Woolly thinking?

Matthew Wooller was ready to go. In front of him was a huge tusk which had been found in AlaskaA US state in the extreme northwest of the continent of North America. It is separated from the rest of the USA by Canada. . DNA tests showed that it came from a female woolly mammothIts closest living relative is the Asian elephant. The last population lived on Wrangel Island in the Arctic Ocean. they called Elma. Now, by sawing into the tusk and analysing it, they hoped to find out much more.

Woolly mammoths' tusks grew a little bit every day, with a thin layer of minerals building up on the tip. Dr Wooller compares it to ice-cream cones stacked on top of each other.

Elma's tusks contained traces of strontium, an element found in some minerals. These minerals are found in some plants. If a mammoth spent the day grazing in a place with a lot of strontium, that would be reflected in the cone of minerals added to its tusk that day.

Scientists had the idea of comparing the strontium level in a tusk with that of the local area. They could then work backwards to find where a mammoth had come from.

Elma was born in the Yukon region of Canada. She later walked hundreds of miles west into Alaska.

She died aged 20. There were traces of human activity near her remains, so she may have been killed by hunters.

Woolly mammoths lived in North America for around 100,000 years. They survived the Ice AgeA long period of time in which global temperatures are extremely cold. thanks to their thick coats. They overlapped with the first humans in Alaska for about 1,000 years before dying out.¹

Most of the world's woolly mammoth populations disappeared by 8,000 BC. But in very remoteFar away from places where humans live. places some survived far longer. Remains dating from 4,000 BC have been found on the Arctic island of Wrangel. 

Whether they were hunted to extinctionCompletely dying out. is a matter of debate. Early humans certainly saw them as important prey, and often made cave paintings and carvings of them.

But it is also possible that they were victims of climate change. With the end of the Ice Age, much of the land where they used to feed was reduced to bogAn area of wet, muddy ground. .

Could this reshape history?

Yes: If widely used, Dr Wooller's technique could give us a hugely improved understanding of woolly mammoths' migratory patterns and how the Ice Age affected different parts of the planet.  

No: We would need far more tusks than have ever been found to draw any useful conclusions - and information from a single species would only be a tiny part of a huge jigsaw.

Or... Not in itself, but as a piece of detective work it is absolutely amazing. It could open other scientists' eyes to new ways of approaching things which would bring enormous benefits to humanity.