As the overview article showed, the heart of Anthony’s book is combining linguistic reconstruction with archaeological evidence. Let’s start with the most memorable episode in that search for evidence.
A casual question to a vet school
In the summer of 1985 I went with my wife Dorcas Brown, a fellow archaeologist, to the Veterinary School at the University of Pennsylvania to ask a veterinary surgeon a few questions.
The question was simple: does a bit — the metal piece a horse holds in its mouth — leave marks on its teeth? If it does, then examining ancient horse teeth might reveal when people first put a bit in a horse’s mouth and rode it.
The first surgeon they spoke to said no, it shouldn’t leave a mark. But when they asked trainers who worked with horses every day at the university’s riding center, the answer was completely different. Horses, it turned out, chew on their bits constantly.
What an X-ray revealed about tooth wear
Anthony and his colleagues then worked with the Canadian veterinary researcher Hillary Clayton, who obtained X-ray footage of horses holding a bit in their mouths. This footage showed, for the first time, precisely where and how the bit kept pressing against the teeth. A specific tooth in the lower jaw — the second premolar — turned out to develop a regular pattern of wear.
This established a method: examine the bones of an ancient horse — specifically, that one tooth — and you can determine whether it was ever bitted.
A second clue — a strange asymmetry in horse DNA
The book introduces another fascinating clue. Genetic studies of modern domestic horses show that the line passed from mother to daughter (mitochondrial DNA) is remarkably diverse — traceable to at least 77 separate wild mares. But the line passed from father to son (the Y chromosome) is, by contrast, strikingly uniform, traceable to only a handful of wild stallions.
In other words, horse domestication seems to have been a lopsided process: many wild mares were taken in, while only a very few wild stallions were ever chosen. This lines up neatly with the social behavior of wild horse herds, where a single stallion controls a territory and a harem of mares — a persuasive piece of corroborating evidence.
From one question, a method is born
What makes this story compelling is that it starts from a simple hunch — maybe examining a horse’s teeth would tell us something. The first expert’s answer was “we don’t know.” But by asking people who actually work with horses, and then verifying it with an X-ray, solid evidence finally emerged. The next article looks at a second clue — the word for “wheel” — and how it, too, became a tool for dating a dead language.
Summary
| Point | Detail |
|---|---|
| Starting point | A simple question: does a bit leave a mark on a horse’s teeth? |
| Verification | Veterinary X-ray footage pinpointed exactly where the bit wears the tooth |
| Genetic clue | Domestic horses’ maternal line is diverse, paternal line is uniform — suggesting a lopsided domestication process |
| Consequence | Examining ancient horse teeth became a way to date the origin of riding |
In a nutshell — Anthony traced the origin of riding, an act that left no written trace, through evidence carved into the horse’s own teeth.