In studying the spatial memory of wild-caught mountain chickadees, University of Alberta researchers were surprised to discover the birds contradicting prior research that showed how animals navigate. This study is the first to reveal a different pattern. Previously, only animals that had been raised in human-made enclosures had been tested.
The findings are published in the July issue of Biology Letters.
To get their bearings, humans and other animals are often guided by the geometrical shape of their environment. For example, humans have an easy time distinguishing the door located at the ends of a hallway from those located in the middle, but may confuse doors at the two ends, such as when they re-enter a hallway in a hotel. "This has been observed in every species tested, even when landmarks alone could be used, suggesting that animals are predisposed to go by geometry," said co-author Dr. Chris Sturdy, a professor of psychology and member of the Centre for Neuroscience at the University of Alberta.
The wild-caught chickadees differed from all previously tested animals by ignoring angular features of their environment and following landmarks instead. Although able to learn geometry when guiding themselves to food in lab experiments, the birds consistently ignored the concept when a prominent landmark, in this case a blue wall, was present.
"Getting oriented is an important part of solving many spatial navigational problems, such as locating your car in the parking lot at the end of a long day in the office. This discovery points to the fact that our early experiences influence how we solve such problems and could mean that by varying the environments that we encounter early in life, we could broaden and hone our spatial navigation abilities," said Dr. Sturdy and Dr. Marcia Spetch, who supervised the work conducted by graduate students Emily Gray and Laurie Bloomfield.
The findings also suggest the need for more research outside of lab environments, Dr. Sturdy said. "We have to look away from lab species and look at the diversity out there. There could be a lot of other species that have other ways of doing things."