Special Type of DNA in Owl Eyes May Be a 'Lens' That Supercharges Night Vision

 Owls are one in every of the rare avian predators that catch their prey by night, and new research suggests that there is something special within the way the DNA molecules in their eyes are packaged, giving them a strong visual advantage within the dark.

Through the method of natural action, the new study proposes that the DNA within the retinal cells of owls may are put together in such how that it acts as a kind of lens or vision enhancer, improving eyesight during the night.

The unusual trait hasn't been seen in birds before, which hints that owls have gone it alone on this particular evolutionary path, a minimum of among birds. the bulk of birds are diurnal like we are – is most active within the day and sleeping it all off in the dark.

"In the ancestral branch of the owls, we found traces of positive selection within the evolution of genes functionally associated with seeing, especially to phototransduction, and to chromosome packaging," write the researchers in their paper.

The team checked out the genomes of 20 different bird species, including 11 owls, identifying where positive selection had occurred – where beneficial mutations had been kept over generations. for sure, lots of this is going on within the areas of sensory perception, which is why owls can hear and see so well.

But the team also discovered signs of accelerated evolution in 32 genes that were more of a surprise. These genes were linked to DNA packaging and chromosome condensation – as if the structure of the molecules inside the owl eyes had actually adapted themselves to be able to capture more light.

A similar change in DNA molecule arrangement in retina cells has been seen before in nocturnal primates, and computer models of their molecular structure have suggested they will channel light.

This isn't the sole evolutionary boost that owls have for peering through the gloom – they even have retinas packed with rod cells for better twilight vision, for instance – but it'd definitely help in catching prey after dark.

Although the researchers' claims remain hypothetical, it's an intriguing idea. The comparison of genomes also supports the concept that owls did indeed evolve from an ancestor that was diurnal - seeing because the largest changes observed in their genetics seem to be associated with enhancing night-hunting abilities.

While owls kept the sharp talons they share with day-hunting birds of prey, like eagles and falcons, the researchers found genes that differed from owls' ancestors, and one which may potentially enhance their excellent hearing, visual sense, and soft feathers for silent flight. If the study's findings are confirmed, even the DNA molecules seem to be boosting the wonderful sight capabilities of owls.

The authors caution their proposed roles for the different genes are only suggestions for the instant, particularly with respect to how photoreceptors in owl eyes actually function. Direct observations and analysis is also ready to build upon the findings outlined here and will tell us even more about how owls gained their evolutionary advantages.

"Our study suggests novel candidate genes whose role within the evolution of owls is further explored," write the researchers.