Stunning Evidence Suggests Dogs Lived During the Ice Age
by Dr. Karen Becker
While it’s known that dogs descended from wolves to become humans’ best friends, when — and exactly how — this occurred remains a great mystery and highly debated topic. Genetic data confirms that dogs are descendants of Eurasion grey wolves, and early humans and wolves were known to share resources and territories dating back hundreds of thousands of years.
Skeletal changes suggestive of dog domestication have been discovered dating back to the Aurignacian period some 43,000 to 26,000 years ago, and by 16,000 to 12,000 BP (before present), domestic dogs were known to exist in Western Europe, Asia and North America, with purposeful burials of dogs also occurring at this time.
Still, researchers wrote in the Journal of Archaeological Science, “The beginning of this domestication process … remains a point of debate, with purported originations ranging from 15,000 to over 40,000 BP.”1
Understanding when this process occurred isn’t only a matter of satisfying curiosity — animal domestication signals a shift in humans’ relationship with nature and changes in human cognition and behavior. Uncovering when this first occurred will help researchers to also understand early Homo sapiens.
Researchers from the University of Arkansas may be one step closer to figuring out the mystery, after an analysis of Paleolithic-era teeth showed evidence of two groups of canids — “one dog-like and the other wolf-like”2 — existing at that time.
Dental Differences Suggest Dogs Emerged During Ice Age
The study involved fossils from a 28,500-year-old site known as Predmostí in the Czech Republic. A dental microwear texture analysis was performed on the ancient teeth, which identified distinctive microwear patterns on the differing canids. The dog-like canids, which the researchers called “protodogs,” had larger wear scars that suggest they ate more hard, brittle foods such as bones.
The wolf-like canids, on the other hand, had smaller scars, which could indicate they ate more flesh-based food, such as mammoth flesh. Peter Ungar, distinguished professor of anthropology at the University of Arkansas, explained in a news release:
“Our primary goal was to test whether these two morphotypes expressed notable differences in behavior, based on wear patterns … Dental microwear is a behavioral signal that can appear generations before morphological changes are established in a population, and it shows great promise in using the archaeological record to distinguish protodogs from wolves.”3
While the fossil site is believed to contain fossils from wolf-like and dog-like canids, the dental differences provide supporting evidence that the animals had distinct diets. The wolf-like canids likely feasted on flesh caught by hunting while the dog-like canids may have eaten more bones and other food scraps that came from a human settlement.
“Dental microwear is a behavioral signal that may appear generations before morphological changes are established in a population. It shows promise for distinguishing protodogs from wolves in the Pleistocene and domesticated dogs from wolves elsewhere in the archaeological record,” researchers wrote in the Journal of Archaeological Science.4
Paleolithic Dog Skulls Revealed
In 2012, researchers analyzing skull material from the same fossil site in the Czech Republic came to the conclusion that both dog and wolf skulls exist there.5
Three complete skulls were identified as belonging to ancient dogs, which were characterized by short skulls and snouts and wide palates and braincases compared to wolves. The ancient dogs had skulls shaped similar to that of a modern-day Siberian husky, but larger in size and heavier.
Three other skulls could not be identified, with researchers suggesting they could be from hybrids or captive wolves. Further, they noted that the skull and canine remains were modified by humans, which suggests a relationship existed between humans and large canids at the time.
For instance, one of the dogs had a mammoth bone in his mouth, which was believed to have been placed there after death. “The mammoth bone in the dog’s mouth could signify “that the dog was ‘fed’ to accompany the soul of the dead (animal) on its journey,” according to lead study author Mietje Germonpré.
Their conclusions, however, particularly the supposed presence of two distinct canid populations at the fossil site, were met with debate. The featured study, with its detailed dental analysis, adds further support that ancient dogs may have existed alongside wolves during the Ice Age. The researchers even made suggestions as to their respective diets:
“Isotope analysis suggests wolves and humans focused on mammoth, while dogs and lions focused on reindeer and other prey. Protodogs fed scraps would have been better able to break and consume the bones of reindeer and smaller prey compared to mammoths, and this may help explain the signal.
Alternatively, protodogs may have opportunistically scavenged off felid kills, as felids typically leave more flesh as well as marrow containing bones than do canids or hyaenids.”6
Still, even with this combined evidence, it’s possible that the two canid groups were actually different wolf populations that had developed different dietary behaviors due to increased competition or environmental changes. Further research will be necessary before the ongoing debate will be ended revealing when dogs were first domesticated.
As for why domestication occurred, it’s believed that wolves may have become integrated into human society because canids fulfilled important functions in the daily life of Paleolithic people, helping them with hunting and other work, offering protection and, just as they do today, providing a source of faithful companionship.