Monday, November 23, 2015

Water Bears' Weird DNA Allows Them To Survive In Space

   Water bears are tiny little micro-animals that are also the only species known to survive in space. Recent studies state that water bears also possess the highest amount of foreign DNA than any other species. About one-sixth of the water bear's genome comes from other animals. This is due to horizontal gene transfer occurring when the water bears are placed under conditions of extreme stress. Researchers believe that under extreme stress, their DNA breaks into small pieces and when the cells rehydrate, they become momentarily permeable which allows other DNA and large molecules to enter. Water bears have the ability to repair their own DNA as well as the ability to patch in foreign DNA while their cell membranes are still "leaky." Like water bears, the human genome also contains foreign though, obviously, not nearly as much.
   This mix of different DNA may be the reason why water bears are able to survive in the extreme conditions that are impossible for other species to survive. The addition of bacterial DNA within the water bear's genome may be the reason why this animal has the ability to survive in space .In 2007, a colony of water bears were shot into space and when they returned, not only were many of them still alive, but some had laid eggs while in space and the offspring were healthily hatched. Water bears can also be placed in a freezer for a year, then taken out and thawed. After 20 minutes, they unfreeze and carry on as nothing happened.
   I have learned briefly about water bears in the past, but this article goes more in depth about the interesting genome of the tiny animals. I did not know that water bears were the only animals able to survive in space and it was also interesting to know of the possible reason why. Further research can lead 


1 comment:

  1. This was a very interesting article. I had learned about water bears in biodiversity and evolution and even got to see one under a microscope. I knew they could live in space and be frozen and then thawed out and be fine but I had no idea about there genome. They are very interesting as well as impressive organisms.