Using owls as a model, a new research study reveals the advantage of stereopsis, commonly referred to as stereovision, is its ability to discriminate between objects and background; not in perceiving absolute depth. The findings were published in a recent Journal of Vision article, Owls see in stereo much like humans do.
The purpose of the study, which was conducted at RWTH Aachen (Germany) and Radboud University (Nijmegen, Netherlands), was to uncover how depth perception came into existence during the course of evolution.
"The reason why studying owl vision is helpful is that, like humans, owls have two frontally placed eyes," said author Robert F. van der Willigen, PhD, of Donders Institute for Brain, Cognition and Behavior at Radboud. "As a result, owls, like humans, could appreciate the 3-dimensional shape of tangible objects through simultaneous comparison of the left and right eye."
van der Willigen studied two trained barn owls (Tyto alba) by conducting a series of six behavioral experiments equivalent to those used on humans. He used computer-generated binocular random-dot patterns to measure stereo performance, which showed that the owl's ability to discriminate random-dot stereograms is parallel to that of humans despite the owl's relatively small brain. The results provided unprecedented data on stereovision, with findings that debunk the long-held consensus that the evolutionary advantage of seeing in stereo must be depth vision.
He contends the findings demonstrate that while binocular disparity, the slight difference between the viewpoints of the right and left eyes, does play a role in perceiving depth, it allows owls, like humans, to perceive relative depth rather than absolute distance. "It is useful, therefore, not so much in controlling goal-directed movements as it is in recognition."
In looking at future studies, van der Willigen hopes that scientist will consider that human or primate vision is not the only way to examine the stereovision experience. "My present work on the owl highlights underappreciated, but fundamental aspects of stereopsis," he says. "Nonetheless, final proof should come with behavioral demonstration of equivalent stereoscopic abilities in animals other than the owl. Hopefully, my current work will encourage scientists to investigate other animal species."
Association for Research in Vision and Ophthalmology: http://www.arvo.org
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
I answers my question. "What purpose of stereo vision?"
A veteran EMT and ambulance driver in Boston, Ed McCarthy is in a great position to understand his hometown spatially. But he’s also a history geek, and while constantly driving around the city’s neighborhoods, he loves recognizing the streets, buildings and other locales from the history books he so often buries his nose in.
The extinction of the biggest shark known to science may have triggered whales to grow to their current hefty sizes, a study suggests.
The UK's chief scientist says the oceans face a serious and growing risk from man-made carbon emissions.
Modifying neurons to flash as electrical impulses pass along them lets researchers grow light-up brains in a dish and eavesdrop on their chatter
They lived on a remote dot of land in the middle of the Pacific, 2,300 miles (3,700 km) west of South America and 1,100 miles (1,770 km) from the closest island, erecting huge stone figures that still stare enigmatically from the hillsides.
In a bleak, treeless landscape high in the southern Peruvian Andes, bands of intrepid Ice Age people hunkered down in rudimentary dwellings and withstood frigid weather, thin air and other hardships.
A viral video shows people lauding fare billed as an "organic" fast-food option that was actually McDonald's. It wasn't just pranksters playing tricks on these poor folks, but maybe their brains, too.
Deinocheirus mirificus, or unusual horrible hand, had long, clawed forearms, a sail on its back and a duck-like bill
Open letter says claims made for brain games are not based on sound evidence and that playing them may have opposite effect
A significant Bronze Age pottery find is made during an archaeological dig on the east side of Lewis, in Scotland.