Elephants in Manitoba — new research suggests extinction linked to arrival of first humans

 

by Bruce Cherney

In his Narrative of the Canadian Red River Exploring Expedition of 1857, Henry Youle Hind related the finding of “great bones” along Shell Creek in Manitoba.

Hind said the bones “had long been a source of wonder and awe to the Indians hunting on the left bank of the Assiniboine (River), and whose magnificent descriptions led me to suppose they might belong to a cetacean (whale), and were worth a day’s journey out of our track to visit and examine.”

 

At the time, Hind and his party of explorers were at Fort Ellice, a Hudson’s Bay Company trading post on the west bank of the Assiniboine where Beaver Creek enters the river valley near present-day St. Lazare.

As a geologist from Eastern Canada,  Hind was well aware that at various times in the distant past, what would later become Manitoba had been submerged by a tropical inland salt-water sea running from the Gulf of Mexico to the Arctic during the Cretaceous period. It was due to this knowledge that Hind speculated the “great bones” could have come from a whale.

Hind said the bones had been seen many years earlier “protruding from the bank of Shell Creek (now Shell River that enters the Assiniboine near present-day Shellmouth), 20 feet below the prairie’s level.”

This was another clue for Hind, who reasoned the great depth of the bones indicated an ancient beginning.

In the end, Hind did not take the journey to uncover the bones, but John McKay, an officer of the HBC at Fort Ellice, “instructed some of the hunters attached to the post to bring them to him, but no Indian would touch them, and the half-breeds (Métis) only brought a tooth and collar bone ...”

Hind was told the bones brought by the Métis had been shown to a doctor who informed them the bones were actually from a mammoth, an extinct species of elephant that had last roamed the area during the Ice Age 10,000 years ago.

“Mr. (W.J.) Christie, of Fort Pelly, we were told, went to Shell Creek, with a view to collect more specimens; he obtained some ribs, but in a state of crumbling decay; they were sent to Red River Settlement.”

The reason aboriginal people refused to disturb the bones, Hind said was because they “regarded these ancient relics as the bones of Manitou and worthy objects of veneration.”

Joseph Burr Tyrell, a geologist with the Geological Survey of Canada from 1881 to 1898, who made scientific history when he discovered the first dinosaur bones in North America, mentioned the mammoth bones found in the riverbank of the Shell River. Tyrell said Christie told him he had “visited the place (in 1853), and examined the spot carefully where the (shoulder) blade was taken out at low water. A land-slip had occurred from the bank and carried the bones into the river at low water. I found from cross-questioning my guide, that the Indians collected the bones, and burnt them on the bank, from superstition, and buried what would not burn. I examined the spot where they had buried the bones, but what remained crumbled to pieces when touched.”

Still, Hind was intrigued by the prospect of finding mammoth bones and adding them to his  collection of artifacts gleaned along his journey. When given a description of tasks for the exploration of the Northwest by the Canadian government (the assembly of the province of Canada — now Quebec and Ontario — in British North America, as the nation of Canada was not established until July 1, 1867), Hind was also charged to find and collect “natural history” fossils.

Hind later questioned an Ojibway named Ta-wa-pit, who described “some gigantic bones exposed in the bank of Valley River (which flows into Lake Dauphin) where it cuts through Old Lake Ridge ... 

When Ta-wa-pit previously visited the area to collect salt, he found evidence of the gigantic bones.

It would seem that Ta-wa-pit considered the bones less fearful than  other First Nations people. He believed the bones were “great medicine” and “now and then takes small fragments, bruises them into powder, and used them as a medicinal preparation.”

It’s not uncommon for cultures across the world to take ancient fossils and grind them up for medicinal purposes. In fact, bones from the famous Dragon Bone Hill cave near the village of Zhoukoudin, 50 kilometres southwest of Beijing, where the remains of Peking Man (Homo erectus pekinensis) were found, were used by the Chinese for decades to make medicine. It was from people living near the cave that the existence of ancient “dragon bones” — all fossils were called dragon bones by local residents — were uncovered by Westerners, including Dr. David Black, a Canadian anthropologist, who identified the 400,000-year-old remains in the 1920s of the humanoid as Peking Man.

Hind wrote: “From his (Ta-wa-pit’s)  description I infer that the bones are those of a mammoth; his rough drawing of the ribs and teeth in the sand corresponded, in point of

dimensions, with those of the gigantic animal.”

While Hind may have correctly identified the bones as being the fossilized remains of a mammoth, it is possible they were from a mastodon, another species of tusked-elephant-like animal that roamed ancient North America. The family Mammutidae that spawned the mastodon is extinct.

Both mammoths and mastodons were members of the order Proboscidea, alluding to their long trunks. Unlike mastodons, mammoths are closely related to living elephants, especially the Asiatic elephant. Mastodons are only considered distant cousins of modern elephants.

Mammoths, members of the family Mammuthus, were the larger of the two species; one sub-species in North America stood 4.6 metres at the shoulders. On the other hand, mastodons were about the size of a modern-day elephant at two to three metres at the shoulder. Both animals were cold-weather adapted, bearing thick coats of hair to conserve body heat.

Mastodons, which originated in North Africa about 35 million years ago, came to North America from Siberia over the Beringia land bridge 15 to 20 million years ago (re Yukon Beringia Interpretive Centre), while mammoths arrived by the same route some 1.7 million years ago.

The glaciation of the Pleistocene, which began 1.8 million years ago, caused massive amounts of water to be trapped in vast continental ice sheets, resulting in the exposure of land shelves that had previously been submerged. The sea level was 129 metres lower across the globe than it is today. One such shelf was Beringia, which linked North America and Asia, allowing the free movement of mammals between the two continents. When Beringia was at its peak between 26,000 and 10,000 years ago, it was a broad plain measuring 1,600 kilometres from north to south and twice as wide as modern-day Texas. At this time, two massive ice sheets covered most of Canada (15.5 million square kilometres). The Laurentide ice sheet stretched as far south as the Great Lakes and New Jersey, and west to east from the Prairie Provinces to Newfoundland and Greenland. The Cordilleran ice sheet was confined to the west by the Rocky Mountains. 

The upper tusks (actually enlarged upper incisor teeth) of mastodons extended outward for two metres or more in an almost straight line, while mammoth tusks (second upper incisor teeth) had pronounced curves and could measure up to 4.2 metres in length. 

The North American species of mastodon, which ranged from Alaska and the Yukon in the north to Mexico in the south, bears the scientific name Mammut americanum. Mastodons were confined to forested regions where they fed on tougher conifer twigs and needles and other tree species. The vegetation was ground up by their massive teeth.

Mammoth teeth were adapted to grinding up the coarse grasses in the tundra-like regions of North America that formed in the shadow of the continent-wide ice sheets. As temperatures rose and fell, the North American glaciers advanced and retreated throughout the Ice Age. In the last years of the Ice Age, just to the south of the ice sheets, were vast grasslands, ranging from what is now the central Great Plains and the Midwest stretching to the Eastern Seaboard and south to Mexico. Large herbivores such as mammoths thrived on these savannahs.

Four times during the Pleistocene, ice advanced engulfing northern regions. The last advance of the two continental ice sheets began 80,000 years ago during the Wisconsin period. But, even this past period was interspersed with warm and cold spells with the last cold spell starting approximately 26,000 years ago and exposing Beringia to its fullest extent as a land bridge.

The Pleistocene was the epoch of megafauna (animals with a body weight of 44 kilograms, 100 pounds, or more), such as mammoths, mastodons, 210-kilogram (500-pound) armadillos, glyptodonts the size of a small car, beavers the size of small bears, camels, horses, giant ground sloths and bison significantly bigger than today’s surviving species. All these animals

became  extinct in North America about 10,000 years ago. 

The woolly mammoth (Mammuthus primigenius) has become an icon of the last Ice Age. Despite its close association with the Ice Age, the thickly-haired mammal evolved from a near hairless species from Africa (even modern elephants have some body hair). The next evolutionary sequence was an ancestral European species, then the Steppe mammoth and finally the woolly mammoth. The Siberian mammal was subjected to extremely harsh climactic and dietary conditions which influenced its adaptation and shift to the new species — the woolly mammoth.

There were actually several species of mammoth endemic to North America — woolly, Jefferson’s mammoth (Mammuthus jeffersonii), the Columbia mammoth (Mammuthus columbi) and a pygmy variety (Mammuthus exilis), remains of which were found on islands off California. An isolated population of pygmy mammoths was still living 6,000 years ago — 4,000 years after the extinction of their larger cousins — on Wrangel Island in Arctic Siberia. They were about 1.8 metres high.

The earliest mammoths originated in southern and eastern Africa about four million years ago and migrated north to  disperse from Western Europe to Siberia and from there to North America.

Mammoth teeth have been found (re Manitoba Historic Resource Branch) in Manitoba near Birds Hill, Dufresne, Rathwell, Rivers, Souris, St. Malo and Bird (near Gillam). Bones have been discovered at Snake Creek (near Erikson), and tusk sections have been recovered near Transcona, Benito, Boissevain and Bird’s Hill. Single mastodon teeth have been unearthed near Blumenort and Moosenose.

Archaeological evidence suggests mammoth and mastodon fossils in Manitoba were deposited during the Watino non-glaciation period 62,000 years ago. The finds in the province bear heavy striations, or scratches, which indicate they were churned up when the ice sheet returned to cover Manitoba.  When the ice sheet began to retreat 14,000 years ago, the province was still inhospitable to mammoths and mastodons until forests and grasslands  reappeared. 

And only along the fringes of glacial Lake Agassiz (the massive lake covered much of southern Manitoba as well as portions of Northwest Ontario, Saskatchewan, North Dakota and Minnesota) would areas be free of water to permit the reintroduction of the two species, although there is no direct evidence to suggest this happened.

If mammoths and mastodons were able to survive along the shores of Lake Agassiz, it is possible Clovis people hunted the large animals. Named after an archaeological site in New Mexico, Clovis people have long been associated with big-game hunting. Evidence of Clovis people in Manitoba has been found on the high ground west of the Manitoba escarpment, but it is scant — only six finely-chipped fluted Clovis spear points have been found in Manitoba.

The Clovis culture has long been reputed to be the first in North America, arriving some 13,000 years ago. But new archaeological evidence suggests humans may have come to North America about 1,300 years earlier via a sea route. Fossilized human excrement recovered from Oregon’s Paisley Caves has been dated to 14,300 years ago, according to a University of Oregon Museum of Natural and Cultural History paper by Dennis Jenkins published in Science magazine.

“If our DNA evidence and radiocarbon dating hold up on additional coprolites (the name for fossilized feces) that are now undergoing testing at multiple labs,” said Jenkins, “then we have broken the Clovis sound barrier ... If you are looking for the first people in North America, you are going to have to step back more than 1,000 years beyond Clovis to find them.”

Whomever came to North America first, evidence is growing that humans drove mammoths to extinction. It has long been argued that the “American Blitzkrieg” or the “Pleistocene overkill hypothesis” was responsible for the extinction of the continent’s megafauna. To make their argument, scientists point out that Clovis projectile points have been found at numerous early human butchering sites of megafauna in Canada and the United States.

The American Blitzkrieg was first proposed by University of Arizona scientist Paul Martin in 1967 to explain why megafauna had survived earlier warm periods but not when the climate warmed 10,000 years ago and humans were already in North America. Martin argued that North America was a hunter’s Eden; large animals had no experience with humans and would not be startled by their approach. The prize for the earliest human hunters was easy access to tonnes of meat that required little effort to obtain. At the time, adult mammoths and mastodons had no natural enemies — lions and sabre-toothed cats inhabiting North America were too small to tackle  the massive beasts. The only possible threat from the big cats was to mammoth and mastodon young, but the youngsters would have been well protected by the herd as is the case when lions threaten  modern elephants calves.

Actually, the only large animals to survive were those species that had a long association with humans such as bison, while home-grown American  species, such as horses and camels, met their demise.

“If a species had populations in Eurasia and North America, it had a better chance of making it through,” palaeontologist John Alroy, University of Southern California at Santa Barbara, told Science News, “even though Eurasia and North America were the two areas where the glaciation was the most intense.” 

In total, some 31 genera of animals became extinct on the continent at the time, and this happened immediately after humans made their first appearance in North America.

“The result shows how much havoc our species can cause, without anyone at the time having the slightest idea about what was going on, much less any intention of causing it,” said Alroy.

What human hunters killed were the large herbivores that had long gestation periods; hence the megafauna under the pressure of human hunting could not replenish their numbers.

A new study by a team headed by Dr. David Nogués of the Museo Nacional Ciencias Naturales in Madrid, has shown the giant creatures were pushed to the brink of extinction by climate change and then forced over the edge by human hunters. Using climate models and fossil distribution, the team led by Nogués-Bravo determined that human hunting delivered the coup de grace.

“The collapse of the climate niche of the mammoth caused a significant drop in their population size, making woolly mammoths more vulnerable to the increasing hunting pressure from human populations,” wrote the Spanish team in the journal PLos Biology.

The team compared the climate between 126,000 years ago to 6,000 years ago — when the last isolated woolly mammoths existed in Arctic Siberia — and the known human population at the time. They determined killing only one mammoth each, every three years would cause the extinction of the already climate-stressed animals.

When the last mammoths lived, their habitat had shrunk to just 10 per cent of the extent that had been available to them  42,000 years ago when glaciers were covering much of the northern hemisphere. Eight thousand to 6,000 years ago, the climate had warmed enough for humans to move into the tundra habitat where mammoths still existed.

The researchers came to their conclusions after determining that mammoths had not gone extinct 126,000 years ago when there was an interglacial period and the northern climate in North Eurasia was relatively warm — the missing ingredient 126,000 years ago was humans.