The Dingo-Kelpie mongrel picked out the unpleasant aroma of bacteria in mud from Queensland – bacteria that matched fossils of primitive organisms in Martian rock that plunged into Antarctica 13,000 years ago.

Known as Tamarind to biophysicist owner Tony Taylor, the Australian dog could have saved NASA the bother of sending probes to the red planet - if only it had sniffed around filth in Moreton Bay sooner.

And NASA scientists who examined the potato-sized meteorite discovery, called ALH84001, agree this may well be proof that life really did exist on Mars.

Well-trained

Taylor said Tamarind came along on all his field trips, so training him to smell out sediments containing specific bacteria was quite easy. "It smells like sewage and she knows the word 'stinky'."

Based at the Australian Nuclear Science and Technology Organisation in Sydney, Taylor says he and colleague Professor John Barry have examined 82 different bacteria, retrieved from the area identified by the dog.

"When we say life, we're talking about bacteria, single cell primitive life forms, like we have here on Earth. It'd be underground, we'd have to drill down, so these little rovers that are crawling all over the surface would never find it"

Tony Taylor,
biophysicist

They discovered they contained 11 characteristics also found in the Mars fossils, including a structure other scientists claimed could only be formed in intense heat.

"They were a perfect match, absolutely perfect. Eleven features out of 11," said Taylor, whose work, crediting Tamarind, was published on Thursday in the "Journal of Microscopy".

"These fossils are four billion years old. They pre-date the fossil record of life here on Earth."

Imaging technique

The bacteria-studying duo developed an imaging technique that allowed them to examine the bacteria at a much higher resolution - and they were delighted with the findings.

The scientists now believe the combined data warrant a manned mission to Mars to retrieve further samples.

"The results indicate very strongly that life was once there and... that life might still be there," Taylor said. "When we say life, we're talking about bacteria, single cell primitive life forms, like we have here on Earth."

"It'd be underground, we'd have to drill down, so these little rovers that are crawling all over the surface would never find it."

Two US-backed rovers are now exploring the red plant and transmitting unprecedented images of the barren landscape, but may achieve little else.