It sets its stall out quite honestly at the outset, pointing out that the comparisons even though math based are subjective in what they choose to measure, but one thing to remember when looking at the colouring of animals and plants is typified by this point:

> … ultimately loses out in our ranking because it is dark enough to mistake for black in the wrong lighting …

The colouring is not for the benefit of our eyes, and will look quite different in theirs. Most birds have four-colour based colour vision rather than the three-colour system that human eyes use (we both also have “black and white” vision provided at the same time by the rods while the cones deal with specific frequencies for picking out colour), the forth registering in the ultraviolet range, so even in the lighting that confuses out eyes the patterning might be quite striking to other birds.

Plants take advantage of this: things that look relatively featureless to us might have patterning so eyes that have those extra receptors, such as petals that when looked at in a way that translates the UV wavelength into something we can perceive have markings that may help to guide birds and insects in to the pollen at their centres.

Somewhat off-topic, but that page is unreadable. I need to zoom in to 200% to read the charts, but then the normal text is gigantor. It looks like it could be interesting content, but when I need to zoom in and out every time I scroll down, it is just a painful experience to try to read the page.

First bird I thought of and was surprised not to see get a ranking was the rainbow lorikeet, one of the more common birds in suburban Australia.

https://simple.wikipedia.org/wiki/Rainbow_lorikeet#/media/Fi...

I love graphics like this. Very nice aesthetic choices.