A relative of the elephant, the woolly mammoth is one of the most famous extinct creatures in Earth’s history.

How exactly the species died out 4,000 years ago is something of a mystery, but a study presents an interesting new theory.

Researchers in Europe point the finger at plant pollen, which they say gave the mammoths allergies that damaged their sense of smell.

This made it more difficult to smell a mate from a distance which affected breeding rates, eventually leading to population decline and collapse.

Scientists have debated the extinction of the woolly mammoth for decades, but the new study adds to prevailing theories including hunting by humans.

Woolly mammoth: Basic facts

Woolly mammoth (Mammuthus primigenius) is an extinct species of elephant found in fossil deposits in Europe, northern Asia, and North America.

The species was known for its large size, fur, and imposing tusks, which were curvier than today’s elephants.

Thriving during the Pleistocene ice ages, woolly mammoths died out after much of their habitat was lost as Earth’s climate warmed in the aftermath of the last ice age.

 

The new study was conducted by scientists at Israeli firm SpringStyle, Russian Academy of Sciences, the University of Catania and Polytechnic University of Milan in Italy.

The team point out that today’s elephants – which share a common ancestor with the mammoths – have ‘the most sensitive sense of smell’.

‘During the breeding season, susceptibility to odors is very important for animals,’ they say in their paper, published in Earth History and Biodiversity.

‘Development of allergies from plant pollen… could lead to decrements in sensitivity to odors in animals during the breeding season.

‘This may explain the extinction of animals due to a decrease in Sєxual intercourse.’

Woolly mammoth (Mammuthus primigenius) was one of the last in a line of mammoth species to exist before its extinction around 4,000 years ago.

Around 13 feet (four metres) tall and weighing around six tons, the mᴀssive mammal was widespread in northern Europe, Asia, and North America during the last Ice Age.

Woolly mammoths co-existed with early humans, who hunted them for food and used their bones and tusks for making weapons and art.

However, the cause of their extinction is uncertain, with intense debate on the roles of human hunting and severe climatic change.

For the new study, researchers analysed tissue samples from mammoth corpses recovered from permafrost in north-eastern Siberia.

They found traces of immunoglubulins, also known as antibodies – the Y-shaped proteins used by the immune system to fight infections.

They also detected allergens such as plant metabolites, volatile organic compounds and pollen that the mammoths would have ingested from the air.

Together, these results suggest indicate the presence of allergic diseases and the ᴀssociated symptoms, including loss of sense of smell.

It’s possible that pollen-rich plants that flourished as the climate steadily warmed increased the problem for woolly mammoths.

‘Probably these changes in allergic responses of mammoths at period of climate changes led to a decrease in the mammoth population and, as a result, to their disappearance,’ the authors say.

However, they acknowledge the prevailing theories of why the species went extinct, including ‘hunting of mammoths by primitive people’.

The debate is likely to rage on however, with physical evidence providing a range of compelling arguments.

In 2015, British researchers claimed to put ‘the nail in the coffin’ on the debate after comparing extinction events in different areas with the spread of humans.

They laid the blame squarely on humans after finding that whenever prehistoric people spread to on continents and islands, the creatures quickly died out.

Yet another genetic study in 2008 concluded that climate change and disease was the most probable causes of extinction.

More recently, a 2021 study concluded melting of icebergs as the climate rapidly warmed wiped out the vegetation on which the mammoths relied.