Woolly thinking?

Matthew Wooller and his team were ready to go. In front of them was an enormous 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. . DNADeoxyribonucleic acid is the material in an organism that carries genetic information. 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., whom they nicknamed Elma. Now, by sawing into the tusk and analysing it, they hoped to discover 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. The cones can be seen distinctly in surviving tusks, rather like tree ringsA tree grows at different speeds throughout the seasons, leaving a visible ring for each year of its life..

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

Scientists realised that by comparing the strontium level in a tusk with that of the surrounding area, they could work backwards to discover where a mammoth had wandered in the course of its life.

Elma turned out to have been born in what is now the Yukon region of Canada. She later migratedMoved long distances. hundreds of miles west into Alaska.

She died at the comparatively young age of 20. The fact that her remains were found near traces of human habitation suggests that she may have been killed by hunters.

Woolly mammoths inhabited North America for around 100,000 years, surviving the Ice AgeA long period of time in which global temperatures are extremely cold. with the help of 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 remote 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 extinction is a matter of debate. Early humans certainly saw them as important prey, and often portrayed them in cave paintings and carvings.

But it is also possible that they were victims of climate change. With the end of the Ice Age, many of the dry grasslands on which they fed turned into bogs where they could not find food.

"In Alaska, mammoths would have gone extinct anyway regardless if humans were hunting them or not," claims a member of Dr Wooller's team, Audrey Rowe. "If anything, humans just hastened their demiseEnding or death. ."²

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 an enormous 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.