Moss from Antarctica, believed to be 1500 years old, has been brought back to life by scientists. 

This is the longest lifespan ever recorded for a plant. Until now, it was believed that moss could only be revived after 20 years or so of being frozen.  

Mosses are a vital part of the ecosystems at both the north and south poles. In many areas, they are the dominant variety of plant, and provide one of the bases of the food chain in those frozen areas. Mosses also represent the greatest storehouse for carbon dioxide in those regions. This collection of mosses stayed under an ice shelf for 15 centuries. Researchers believe this collection of moss was already several decades old when it became trapped under the ice. Bacteria have been revived after thousands, or even millions, of years. 

"What mosses do in the ecosystem is far more important than we would generally realize when we look at a moss on a wall here, for instance. Understanding what controls their growth and distribution, particularly in a fast-changing part of the world such as the Antarctic Peninsula region, is therefore of much wider significance," Peter Convey from the British Antarctic Survey, co-author of the study, said. 

In order to carry out their study, Convey and his group took core samples from mosses found deep under an ice shelf on Signy Island, off the Antarctic Peninsula. After bringing the samples back to the lab, they carefully sliced the collection of frozen moss. Researchers had to be careful not to allow any contamination, especially by microscopic lifeforms. These samples were then placed in an incubator, where they were warmed and provided with a normal amount of light. In less than a month, the moss samples were growing once again. Soon, they were fully alive, for the first time since the fall of the Roman Empire. 

One of the most important aspects of this study is just how simple it was to revive the plants. Since the research team was able to revive the plants with simple warmth and light, they postulate nature could do the same. This could explain how affected areas recovered after ice ages. When ice retreated, it could leave behind moss, trapped in glaciers since they first advanced. This would eliminate the need for plants to expand into newly-thawed areas. 

Researchers believe that further, older samples may be revived. This could lead to plants from 4,000 to 5,000 years ago coming back to life. 

Details of the ancient moss was published in the journal Current Biology.