CAPE CANAVERAL, Fla. -- Baby steps taken by rats aboard space shuttle Columbia may pave the way one day for extraterrestrial kids.
"In the future, obviously you would like to have some sort of family life on the moon or on Mars," New York University Medical Center's Kerry Walton said Thursday.
By identifying critical periods of development in space -- Walton is doing this with young rats aboard Columbia -- "we would know how long a child of a particular age could be in an environment other than Earth."
"This way, maybe people could grow up to be dual-adapted so that they could switch from an Earth environment to a low gravity in the same way that children nowadays can switch between one language and another," said Walton, a neuroscientist who's monitoring the experiment from Johnson Space Center in Houston.
During Columbia's two-week Neurolab mission, Walton is studying how young rats learn to walk in weightlessness.
Five of her older test subjects -- 20-day-old rats, their eyes recently opened -- used their front legs Wednesday to scoot around a small jungle gym aboard Columbia. They hardly used their hind legs, the astronauts reported.
"The animals decided to move around in the space lab the same way as astronauts do," Walton said. "So it seems all mammals that we've tested so far choose the same way to walk around in space. We're very excited about this."
Friday's shuttle experiment promises to be even more exciting. Eight 16-day-old rats will take their first steps ever -- in weightlessness.
The rats in Wednesday's trial, by contrast, were old enough to have walked on Earth before being rocketed into orbit last Friday.
"The question is, how much of development is hard-wired?" Walton said. "That is, how much is genetic and how much is influenced by our interaction with our environment?"
Columbia's astronauts will videotape the baby rats as they try to walk on the jungle gym. The animals' joints will be marked with black ink so each motion can be analyzed after the flight, and compared with their motions after they return to Earth. It's the same sort of technique used by athletes to improve performance.
"We think it's really neat because these animals, their nervous systems are going to develop and essentially they're going to think they were born in zero gravity," Walton said.
Despite such mind tricks, Walton suspects these younger rats will readapt to Earth's gravity just fine.