New Research Finds People And Pigeons See Eye To Eye
By Lori Wright, Media Relations
February 21, 2007
Pigeons and humans use similar visual cues to identify objects, a finding
that could have promising implications in the development of novel technologies,
according to new research conducted by a UNH professor.
Brett Gibson, an assistant professor of psychology who studies animal
behavior, details his latest research in the journal article, “Non-accidental
properties underlie shape recognition in mammalian and non-mammalian vision,” published
today in Current Biology. Gibson and his colleagues found that humans and
pigeons, which have different visual systems, have evolved to use similar
techniques and information to recognize objects.
“Understanding how avian visual systems solve problems that require
considerable computational prowess may lead to future technological advances,
such as small visual prosthetics for the visually impaired, in the same
way that understanding visual processing in honeybees has led to the development
of flying robots and unmanned helicopters,” the researchers say.
So a software engineer who wants to design a program to help a robot recognize
objects can get a leg up from evolution, which has been developing “programs” for
object recognition in animals long before humans ever thought of doing
such things, Gibson says. “To the extent that we can learn how different
animals recognize objects and whether they are doing the same things or
different things based on their environments may really help us in designing
our own system of object recognition.”
Gibson and his colleagues from the University of Iowa (Olga Lazareva and
Edward Wasserman), the University of Montreal (Frédéric Gosselin),
and the University of Glasgow (Philippe Schyns) found that pigeons, like
humans, primarily rely on corners (coterminations) of an object in order
to recognize it instead of relying on other features such as shading and
For example, a person could easily identify a AA battery from the side
profile. But, let’s say the person could see the same battery only
from the bottom with the negative terminal. From this perspective, the
only visible outline would be a circle; from the bottom, the corners of
the battery now are not visible and information about the corners cannot
“The task of recognizing the object becomes much more difficult.
For most people, it would take them a bit longer to recognize the image
as a battery,” Gibson says.
The researchers employed a new procedure, which Gosselin and Schyns developed,
called Bubbles, to determine what features humans and pigeons were using
to recognize objects. Three pigeons were trained to recognize four objects:
an arch, a barrel, a brick, and a wedge. The researchers then partially
revealed different parts of the object pictures. They then conducted the
same experiment with six people.
Not only did both the pigeons and people recognize the four objects based
mostly on corners, but they used these properties more than the shading
information contained in the images. More notably, the pigeons and people
used corner information more than a computer programmed to extract the
most useful information for recognizing the object pictures, which suggests
that the pigeons and people were using comparable information.
“When members of different species respond similarly to the same
visual information, we gain confidence in the prominence of this information,
irrespective of cultural or genetic influences. Birds represent an important
group to compare with mammals, the other major class of warm-blooded, highly
mobile, visually oriented animals,” the researchers say.
“Because of the unique demands of flight, for the last 200 million
years birds have been under strong evolutionary pressures to keep their
overall size to a minimum. Although a very large portion of the avian central
nervous system is devoted to visual processing, the bird brain is still
just a fraction of the size of our own. It is this extraordinary mixture
of visual competence and small size that makes the study of birds critical
to our understanding of the general mechanisms of visual cognition,” they
In addition to his research on vision, Gibson has done extensive research
involving navigation and memory in birds. He is currently investigating
how the Clark’s nutcracker uses different types of spatial information
to return to hidden stores of food during winter. More information: http://www.unh.edu/news/cj_nr/2006/october/lw10bird.cfm?type=n.