ELi5: How do scientists interpret what some animals see



You get taught that animals see different colors. I was reading a book about animal senses and I thought how do we know what some animals see?

In: Biology


When we dissect their eyes, we see similarities to our own eyes. We have structures called rods that are sensitive to low-light and peripheral vision and cones that are sensitive to colors. Humans have 3 cones (Red, Green, and Blue light sensitivity). Dogs have 2 cones. Blue and Yellow light sensitivities. So they don’t see reds and the greens are yellow-y, not having a specific green cone.

How do they know though, that a cat can see so many times better than humans in low-light conditions?

Truth is we don’t actually know for sure, we don’t even know if every human experiences sight and colour the same way.

However we can infer based on what we know about eyes from human and animal dissections is that some animals lack cells in the eye we posses. We then infer that due to animals not having the same sets of colour receptors as we do that they see colour differently.