When people think of birds, one of the main things that comes to mind is their eyesight. Many birds have sharp vision; especially those that glide at extreme heights as predators and swoop down to catch their prey, but a new study finds that not all birds are like that.
Smaller birds, such as the blue tit, collared flycatcher, and pied flycatcher, may not have as sharp of vision as their cousins, but their eyesight may compensate for lack of sharpness with speed.
A study published in the journal PLOS ONE suggests that smaller birds may have eyesight that is up to two times zippier than that of a human’s eyesight, but that the sharpness of their eyesight may not be as sharp as once thought. As a result, birds can identify more details about an environment in time space much more quickly.
In this respect, these species of birds are able to spot movements and recognize them much more efficiently than humans, which gives them the upper hand in escaping predators. On the other hand, they don’t necessarily have the ability to identify what exactly the predator is because they don’t spend a whole lot of time focusing on it to get a clear enough image.
In the study, the researchers measured the birds’ temporal resolution by using a lamp flicker rate to measure how much the birds were able to distinguish apart from one another.
As the flicker rate was increased, scientists were able to start looking for patterns of when the birds were unable to distinguish them apart – at this point, the temporal resolution maxes out and the scientists get their numbers.
The findings show that smaller birds are efficient at identifying things in shorter periods of time, whether their vision is blurry or not. Nevertheless, they don't necessarily have as clear of eyesight as humans.
“Fast vision may, in fact, be a more typical feature of birds in general than visual acuity,” said lead researcher Anders Ödeen. “Only birds of prey seem to have the ability to see in extremely sharp focus.”
So do birds see better than humans? – It really depends in what context you choose to talk about. For some species, their visuals may not be as clear, but their ability to perceive time space more quickly make them more effective at identifying things more quickly.
Source: EurekAlert via Headlines & Global News