The rat-rodent and Absence of Evidence

Latest in the absence of evidence files (part of an ongoing series) is the rat-rodent. Scientists only had fossils of this creature, and so assumed that it had become extinct about 11 million years ago. There was no evidence that it existed any more recently, and they did not see any in the wild today.

They just discovered them, though:

"It has the face of a rat and the tail of a skinny squirrel - and scientists say this creature discovered living in central Laos is pretty special: It's a species believed to have been extinct for 11 million years.

The long-whiskered rodent made international headlines last spring when biologists declared they'd discovered a brand new species, nicknamed the Laotian rock rat.

...

The resemblance is "absolutely striking," Dawson said. As soon as her team spotted reports about the rodent's discovery, "we thought, 'My goodness, this is not a new family. We've known it from the fossil record.'"

They set out to prove that through meticulous comparisons between the bones of today's specimens and fossils found in China and elsewhere in Asia.

To reappear after 11 million years is more exciting than if the rodent really had been a new species, said George Schaller, a naturalist with the Wildlife Conservation Society, which unveiled the creature's existence last year. Indeed, such reappearances are so rare that paleontologists dub them "the Lazarus effect."

"It shows you it's well worth looking around in this world, still, to see what's out there," Schaller said.

The nocturnal rodent lives in Laotian forests largely unexplored by outsiders, because of the geographic remoteness and history of political turmoil.

Schaller calls the area "an absolute wonderland," because biologists who have ventured in have found unique animals, like a type of wild ox called the saola, barking deer, and never-before-seen bats. Dawson describes it as a prehistoric zoo, teeming with information about past and present biodiversity.

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Read it all.

This is why it is difficult to claim that something absolutely does not exist just because you have not seen it -- in archeaological evidence, in fossil evidence, etc.. Quite often, new evidence arises to show that assumption incorrect -- and those are only the times that evidence happens to arise.

Perhaps a summary post soon with links to the posts in the "Absence of Evidence" series.