Tuesday, December 13, 2016

One Tough Fly

As we prepare to survive the Ozark winter, I came across this incredible midge living in semi-arid regions of Central Africa.  Polypedilum vanderplanki is a true survivor.  It lives in tiny transient mud puddles in a region where the dry season may go 8 months without a drop of rain.  Its larvae can survive complete dehydration at high temperatures for months, then revive within an hour to its normal activity.  Its eggs, pupae and adults die in those same circumstances.

Once fully dehydrated, it can survive a whole string of tortures designed by fiendish (or well intentioned scientists) determining the limits to its life.  In a fully dehydrated state it can survive to reproduce in the following Olympic events for durability.
  • 17 years of complete dehydration
  • boiling for 3 hours at 106⁰ C
  • bathing in 100% ethanol for 17 hours
  • freezing at -190ºC for 77 hours.
Recently a cell line from the larva has been preserved after dehydration to 6% of residual moisture and kept for 251 days at room temperature.  When rehydrated it was able to resume swimming and proliferation, while its eggs, pupae and adults die in those same circumstances.  Sciencedirect.com

The secret to its success is a sugar called trehalose, as explained in this story in far more detail than I would even attempt.