According to researchers, rising sea levels proved to be fatal for mammoths in Alaska who were cut off from fresh water supplies.

It turns out that as sea levels rose and the island shrank, mammoths were concentrated in a tiny area of land with limited access to fresh water.


The new study managed to come to the bottom of one of the best-dated prehistoric extinctions with the aid of state-of-the-art techniques on ancient Mammoth DNA which was left extremely well preserved in the lake core of St. Paul Island, but it also proved how vulnerable small populations are to environmental change on smaller islands.

Mammoths were huge creatures that could reach nine meters in length and five in height and could make the earth tremble with their nearly eight tons of weight.

But most of them became extinct at the end of the last ice age (about 12,000 years ago).

However, a small population of mammoths, wooly mammoths, survived on the island of Saint Paul (Alaska) until 6000 BC.

Their misfortune and salvation was being trapped there after sea levels rose and cut off their access to the mainland, which eventually trapped them in without drinking water supplies.

Until now, there has been no agreement on why these animals disappeared, but it seems that climate change and hunting carried out by humans had much importance to the existence of mammoths than previously thought.

According to a new study published in the Journal “Proceedings of the National Academy of Sciences, ” Alaska wooly mammoths died due to sea level rise because this prevented them from accessing sources of fresh water.

According to an article by the University of Alaska Fairbanks:

Nitrogen isotope analyses of dated mammoth bones and teeth also signaled progressively drier conditions leading up to the extinction event. Wooller said these “multiple lines of evidence” of decreasing lake levels provide a strong case for what led to the animals’ extinction.

“It paints a dire picture of the situation for these mammoths,” said Dr. Matthew Wooller, from the University of Alaska Fairbanks, who co-led the research.

“Freshwater resources look like the smoking gun for what pushed them into this untenable situation.”

“It’s amazing that everything turned out so precisely with dating of extinction at 5,600 plus or minus 100 years,” said co-author Prof Russell Graham, from Pennsylvania State University in the US.

According to earlier research, the remains of five mammoths from St. Paul Island were dated to about 6,480 years ago.

Journal reference:

http://www.pnas.org/content/early/2016/07/27/1604903113.full

Study: Lack of water likely caused extinction of isolated mammoths