May 30, 2014
Dogs May Have Helped Early Man Hunt Mammoths To Extinction
Brett Smith for redOrbit.com - Your Universe Online
Scientists have long-suspected that our ancestors were at least partially to blame for the extinction of the mammoth and a new research review from a Penn State anthropologist has revealed that ancient humans may have had an accomplice – domesticated dogs.The new study, published in the journal Quaternary International, is based on past examinations of European archeological sites with large numbers of mammoth remains. Study author Pat Shipman not only suggested that humans and dogs worked together to hunt mammoths – she also provided a way to test her theory.
"One of the greatest puzzles about these sites is how such large numbers of mammoths could have been killed with the weapons available during that time," said Shipman, a professor of anthropology at Penn State, in a recent statement.
Many previous analyses of the mammoths at these locations discovered similarities with those of modern elephants slaughtered by hunting or natural disasters. However, the new evaluation of the previous scientific studies discovered that they didn't have the statistical evaluations essential for concluding how these animals were slaughtered.
According to Shipman, "Few of the mortality patterns from these mammoth deaths matched either those from natural deaths among modern elephants killed by droughts or by culling operations with modern weapons that kill entire family herds of modern elephants at once."
Based on this disparity, the Penn State researcher said another technique for killing large pachyderms must have been used to take down the mammoth herds. During the course of her review, Shipman found a few of the large carnivores at these locations were early domesticated dogs, not wolves as had been suspected. Based on this evidence, Shipman used data on how humans hunt with dogs to formulate several testable models for these mammoth locations.
"Dogs help hunters find prey faster and more often, and dogs also can surround a large animal and hold it in place by growling and charging while hunters move in. Both of these effects would increase hunting success," Shipman said. "Furthermore, large dogs like those identified by (a previous study) either can help carry the prey home or, by guarding the carcass from other carnivores, can make it possible for the hunters to camp at the kill sites."
Shipman said she could confirm her models using other analyses and noted, "If hunters working with dogs catch more prey, have a higher intake of protein and fat, and have a lower expenditure of energy, their reproductive rate is likely to rise."
The study also pointed out evidence of other large predators around the mammoth kill sites, such as wolves and foxes.
"Both dogs and wolves are very alert to the presence of other related carnivores -- the canids -- and they defend their territories and food fiercely," Shipman explained. "If humans were working and living with domesticated dogs or even semi-domesticated wolves at these archaeological sites, we would expect to find the new focus on killing the wild wolves that we see there."
Two studies in the review seemed to back Shipman’s hypothesis. One study found the animals identified as dogs had different diets than those identified as wolves – possibly a sign of domestication. Another study based on mitochondrial DNA found that animals identified as dogs have a genetic makeup different from other canids.
Shipman concluded that her hypothesis will be confirmed "if more of these distinctive doglike canids are found at large, long-term sites with unusually high numbers of dead mammoths and wolves; if the canids are consistently large, strong individuals; and if their diets differ from those of wolves," Shipman said. "Dogs may indeed be man's best friend."
Image 2 (below): The photo shows part of the very-high-density concentration of mammoth bones at the Krakow-Spadzista Street archaeological site. Credit: Piotr Wojtal.