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IPFS News Link • Science, Medicine and Technology

This Leech Can Survive A 24-Hour Submersion in Liquid Nitrogen

• http://www.popsci.com, By Douglas Main
 At first glance there is nothing overly special about Ozobranchus jantseanus, a small parasitic leech of freshwater turtles in East Asia. But throw them into a vat of liquid nitrogen, and they can survive for 24 hours. This is most unusual, to say the least--most creatures cannot survive for very long below water's freezing point of 32°F (0°C), let alone temperatures of -321°F (-196°C), because when water becomes ice it crystallizes and usually ruptures cells. Only two other known species can survive being immersed in liquid nitrogen--water bears and the larvae of one type of drosophilid fly--but previously the maximum recorded length of submersion was 1 hour. 

But that's only the beginning of this species' amazing abilities to withstand cold. Every single leech placed in -130°F (-90°C) storage survived for nine months. In other words, these leeches can easily survive at temperatures lower than those ever measured by a thermometer on Earth, for as long as it takes to conceive and give birth to a human child. Some of the leeches survived at this temperature for 32 months, or more than 2.5 years.