Recently, we casually read through the FCI standard for the Transmontano Mastiff, or, as it is listed in that registry, the Cão de Gado Transmontano. In the Brief Historical Summary section, we read: “In remote times, this dog settled in the Portuguese highlands, namely in Trás-os-Montes. In this mountainous area, characterized by steep pastures of difficult road access, the breed adjusted to the region’s conditions and sheep and goat flocks that, traditionally, graze in these areas, evolving until its morphological traits were defined, in perfect symbiosis with the environment and with the work demanded.”

We’ve bolded the sentence that got us to wondering what it even means. Of course, we all understand it conveys the fact that over time, the breed changed to suit its environment, but if the devil is in the details, as they say, then so is getting into the nitty-gritty of the statement.  Did the Cão de Gado Transmontano magically evolve on its own? How much of a role did human shepherds play in this?

We think it developed the way most true landrace livestock guardians have, which is to say that the breed was a product of co-selection: Nature eliminated the weak, and shepherds chose the best of what remained.  For a more vivid illustration, we liken the process to sifting dirt through a sieve: Each “sift” removes unwanted particles until all that remains are the wanted pieces.

The first “filter” in this breed was natural pressure – or selection-by-environment.

• This was a slow maturing breed, a clear advantage in a livestock guardian.  Why? The dogs gained time to develop judgment, flock sense, and territorial awareness under the guidance of older dogs before facing serious threats on its own. Growing gradually supports stronger joints and steadier metabolic development in harsh, resource-limited mountain environments. In rugged wolf country, patience in body and mind was a survival strategy because the dogs wasn’t yet big enough to attract a fight;
• Large, rugged mountains required exceptional stamina in a dog that lived in them. This called for a long stride and an efficient trot to effectively patrol vast grazing areas every day;
• Unforgiving cold winters and hot summers necessitated a dense, weather-resistant coat in a slow maturing dog
• A large body would conserve heat, while a slow metabolism was better suited for dry summers; In the presence of wolf predation pressure, a large size was also a physical deterrence, to say nothing of the “head games” that Portugal’s largest breed would present to a wolf;
• Sturdy bones and great feet favored the dog who had to work in rocky, uneven ground. It gave him durability and reduced injury in rough terrain; Remember, now, that these were dogs that worked largely on their own, and unsound dogs led to frequent injuries that wouldn’t always be tended by a shepherd.  A sparse human presence required an independent dog able to make its own decision without constant direction;
• Because the Cão de Gado Transmontano watched over sheep and goats, the breed needed a balanced temperament that could guard flighty sheep as well as pushy, bold goats without  overreacting to either.

Over time, the dogs became “morphologically fixed,” which is to say that their physical and working traits became fixed, consistent, stable, and recognizable as a distinct breed, and as an aside, that’s what transformed the breed from a landrace to a distinct breed accepted by the FCI.

Photo taken in Portugal by EyeEm Mobile GmbH of a Cão de Gado Transmontano at work