In November 1957, a dog named Laika became the first living creature in space, although she had to be put to sleep before Sputnik II burned up in the atmosphere upon reentry.

There are now indications, however, that Laika and her fellow canine cosmonauts may have been dogdom's last space hoorah. It is not likely that dogs will be a strong contingent on the International Space Station and they are not even on the radar screen of those who are actively planning Mars colonization.

Dogs just don't meet the requirements Martian colonists will need from domesticated animals, says Mars Society member Thomas Gangale. Gangale presented his ideas in August at the International Mars Society conference. The ideal domesticated animal on Mars, Gangale said, has the following characteristics:

• Is well-studied in laboratory conditions,
• Is small, therefore easy to send to Mars,
• Breeds rapidly,
• Requires low maintenance (a fastidious self-cleaner),
• Produces premium manure,
• Eats most of what humans don't, thereby reducing the food waste of Martian colonists and contributing to the composting process,
• Poses miniscule health risk to humans (no mad dogs allowed), and
• Tastes great.

Given these characteristics, Gangale came to the conclusion that only one Earth animal fit the bill. "These qualities describe Oryctolagus cuniculus, the European or domestic rabbit," he explained.