How do we know that animals are colour blind?

Question

The theory with the bull is that it's not the colour of the waving flag, it's the waving of the flag itself that annoys him, the jiggly motion...

with the goldfish, they put a mirror to split the tank in half. They watched the fish try to swim into the mirror, then they measured how long it took for the fish to try to do it again.

Answer 1

Not all animals are colour-blind by any means.

Many mammals, such as dogs and cats, only have two sorts of "cones" in their retinas (the bit at the back of the eye that actually recognises the light). This usually means that they cannot distinguish between red and green.

Humans share with many other primates (apes and monkeys) the ability to distinguish three separate colours - red, green, blue - because we have three different sorts of cones.

However, some tropical birds have *four* sorts of cones - so they actually see *more* colours than we do.

Answer 2

Inside the eyeball are two types of receptors-rods and cones.
Rods allow the animal to see in dim light.
Cones allow color vision. There are three types of cones.

Not all animals are color blind.

People have all three types of cones.
Dogs have two types of cones. This is how we know that dogs can see like a person with red-green colorblindness.
Horses also have two types of cones, but not the same two that dogs have. This is why horses can see the colors green and yellow best.

EDIT: And actually those bulls don't see the color red. It is the movement of the cape that the matador waves around that makes them charge. The reason they use red capes is just because of cultural and traditional reasons.

Answer 3

Scientists can dissect the eyes of different organisms. Within the eye, they can view the volume of special "vision" cells called Cone cells and Rod cells. Some are responsible for color vision, and some are responsible for light/dark contrast vision. Depending on the number, that is a good indicator as to whether or not that animal can see colors.

Answer 4

They took a whole group of animals, including domestic dogs (Canis familaris), cats (Felis catus), and even wild animals such as deer (Odocoileus virginiana), and African elephants (Loxodonta africana) and put them into a very large room.

An instructor stood at the front of the room, and held up a giant blue card and yelled out "What colour is this card?"

Not one single one of the animals got the answer right, and thus we know that animals are colour blind.

Answer 5

I know what you mean.
Its the same as How do they know that a goldfish only has a memory of 2 minutes. What did they do to find that out

Answer 6

they have taken the eyes of dead dogs or cats, and have cut the lense off the eye and have done tests to prove that they only see black and white

Answer 7

are they!? how come the Spanish bull recognise the red colour then!

Answer 8

i dont know but good q!! have a star!