What is the Ultimate Animal?

In my continuing series, Difference Between Humans and Animals, I've been trying to understand what does and what does not make humans unique. I've discussed many surprising animal abilities, but I haven't stopped and considered which is the best survivor? A recent article in the NYT times has convinced the answer may be none other than the common gray squirrel:

behind the squirrel’s success lies a phenomenal elasticity of body, brain and behavior. Squirrels can leap a span 10 times the length of their body, roughly double what the best human long jumper can manage. They can rotate their ankles 180 degrees, and so keep a grip while climbing no matter which way they’re facing. Squirrels can learn by watching others — cross-phyletically, if need be. In their book “Squirrels: The Animal Answer Guide,” Richard W. Thorington Jr. and Katie Ferrell of the Smithsonian Institution described the safe-pedestrian approach of a gray squirrel eager to traverse a busy avenue near the White House. The squirrel waited on the grass near a crosswalk until people began to cross the street, said the authors, “and then it crossed the street behind them.”

Not only are they communal, they are also selfish:

But the squirrels don’t just bury an acorn and come back in winter. They bury the seed, dig it up shortly afterward, rebury it elsewhere, dig it up again. “We’ve seen seeds that were recached as many as five times,” said Dr. Steele. The squirrels recache to deter theft, lest another squirrel spied the burial the first X times. Reporting in the journal Animal Behaviour, the Steele team showed that when squirrels are certain that they are being watched, they will actively seek to deceive the would-be thieves. They’ll dig a hole, pretend to push an acorn in, and then cover it over, all the while keeping the prized seed hidden in their mouth.

But perhaps their greatest strength, is that world's most dangerous predator, man, doesn't consider them a threat.