Birds see a completely different world from what we know, and now, thanks to a specially designed camera that simulates Birdo vision, we can get an indication of what that looks like.
The images are not only fascinating, they also explain why birds can navigate through dense foliage so precisely.
Behavioral biologist Cynthia Tedore, formerly from Lund University in Sweden, explains that the team wanted to look for patterns in nature that birds see, but scientists have not thought to search.
They opted for bird's-eye view because birds are very visually oriented – they use their vision to look for food and look for food – and unlike human eyes, birds eyes can see a fourth color
We have three types of color receptors or cones in our eyes ̵
Some birds, such as the Australian honey-eaters, have their fourth color receptors, which are sensitive to violet light. In others, such as parrots, these cones can continue to detect in the UV region of the spectrum.
To find out how these violet- and UV-sensitive cones are translated visually, researchers dense forest habitat in both Sweden and Australia photographed a multi-spectral camera with specially designed filters to mimic what a bird can see.
What they discovered was pretty obvious.
The multispectral images clearly show how the UV sensitivity captures a greater contrast between the upper and lower surfaces of the leaves, highlighting the position and orientation of each leaf very clearly and three-dimensionally become.
"What seems to be a green confusion for humans are clearly distinguishable leaves for birds, and no one knew about it until this study," said biologist Dan-Eric Nilsson, also from Lund University.
Both the upper and lower leaf surfaces reflect similar amounts of UV light, so the researchers believe that the differences are due to the amount of UV radiation of the leaves versus permeability was transmitted through them.
By comparison, our bead eyes can not tell the difference since green light is both transmitted and reflected by the same amount, which produces much less contrast when viewed through green frequencies.
"[UV vision] Birds are likely to help them fly and bounce through dense foliage with greater agility," Tedore told ScienceAlert.
"Many birds look for insects and spiders that hide on the lower surfaces of the leaves, and these surfaces should be able to locate them quickly. In search of efficiency."
Through computer modeling, Nilsson and Tedore also found that The maximum sheet contrast at short UV wavelengths in well-lit, open roofs and at longer UV wavelengths can be seen hs in dimly lit, closed canopies. This may explain why the fourth color is perceived differently by birds.
What we see in the visualized UV images is, of course, only a bird's-eye simulation, as our eyes are not fully aligned with the task.
"Because birds have four cone classes (red, green, blue and UV) and we only have three (red, green, blue), we can only represent three cone channels of the birds at the same time," Tedore explains. "It's impossible for us to create a realistic representation of what the four-cone channel vision might look like."
But even if we can not really see these extra colors ourselves, we could still use the bird super color – vision through technology.
"The enhanced 3D structure in the UV range could be visualized by remote-controlled or autonomous vehicles to help them better navigate complex forest environments without getting caught in leaves," says Tedore.
So amazing In four shades, it also looks likely to have disadvantages.
"A drawback of a fourth cone class is that it takes up space in the retina, which could have been occupied by the other three cone classes." says Tedore. "This can be detrimental to the resolution and sensitivity in low light conditions."
Tedore says the next step in understanding bird's-eye view will be to see how their food sources show up in the UV. And they could also continue to explore how bird's eye view varies between species and environments.
"We may have the notion that what we see is the reality, but it is a most human reality, other animals live in other realities, and now we can see through their eyes and reveal many secrets. The reality is in the eye of the beholder, "concludes Nilsson.
Your article was published in Nature Communications.