Just as Secretariat found the norms of the breed unsuited to his excellent traits, other stallions with championship qualities have found themselves needing mates with different traits.
One of the reasons for some stallions needing mares with traits that are difficult to find is that the mares most likely to possess them are from the same lines as the stallion. The noted vet Dr. Bishop suggested that the thing to do with Secretariat was to mate him with his own daughters. This was never done, in part because we think of such matings from the human perspective as incestuous. Also, unless the mares were chosen for good qualities and lack of faults, the results would tend not to be very useful.
Another tack, in Secretariat’s case, would have been to use mares by Nasrullah, Bold Ruler, Princequillo, or one of the better Bold Ruler or Nasrullah sons. These horses tended to gravitate toward the stride type, and doing something like, while eccentric, would have created a sort of miniature “breed center” around Secretariat and might possibly have worked.
When considering the concept of the “center of the breed” in biomechanical terms, it sounds as if the norms of the breed are a static center, but there does appear to be evidence that the norms can drift, or perhaps even realign to form a somewhat different and more specialized center of the breed.
Particularly with regard to the preferred stock of the commercial market of the last 20 years, the change has been toward both a larger horse and one with a bigger hip (both wider and longer) and longer hind cannon. These are the traits especially associated with Native Dancer, Raise a Native, Fappiano, and Dr. Fager.
These are horses with extraordinary speed, but they were not purely sprinters and did not get their speed simply by muscle mass and rapid acceleration.
And if we think about Fappiano, in particular, most would agree that the outstanding sire son of Mr. Prospector combined some traits that were fairly atypical of Mr. Prospector, but that were more typical of Native Dancer and Raise a Native, with the best qualities of Dr. Fager.
This recombination of traits is the essence of the breed-shaping stallion who literally can remake the breed, or a portion of it, in his own image. For many outstanding racehorses, being atypical has been the death of their prospects of consistent success at stud. But this has not been the case for the power type of horse with the Native Dancer hip and the big frame of a Dr. Fager or Fappiano.
On the contrary, they have prospered because there are enough of this type out there to help one another as mates. As the number of high-quality horses has increased over the past 30 years or so, the opportunity for stallions to find suitable mates, even by chance, has likewise increased.
And breeders have every reason to use this type of mare and stallion in their matings because this tall Quarter Horse type has become the preferred commercial prospect, both at the yearling sales and especially at the auctions of 2-year-olds in training.
And as a result of this growth in popularity, some of the types or “populations” of horses that were not common enough to dominate the breed in earlier decades are now coming to have a larger influence on the breed.
The looming struggle for influence among different types of racehorses will be focused on the relative pressures in breeding and racing to retain the typey, muscular, medium-sized horse typical of Type I or to replace that with the larger, rangier, power-centered horse.
Unbridled’s Song, grandson of Fappiano through the outstanding sire Unbridled, is the prototype of the big power horse, and there could hardly be a more popular sire and physical profile, especially for the commercial breeder and buyer. On the other hand, Distorted Humor is the heir to Danzig, Mr. Prospector, and others of the Type I center.