A Japanese research team has successfully revived small insects after being in deep freeze for nearly two weeks in what could be a step toward prolonging the life of larger animals.

Scientists say they believe the defrosting of water fleas by a team led by Professor Ichiro Tanasawa of the Tokyo University was the first time complex multicellular organisms have been revived after being frozen to minus 321 degrees.At that temperature, metabolism virtually halts, "and theoretically, organisms can be kept frozen for any length of time and then revived," Tanasawa says.

Tanasawa's team first chilled the water fleas to almost freezing, then soaked them for several hours in a glycerin solution.

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