Why Secretariat's 1973 Record Still Stands: The Genetic Paradox of the Thoroughbred
The Ultimate Horse
In 1973, Secretariat won the Belmont Stakes by 31 lengths, a record that remains unbroken despite billions spent on breeding. This article explores the evolutionary history of horses, from tiny forest dwellers to modern breeds, and reveals a paradox: centuries of selective breeding for speed and docility have narrowed genetic diversity, potentially limiting further improvement and robustness. Drawing on ancient DNA and archaeological evidence, it traces the origins of domestic horses to the Botai culture and the later DOM2 lineage, and examines how human preferences shaped everything from coat color to gaits.
This is the paradox of the thoroughbred: breeders have spent centuries trying to create a faster horse, but in doing so, they may have bred away the very genetic diversity that would allow the horse to keep improving, or even to remain robust.
- jaegrqualm
Genetic diversity is a very interesting topic that’s well worth exploring, but it seems to me that Occam’s razor requires us to consider the possibility they just had a really good, well timed dosage of performance enhancing drugs for Secretariat back in the day.
- abeppu
I think it's surprising that the article predicts the impacts of gene editing to be relatively small.
> Even so, the prospects for exceeding current records through gene editing are slim. Today’s racehorses are already tightly optimized for speed, balancing strength against the cost of carrying additional muscle mass. Adding more muscle is relatively low-hanging fruit, and if this were the key to unlocking greater speed, selective breeding would likely already have brought it about.
It's a whole new tool in the toolbox, and can introduce mutations that didn't first arise by chance in order to be then spread with selective breeding.
- gadders
I don't know why the article goes on so much about Secretariat. Flat races are horse races on easy mode. Steeplechases are proper horse racing