Dale Guthrie of the University of Alaska claims trees overtook the mastadon habitat and that is why they died off. Alot of the plains mega-fauna died off 12,000 years ago. But this didn't happen! Plenty of megafauna survived! Buffaloes and grizzlies, just for example. Imagining how this works requires thinking like a farmer.
for National Geographic News
May 10, 2006
The plot thickens.
New findings suggest that an ongoing, epic whodunit may actually be a whatdunit. That is, climate change, not humans, may be what killed off Ice Age mammoths, horses, and other large animals in North America.
Dale Guthrie, a researcher at the University of Alaska in Fairbanks, has spent some 20 years examining more than 600 bones of large mammals from Alaska and the Yukon Territory.
His analysis points toward climate as the culprit.
Guthrie's data, published in tomorrow's issue of the journal Nature, shows that increases in moisture and warmer temperatures 13,500 to 11,500 years ago allowed for edible plants to migrate north.
But then the milder climate backfired on the big mammals. It paved the way for trees, which eventually outshaded and outcompeted the low-lying plants the animals depended on, Guthrie says.
There are many problems with his hypothosis. One is, anyone who has any experience with horses and cattle (forget giant elephantine animals!) is, NO trees can grow unless you fence them away from the large grazing mammals! Period. Even if pine trees can grow, they get smooshed. I had one of America's biggest ox teams. Each boy weighed in at over a ton. Where they walked, when the ground was damp, they left deep imprints. Imagine now a herd of 100,000 Chip and Dale ton+ oxen stampeding across a flat plain!
Worse, these giant cattle I owned came from Switzerland which is mountainous. So they not only ranged on the plains, they lived in high mountains. And they could graze on nearly anything.
Trees were candybars to them!
Chip and Dale would take their sweeping horns which spanned four feet and hook them on tree branches and pull the branch down and eat them. They would snap off branches. They would rub against trees including pine trees and knock them down. When shedding fur, Sparky, the Ice Age Horse from Switzerland and Chip and Dale would rub the old fur off using pine trees. The stags in the forest would come into the fields to rub the fur off their growing horns in early fall. I have actually seen them doing this.
The trees take a lot of damage. No great plain has many trees precisely because massive herds of tree killing animals roam about seeking trees to destroy! Grazing herds=savannah grasses. Grasses and grazing animals evolved in tandem. There is NO FRICKING WAY that trees can "push out" any grazing animal! One silly Sparky and eliminate all the trees for 100 square miles over the course of a year if he isn't penned into his pasture which he spends all day trying to figure out, how to get out.
So this scientist, being not a farmer, thinks that tiny saplings can destroy a mammoth's home turf. Gah.
What happened back then and why did it not affect the vast herds of elephants and lions gazelles and whatever in Africa? Well, humans figured out how to hunt not only with spears but with DOGS. Sparky broke out of his pasture today. So my dogs got to work, barking at him. Wooo woo woo. They snapped at his hocks and he kicked them. Woo woo woo. Out comes the human. "Sparky, get back into your pasture," she yells. Sparky snorts and goes into his pasture.
Now a new study of the fossil record fuels the debate about the cause of the creatures' fate.
In North America two major events occurred at about the same time as the megafaunal extinctions: The planet cooled, and early humans arrived from Asia to populate the continent.
For decades scientists have debated which of these factors was responsible for widespread megafaunal extinctions.
Was the climate change simply too much for the animals to withstand? Or did the ancient mammals succumb to human hunting pressure?
Many experts suggest a combination of these factors and perhaps others, such as disease.
"It's hard to see this as one of those things where a single piece of evidence will make it obvious what happened," said Scott Wing, a paleobiologist at the Smithsonian Institution's National Museum of Natural History.
Now, if I wanted to eat Sparky, I would have chucked my spear into him and he would have fed the dogs who know deep in their brains Sparky=food. This is why they bark at strangers, too. Strangers=food.
A survey of British skulls from the early part of the New Stone Age, or Neolithic, shows societies then were more violent than was supposed.
Early Neolithic Britons had a one in 20 chance of suffering a skull fracture at the hands of someone else and a one in 50 chance of dying from their injuries.
Details were presented at a meeting of the Society for American Archaeology and reported in New Scientist magazine.
Blunt instruments such as clubs were responsible for most of the trauma.
Early on, one of the biggest breed of dogs, the English Mastiff, evolved on that small island. I once had a magnificent English Mastiff, Cleo. This lovely 250 lb dog was fiercely loyal to me and if anyone came wandering onto our lands, she would came stampeding out of nowhere to assault them. Her bark was very loud and she was so scary, she scared bears. One day a black bear came to raid the honey hives in the dark. Sparky hates bears and he ran home to neigh at us.
Cleo ran outside and bellowed at the bear. She then took off into the woods chasing the bear who ran faster and faster, they both disappeared over the ridge and we went hiking, calling back the dog. She came home, panting, the bear never came back.
Once, some people who were rather unfriendly decided to pay me a warning visit. They had criminal records and were pissed that I talked to the police about their activities. Wooo woo woo went Cleo as she pelted down the mountain as they drove up, spittle flying from her gaping mouth. She attacked their truck and they went into reverse, yelling. The other dogs ran up and chased them down the mountain and then down Greenhollow Rd. They never came back, either. (I was also there with a great defense tool in my hands, heh).
The deadly combo of dog and man is what destroyed many fauna. We ate everything in our path and when the larger game was killed, trees could finally grow again.
Scientists think the domestication of dogs happened first in the great plains of Eurasia and spread rapidly. This is simple to explain. When humans without dogs met ones with dogs the dog owners won. Ancient chroniclers point this out. Egypt, when becoming an empire, used dogs in battle, for example. The city builders in the Euphrates valley fought with massive mastiff style dogs. They made many carvings and paintings showing how these dogs fought. One victory parade in Egypt had 500 fighting mastiffs marching in it.
There are carvings showing kings in Eurasia using early chariots to hunt lions using mastiffs. In every carving or painting, the mastiffs are pulling down the lions while the spear and bow hunters pepper the lions with their weapons.
The hunting humans in the New World wiped out mastodons who propably had few predators and were therefore defenseless when meeting a serious predator conglamorate. But the giant bears which we now call "grizzlies" could fight off the dogs and humans sufficiently to keep alive. And the giant oxen which we call "buffalo", thanks to their eternal battles with the wolves, could evade humans hunting them. So why did horses disappear?
Back to Sparky: for some reason, horses like to fool around with humans. Don't ask me why. But they can't help themselves. Like zebras in Africa, they probably moved at the perimeter of vast cattle herds. This meant, the dogs and humans could pick them off even as the more dangerous cows ran off in a massive stampede. I suppose that one day, in Eurasia, instead of eating the horse, someone captured some and used them to herd the cattle. And thus, the first cowboy, some neolithic genius, domesticated two important large grazing animals.
Note that reindeer in Lapland had the same fate: instead of being eaten by the humans and dogs, they flourished down to this day, being herded by the humans and dogs and being used for transport as well as harvested carefully.
The same goes for Africa: cows and goats and other useful animals are herded hither and yon by humans and dogs. They flourish, too. Indeed, this human/animal interface is what characterizes most environments across the planet.
In Australia, only the large kangaroo survived the invasion of the humans and their dingo dogs. This is because the kangaroos move very fast, jump very high like gazelles and can fight fiercely when cornered and they don't interfer with the human's habitat like cave bears, for example.
Do note that gazelles and mountain sheep and all such animals did NOT go extinct when humans invaded. This is because they are either very swift or lived in steep mountains. What destroys their environments is desertfication. This is the real developing danger. Deserts can't hold many niches for large animals.