail
28th May 2019

*This image is copyright of its original author

• A computer simulation was run to see how animals viewed the tiger.
• Prey such as the deer are effectively colourblind so view tigers as green.
• This allows them to better camouflage against their natural background.
  

It is a question that has long puzzled scientists - exactly why are tigers orange?
One might think it makes them more conspicuous - particularly against a leafy green forest background.

William Blake summed it up in his famous poem known by generations of schoolchildren: ‘Tyger, tyger, burning bright/ In the forest of the night.’ But now the answer is at hand.
While conspicuous to us, computer simulations of what the big cats look to the main animals they prey on, deer, shows a different picture.

While conspicuous to us, computer simulations of what the big cats look to the main animals they prey on, deer, shows a different picture

WHICH ANIMALS ARE COLOURBLIND? 

The study simulating what colours preys of the tiger see when looking at the predator found that animals like deers are essentially red-green colour blind like some humans.
This means they only pick up greens and blues and not oranges and reds.
This means they are more sensitive to the blue-green portion of the spectrum (due to their eyes' high rod density) and less sensitive to light of long wavelengths (orange and red).
Therefore the tiger appears green to deers rather than orange, which helps their camouflaging effect.
Other animals that are red-green 'colourblind' include: wolves, coyotes, foxes, bulls, dogs and cats
Humans with normal colour vision, can see red, blue and green colours.
But deer can only pick up blue and green light, they are effectively colourblind to the colour red, like some humans.
It means the tigers’ orange colouration look green to them, allowing them to blend perfectly into the background, new research claims.
Dr John Fennell at the University of Bristol and colleagues said that they used computers to estimate how detectable a given animal was.
They did this by using images of the environment in which the animal lives, and then generating images to see whether the camouflage helps the animal to blend in.
Dr Fennell writes that by simulating what the world looks like to animals who are ‘dichromats’ - who cannot detect the difference between red and green - ‘we also identify the optimum colours for concealment and visibility’.

Now it makes sense, because a tiger hiding in a green jungle is not the same as a lion hiding in yellow or light brown vegetation: 

Bangladeshi Sundarban tigers' number rises in 3 years (news in itself): https://www.thedailystar.net/frontpage/b...rs-1746550

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Masai lion hiding in grass: https://www.allposters.com/-sp/Lion-Pant...33503_.htm 

*This image is copyright of its original author

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