My Love of Mastodons and Mammoths
As a girl, I was fascinated by ancient creatures. I passed my love of dinosaurs and prehistoric mammals to my three young sons as well. I have, stored now, buckets of prehistoric creature replicas my sons played with as toddlers. My shelves are still populated with the books my boys and I would read repeatedly about dinosaurs and towering mammoths and mastodons – both fiction and non-fiction, it didn’t matter.
Prehistoric mammals were a particular favorite of mine. I still have some of the books I collected as a girl. I voraciously read Jean Auel’s Earth Children Series which includes the novel, The Mammoth Hunters. The first short story I wrote with my oldest son as the main character, A Book In Time: Connor and his Mammoth involved an ice age adventure with mammoths and a mysterious cave dweller.
So, when I came across an article describing the mastodon’s disappearance from Berengia, I had to blog about it. All the reading I had done for years stated two things:
- megamammals including mastodons and mammoths were driven to the brink of extinction by over-hunting by an ever-expanding human population;
- the climate change causing a warming environment finished them off
Berengia and the Megamammals including Mastodons
Humans entered North America from Asia through the Bering Land Bridge which appeared 20 to 25 thousand years ago at the end of the Pleistocene. The monumental glaciers during the ice age of that period locked up so much water that sea levels dropped over 300 feet exposing the unglaciated land tract that became known as the Bering Land Bridge. This bridge was part of a larger land mass between Alaska and northeast Asia called Berengia which contained tundra vegetation. Mammoths loved tundra vegetation. They thrived on it and humans found plenty of them in and around Berengia. Mammoths probably did die out due to human hunting and climate change around 10,000 years ago although a small population of these beasts survived until about 3700 years ago on Wrangel Island off the coast of Siberia.
Previous fossil evidence suggests all the huge mammals, including mastodons, died out after humans arrived on the scene. However, it is contradictory that mastodon teeth show these beasts preferred a diet of woody plants. They would have lived in coniferous or mixed woodlands with lowland swamps which definitely was not the nature of the human-inhabited Berengia. It is known that many megamammals, including mastodons, did migrate north about 125,000 years ago during the last interglacial period when temperatures matched those we experience today. Mixed wood forests would have been plentiful even that far north which would have supported these large mammals.
New Research Dating Mastodon Fossils
Grant Zazula, a palaeontologist in the Yukon Paleontology Program and his research team used two precise types of carbon-dating methods on 36 mastodon teeth and bones. These particular dating methods target only bone collagen and not other incidental material including preparation varnish and glues used to strengthen the specimens. Previous dating methods did not isolate bone material from these other non-bone materials. Zazula and his team found that all the mastodon fossils were older than previously determined. Most were older than 50,000 years (the limit of radioactive dating).
These results support the known facts of mastodon biology. They could not have lived during human occupation of Berengia because the tundra vegetation could not have supported them. The new evidence suggests they died out some 75,000 years ago in the Arctic and sub-Arctic when the climate became cooler again bringing back the glaciers and changing the landscape back to isolated tracts of sparse tundra vegetation. Humans were not responsible for the mastodon’s extinction in the Arctic. You can’t pin their demise on Homo sapiens.
American Museum of Natural History. “American mastodons made warm Arctic, subarctic temporary home 125,000 years ago: Local extinction long before human colonization.” Science Daily. Science Daily, 1 December 2014.