That's a Tough Tardigrade
Last month, Evolution News explained the problem of accounting in evolutionary term for the superpowers of tardigrades, or "water bears." These incredibly tough little creatures, just a millimeter long, are capable of surviving under the most trying circumstances on Earth -- and off Earth, in outer space, that is to say in a vacuum. Yet they originated in the Cambrian explosion, just like that, presumably ready for action.
Here's a video from researchers who revived tardigrades that had been frozen for thirty years:
The Abstract in the journal Cryobiology reporting this achievement elaborates:
Long-term survival has been one of the most studied of the extraordinary physiological characteristics of cryptobiosis in micrometazoans such as nematodes, tardigrades and rotifers. In the available studies of long-term survival of micrometazoans, instances of survival have been the primary observation, and recovery conditions of animals or subsequent reproduction are generally not reported. We therefore documented recovery conditions and reproduction immediately following revival of tardigrades retrieved from a frozen moss sample collected in Antarctica in 1983 and stored at −20 °C for 30.5 years. We recorded recovery of two individuals and development of a separate egg of the Antarctic tardigrade, Acutuncus antarcticus, providing the longest records of survival for tardigrades as animals or eggs. One of the two resuscitated individuals and the hatchling successfully reproduced repeatedly after their recovery from long-term cryptobiosis. This considerable extension of the known length of long-term survival of tardigrades recorded in our study is interpreted as being associated with the minimum oxidative damage likely to have resulted from storage under stable frozen conditions. The long recovery times of the revived tardigrades observed is suggestive of the requirement for repair of damage accrued over 30 years of cryptobiosis. Further more detailed studies will improve understanding of mechanisms and conditions underlying the long-term survival of cryptobiotic organisms.
They not only survive but on waking, go about repairing the damage entailed by three decades of such abuse. This confirms what we said earlier:
What researchers should be focusing on is the amazing design of these tiny animals. They have stubby legs with claws. They have a mouth and eyes. They lay eggs. They molt periodically. They have a digestive tract and sexual organs. They have muscles and nerves. That's a lot of specialized tissue to pack into half a millimeter! And to think that these are among the most durable animals on Earth, able to survive in habitats beyond all necessity for a Cambrian marine organism, including outer space -- that should challenge all notions of unguided evolution. Organisms should only adapt to their immediate circumstances, not to distant unknown habitats they might encounter some future day, or never.
Warning: Don't try this trick with food that's been sitting around in your freezer for a similarly lengthy period of time.