As one of the earliest domesticated animals, dogs evolved from wolves into what we now know as extremely diverse domesticated animals that range from almost horse-sized Great Danes to little teacup-sized pets. Some breeds evolved into mostly indoor family members and furry loved ones (especially today), while others were given jobs and bred for such. Herding, one of the world’s oldest occupations, occurred not only with the animals meant for food at the time but also with our canid friends.
Claims have been made over time that dogs practically domesticated themselves. One central theory in this is the availability of human food and supplies were also available to wolves. It is accepted that gray wolves and dogs split from an extinct wolf species. Many studies have been conducted, and almost all of them conclude a different time frame based on the information or samples analyzed (with or without any geographic bias). Arguably, the current time frame rests between 15,000 and 40,000 years ago until further evidence is found.
It's a new study, however, that suggests ancient, domesticated dogs may have doubled in size to protect herds more efficiently. This type of evolution doesn't just happen over a few years or even decades, but hundreds of years. They protected herds from bears, saber-toothed cats, and even their ancestor, the gray wolf. Since domestication, dogs have earned a diverse role in the human environment.
Another study shows that with increasing social complexities and political systems, so did their agricultural practices during the Bronze and Iron ages. Dog remains found at archaeological sites off the coast of Croatia have allowed scientists to understand the changes these animals underwent through their human connections.
Among pastoral and agropastoral societies, dogs have consistently exhibited immense utility regarding herding and protecting livestock, with some characteristically bred for this purpose. Dogs have consistently served two distinct roles: guardians of flocks and predator deterrents and herders following human commands herding across landscapes. Exposures of the dogs to various livestock at a specific age range made it critical for developing their interaction with sheep for herding. This is the period of brain development responsible for social bonding within canines.
Previous measurements of canine variability have primarily relied upon shoulder height. However, this study focused on the use of body mass since shoulder height can only be determined if remains are complete enough. On average, herding dogs weigh between 10 to 20 kilograms, and guarding dogs between 30 to 55 kilograms.
The wolf size and population at the time of domestication may correlate to the dogs' sizes as purely an environmental adaptation to local changes and transhumance. Transhumance is the livestock migration pattern of lower altitudes in colder temperatures and mountain pastures during the summer wherein humans follow their herds.
Dogs have frequently shown changes that also demonstrate the differences in human treatment. Many of the large breeds utilized for guarding subsequently showed variability in sizes, most likely due to pressures from transhumance and pastoralism.
Most archaeological data today suggest size differences from the Balkans to the Mediterranean and into Europe potentially rooted in differences in the above noted agricultural practices and show significant increases in dog sizes between the Neolithic and Bronze ages.
For an animal so strongly rooted in human history and culture, the argument over initial domestication remains to be settled. One day, former competitors could eventually turn collaborative in the scientific community to better understand this human-canid connection that we cherish today.