Some bacteria have a remarkable capacity to survive being frozen or dried, something that could become a problem as the Arctic unfreezes. One of the most ambitious experiments ever designed, a plan to study this process over a period of 500 years, began in 2014. All the participants will be long dead before the experiment is even a quarter of the way through, but the first results have already been published.
If societies flourish when we plant trees under whose shade we'll never sit, the scientific equivalent may be to start experiments no one participating will get to complete. Some experiments date back more than 100 years. These are modest, however, compared to a project at the University of Edinburgh where 400 vials of dried Bacillus subtilis bacteria are intended to be kept and tested for half a millennium.
The bacteria were dried so they formed spores, whose protective outer layers keep out damaging chemicals and at least some radiation. When the time comes to revive, the spores have mechanisms to repair DNA that has been damaged, which the scientists want to study.
Not all the samples are to be left for five centuries untouched. Instead, every two years for the first 24 years some vials will be opened to see how they have been affected by their period in suspended animation. After this, the opening times will shift to every 25 years until the study is done. Even if some disaster prevents the experiment’s completion, plenty of valuable information will have been collected on the way.
The first opening of three vials took place in 2016, and the results have recently been published in PLOS ONE. These were compared with samples of the same bacteria stored under even more trying conditions for shorter periods. Storage at -80ºC (-112ºF) made no noticeable difference, and after more than a year in a near-total vacuum, 18 percent were still alive.